Efavirenz

Efavirenz is used along with other medications to treat human immunodeficiency virus (HIV) infection. Efavirenz is in a class of medications called non-nucleoside reverse transcriptase inhibitors (NNRTIs). It works by decreasing the amount of HIV in the blood. Although efavirenz does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting (spreading) the HIV virus to other people.

Efavirenz comes as a capsule and as a tablet to take by mouth. It is usually taken once a day with plenty of water on an empty stomach (at least 1 hour before or 2 hours after a meal). Take efavirenz at around the same time every day. Taking efavirenz at bedtime may make certain side effects less bothersome. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take efavirenz exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets and capsules whole; do not split, chew, or crush them.

If you are not able to swallow the medication whole, you can still take efavirenz by mixing the contents of the capsule with soft food and eating. To prepare each dose, open the capsule and sprinkle the contents onto 1-2 teaspoons of soft food in a small container. You can use soft foods such as applesauce, grape jelly, or yogurt. While sprinkling, be careful not to spill the contents of the capsule, or spread it in the air. Mix the medicine with the soft food. The mixture should look grainy but should not be lumpy. You must eat the medicine and soft food mixture within 30 minutes of mixing. When you are finished, add another 2 teaspoons of soft food to the empty container, stir, and eat to be sure that you have received the full dose of medication. Do not eat for the next 2 hours.

If efavirenz is being given to a baby who can not yet eat solid foods, the contents of the capsule can be mixed with 2 teaspoons of room temperature infant formula in a small container. While emptying the capsule, be careful not to spill the contents, or spread it in the air. The mixture should look grainy but should not be lumpy. The mixture should be syringe fed to the baby within 30 minutes of mixing. When finished, add an additional 2 teaspoons of infant formula to the empty container, stir, and syringe feed to the baby to be sure that you have given the full dose of medication. Do not give the medication to the baby in a bottle. Do not feed the baby for the next 2 hours.

Efavirenz controls HIV infection, but does not cure it. Continue to take efavirenz even if you feel well. Do not stop taking efavirenz without talking to your doctor. When your supply of efavirenz starts to run low, get more from your doctor or pharmacist. If you miss doses or stop taking efavirenz, your condition may become more difficult to treat.

Efavirenz is also used with other medications to help prevent infection in healthcare workers or other people who were accidentally exposed to HIV. Talk to your doctor about the possible risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking efavirenz,

• tell your doctor and pharmacist if you are allergic to efavirenz any other medications, or if you are allergic to any of the ingredients in efavirenz capsules or tablets. Ask your doctor or pharmacist for a list of the ingredients.

• you should know that efavirenz is also available in combination with another medication with the brand name of Atripla. Tell your doctor if you are taking this medication to be sure you do not receive the same medication twice.

• tell your doctor if you are taking elbasvir and grazoprevir (Zepatier). Your doctor will probably tell you not to take efavirenz if you are taking this medication.

• tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: antidepressants, artemether and lumefantrine (Coartem), atazanavir (Reyataz), atorvastatin (Lipitor, in Caduet), atovaquone and proguanil, bupropion (Wellbutrin, Zyban, others, in Contrave), carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Teril), clarithromycin (Biaxin, in Prevpac), cyclosporine (Gengraf, Neoral, Sandimmune), delavirdine (Rescriptor), diltiazem (Cardizem CD, Cartia XT, Diltzac, Taztia XT), ethinyl estradiol and norgestimate (Estarylla, Ortho-Tri-Cyclen, Sprintec, others), etravirine (Intelence), etonogestrel (Implanon, Nexplanon, Nuvaring), felodipine, fosamprenavir (Lexiva), itraconazole (Sporanox), indinavir (Crixivan), levonorgestrel (Mirena, Plan B one step, Skyla, in Climera Pro, Seasonale, others), lopinavir (in Kaletra), maraviroc (Selzentry), medications for anxiety, medications for mental illness, medications for seizures, methadone (Dolophine, Methadose), nevirapine (Viramune), nicardipine (Cardene), nifedipine (Adalat, Afeditab, Procardia XL), norelgestromin (in Xulane), phenobarbital, phenytoin (Dilantin, Phenytek), posaconazole (Noxafil), pravastatin (Pravachol), rifabutin (Mycobutin), rifampin (Rifadin, Rimactane, in Rifamate, Rifater), rilpivirine (Edurant, in Complera, Odefsey), ritonavir (Norvir, in Kaletra, Technivie, Viekira), saquinavir (Invirase), sedatives, sertraline (Zoloft), simeprevir (Olysio), simvastatin (Zocor, in Vytorin), sirolimus (Rapamune), sleeping pills, tacrolimus (Envarsus XR, Prograf), tranquilizers, verapamil (Calan, Covera, Verelan, in Tarka), voriconazole (Vfend), and warfarin (Coumadin, Jantoven). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with efavirenz, or may increase the risk that you will develop an irregular heartbeat, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.

• tell your doctor what herbal products you are taking, especially St. John's wort.

• tell your doctor if you have or have ever had prolonged QT interval (a rare heart problem that may cause fainting or irregular heartbeat), irregular heartbeat, other heart problems, have ever drunk large amounts of alcohol, used street drugs, or over-used prescription medications. Also tell your doctor if you have or have ever had depression or other mental illness, seizures, hepatitis (a viral infection of the liver) or any other liver disease disease.

• tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant during your treatment and for 12 weeks after your final dose. If you can become pregnant, you will have to have a negative pregnancy test before you begin taking this medication and use effective birth control during your treatment. Efavirenz may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, implants, or injections), so you should not use these as your only method of birth control during your treatment. You must use a barrier method of birth control (device that blocks sperm from entering the uterus such as a condom or a diaphragm) along with any other method of birth control you have chosen. Ask your doctor to help you choose a method of birth control that will work for you. If you become pregnant while taking efavirenz, call your doctor.

• you should not breast-feed if you are infected with HIV or are taking efavirenz.

• you should know that efavirenz may make you drowsy, dizzy, or unable to concentrate. Do not drive a car or operate machinery until you know how this medication affects you.

• ask your doctor about the safe use of alcoholic beverages while you are taking efavirenz. Alcohol can make the side effects from efavirenz worse.

• you should know that while you are taking medications to treat HIV infection, your immune system may get stronger and begin to fight other infections that were already in your body or cause other conditions to occur. This may cause you to develop symptoms of those infections or conditions. If you have new or worsening symptoms during your treatment with efavirenz, be sure to tell your doctor.

• you should know that your body fat may increase or move to different areas of your body such as your breasts and upper back, neck (''buffalo hump''), and around your stomach. You may notice a loss of body fat from your face, legs, and arms.

• you should know that efavirenz may cause changes in your thoughts, behavior, or mental health. Call your doctor immediately if you develop any of the following symptoms while you are taking efavirenz: depression, thinking about killing yourself or planning or trying to do so, angry or aggressive behavior, hallucinations (seeing things or hearing voices that do not exist), loss of touch with reality, or other strange thoughts. Be sure your family knows which symptoms may be serious so that they can call your doctor if you are unable to seek treatment on your own.

• you should know that efavirenz may cause potentially serious nervous system problems, including encephalopathy (a serious and potentially fatal disorder of the brain) months or years after you first take efavirenz. Although nervous system problems may begin after you have taken efavirenz for some time, it is important for you and your doctor to realize that they may be caused by efavirenz. Call your doctor right away if you experience problems with balance or coordination, confusion, memory problems, and other difficulties caused by abnormal brain function, at any time during your treatment with efavirenz. Your doctor may tell you to stop taking efavirenz.

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

• Efavirenz may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea

  • vomiting

  • stomach pain

  • diarrhea

  • indigestion

  • headache

  • confusion

  • forgetfulness

  • feeling anxious, nervous, or agitated

  • abnormally happy mood

  • difficulty falling asleep or staying asleep

  • unusual dreams

  • pain

• Some side effects can be serious. If you experience any of the following symptoms or those mentioned in the SPECIAL PRECAUTIONS section, call your doctor immediately:

  • fever

  • rash

  • itching

  • peeling, blistering, or shedding skin

  • mouth sores

  • pink eye

  • swelling of your face

  • fainting

  • irregular heartbeat

  • extreme tiredness

  • lack of energy

  • loss of appetite

  • pain in the upper right part of the stomach

  • unusual bleeding or bruising

  • yellowing of the skin or eyes

  • flu-like symptoms

  • seizures

• Efavirenz may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

• If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

• movements of your body that you cannot control

• dizziness

• headache

• difficulty concentrating

• nervousness

• confusion

• forgetfulness

• difficulty falling asleep or staying asleep

• unusual dreams

• drowsiness

• hallucinations (seeing things or hearing voices that do not exist)

• abnormally happy mood

• strange thoughts

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to efavirenz.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking efavirenz.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

• Atripla^® (containing Efavirenz, Emtricitabine, Tenofovir)

Drug	Interaction
Moxifloxacin	Moxifloxacin The risk or severity of QTc prolongation can be increased when Moxifloxacin is combined with Efavirenz.
Repaglinide	Repaglinide The metabolism of Repaglinide can be decreased when combined with Efavirenz.
Montelukast	Montelukast The metabolism of Montelukast can be decreased when combined with Efavirenz.
Insulin Glargine (rDNA origin) Injection	Insulin Glargine (rDNA origin) Injection The metabolism of Efavirenz can be increased when combined with Insulin glargine.
Leflunomide	Leflunomide The serum concentration of Leflunomide can be decreased when it is combined with Efavirenz.
Nevirapine	Nevirapine The metabolism of Nevirapine can be increased when combined with Efavirenz.
Atorvastatin	Atorvastatin The serum concentration of Atorvastatin can be decreased when it is combined with Efavirenz.
Dolasetron	Dolasetron The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Dolasetron.
Aminophylline	Aminophylline The metabolism of Aminophylline can be increased when combined with Efavirenz.
Anagrelide	Anagrelide The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Anagrelide.
Candesartan	Candesartan The metabolism of Candesartan can be decreased when combined with Efavirenz.
Cilostazol	Cilostazol The serum concentration of Cilostazol can be increased when it is combined with Efavirenz.
Clopidogrel	Clopidogrel The serum concentration of the active metabolites of Clopidogrel can be reduced when Clopidogrel is used in combination with Efavirenz resulting in a loss in efficacy.
Diphenoxylate	Diphenoxylate The risk or severity of adverse effects can be increased when Efavirenz is combined with Diphenoxylate.
Erythromycin and Sulfisoxazole	Erythromycin and Sulfisoxazole The metabolism of Erythromycin can be increased when combined with Efavirenz.
Estrogen and Progestin (Oral Contraceptives)	Estrogen and Progestin (Oral Contraceptives) The metabolism of Conjugated estrogens can be decreased when combined with Efavirenz.
Fenofibrate	Fenofibrate The metabolism of Fenofibrate can be decreased when combined with Efavirenz.
Guanfacine	Guanfacine The metabolism of Guanfacine can be decreased when combined with Efavirenz.
Mycophenolate	Mycophenolate The metabolism of Mycophenolic acid can be increased when combined with Efavirenz.
Naratriptan	Naratriptan The risk or severity of adverse effects can be increased when Efavirenz is combined with Naratriptan.
Paregoric	Paregoric The metabolism of Morphine can be decreased when combined with Efavirenz.
Penbutolol	Penbutolol The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Acebutolol.
Pentazocine	Pentazocine The risk or severity of adverse effects can be increased when Efavirenz is combined with Pentazocine.
Prednisone	Prednisone The metabolism of Prednisone can be decreased when combined with Efavirenz.
Ranitidine	Ranitidine The metabolism of Ranitidine can be decreased when combined with Efavirenz.
Reserpine	Reserpine Reserpine may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Rizatriptan	Rizatriptan The risk or severity of adverse effects can be increased when Efavirenz is combined with Rizatriptan.
Sumatriptan	Sumatriptan The risk or severity of adverse effects can be increased when Efavirenz is combined with Sumatriptan.
Tacrolimus	Tacrolimus The serum concentration of Tacrolimus can be increased when it is combined with Efavirenz.
Tizanidine	Tizanidine The metabolism of Tizanidine can be decreased when combined with Efavirenz.
Triamcinolone	Triamcinolone The metabolism of Triamcinolone can be decreased when combined with Efavirenz.
Zolmitriptan	Zolmitriptan The metabolism of Zolmitriptan can be decreased when combined with Efavirenz.
Famotidine Injection	Famotidine Injection The risk or severity of QTc prolongation can be increased when Famotidine is combined with Efavirenz.
Fluconazole Injection	Fluconazole Injection The risk or severity of QTc prolongation can be increased when Fluconazole is combined with Efavirenz.
Foscarnet Injection	Foscarnet Injection The risk or severity of QTc prolongation can be increased when Foscarnet is combined with Efavirenz.
Hydromorphone Injection	Hydromorphone Injection The metabolism of Hydromorphone can be decreased when combined with Efavirenz.
Interferon Beta-1b Injection	Interferon Beta-1b Injection The metabolism of Efavirenz can be decreased when combined with Interferon beta-1b.
Interferon Gamma-1b Injection	Interferon Gamma-1b Injection The metabolism of Efavirenz can be decreased when combined with Interferon gamma-1b.
Levofloxacin Injection	Levofloxacin Injection The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Levofloxacin.
Meperidine Injection	Meperidine Injection The metabolism of Efavirenz can be decreased when combined with Meperidine.
Methylprednisolone Injection	Methylprednisolone Injection The metabolism of Methylprednisolone can be decreased when combined with Efavirenz.
Metoclopramide Injection	Metoclopramide Injection The risk or severity of sedation can be increased when Metoclopramide is combined with Efavirenz.
Metronidazole Injection	Metronidazole Injection The metabolism of Metronidazole can be increased when combined with Efavirenz.
Morphine Injection	Morphine Injection The metabolism of Morphine can be decreased when combined with Efavirenz.
Zidovudine Injection	Zidovudine Injection The metabolism of Zidovudine can be decreased when combined with Efavirenz.
Altretamine	Altretamine The risk or severity of adverse effects can be increased when Amphetamine is combined with Efavirenz.
Cyclosporine	Cyclosporine The serum concentration of Cyclosporine can be decreased when it is combined with Efavirenz.
Ondansetron	Ondansetron The metabolism of Ondansetron can be increased when combined with Efavirenz.
Granisetron	Granisetron The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Granisetron.
Torsemide	Torsemide The metabolism of Torasemide can be decreased when combined with Efavirenz.
Olanzapine	Olanzapine The risk or severity of QTc prolongation can be increased when Olanzapine is combined with Efavirenz.
Alosetron	Alosetron The metabolism of Alosetron can be decreased when combined with Efavirenz.
Dofetilide	Dofetilide The metabolism of Dofetilide can be increased when combined with Efavirenz.
Entacapone	Entacapone The risk or severity of adverse effects can be increased when Entacapone is combined with Efavirenz.
Hydroxychloroquine	Hydroxychloroquine The risk or severity of QTc prolongation can be increased when Hydroxychloroquine is combined with Efavirenz.
Meloxicam	Meloxicam The metabolism of Meloxicam can be decreased when combined with Efavirenz.
Oxcarbazepine	Oxcarbazepine The risk or severity of adverse effects can be increased when Efavirenz is combined with Oxcarbazepine.
Pantoprazole	Pantoprazole The metabolism of Pantoprazole can be decreased when combined with Efavirenz.
Telmisartan	Telmisartan Efavirenz may decrease the excretion rate of Telmisartan which could result in a higher serum level.
Zaleplon	Zaleplon The metabolism of Zaleplon can be increased when combined with Efavirenz.
Anakinra	Anakinra The metabolism of Efavirenz can be increased when combined with Anakinra.
Desloratadine	Desloratadine The risk or severity of adverse effects can be increased when Efavirenz is combined with Desloratadine.
Linezolid	Linezolid The risk or severity of adverse effects can be increased when Linezolid is combined with Efavirenz.
Trimipramine	Trimipramine The metabolism of Trimipramine can be decreased when combined with Efavirenz.
Etanercept Injection	Etanercept Injection The metabolism of Efavirenz can be increased when combined with Etanercept.
Glycopyrrolate	Glycopyrrolate Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Glycopyrronium.
Modafinil	Modafinil The metabolism of Efavirenz can be increased when combined with Modafinil.
Tenofovir	Tenofovir The metabolism of Tenofovir can be decreased when combined with Efavirenz.
Sirolimus	Sirolimus The metabolism of Sirolimus can be increased when combined with Efavirenz.
Dutasteride	Dutasteride The metabolism of Dutasteride can be increased when combined with Efavirenz.
Epinephrine Injection	Epinephrine Injection The risk or severity of adverse effects can be increased when Efavirenz is combined with Epinephrine.
Eplerenone	Eplerenone The metabolism of Eplerenone can be decreased when combined with Efavirenz.
Escitalopram	Escitalopram The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Escitalopram.
Olmesartan	Olmesartan Olmesartan may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Zonisamide	Zonisamide The serum concentration of Zonisamide can be decreased when it is combined with Efavirenz.
Adalimumab Injection	Adalimumab Injection The metabolism of Efavirenz can be increased when combined with Adalimumab.
Aripiprazole	Aripiprazole The metabolism of Aripiprazole can be increased when combined with Efavirenz.
Atomoxetine	Atomoxetine The risk or severity of adverse effects can be increased when Atomoxetine is combined with Efavirenz.
Dexmethylphenidate	Dexmethylphenidate The risk or severity of adverse effects can be increased when Efavirenz is combined with Dexmethylphenidate.
Ezetimibe	Ezetimibe The metabolism of Ezetimibe can be increased when combined with Efavirenz.
Atazanavir	Atazanavir The serum concentration of Atazanavir can be decreased when it is combined with Efavirenz.
Almotriptan	Almotriptan The metabolism of Almotriptan can be decreased when combined with Efavirenz.
Eletriptan	Eletriptan The risk or severity of adverse effects can be increased when Eletriptan is combined with Efavirenz.
Mefloquine	Mefloquine The risk or severity of QTc prolongation can be increased when Mefloquine is combined with Efavirenz.
Rosuvastatin	Rosuvastatin The metabolism of Rosuvastatin can be decreased when combined with Efavirenz.
Vardenafil	Vardenafil The metabolism of Vardenafil can be decreased when combined with Efavirenz.
Alfuzosin	Alfuzosin The metabolism of Alfuzosin can be decreased when combined with Efavirenz.
Aprepitant	Aprepitant The metabolism of Aprepitant can be increased when combined with Efavirenz.
Interferon Beta-1a Subcutaneous Injection	Interferon Beta-1a Subcutaneous Injection The metabolism of Efavirenz can be decreased when combined with Interferon beta-1a.
Memantine	Memantine The metabolism of Efavirenz can be decreased when combined with Memantine.
Tegaserod	Tegaserod The metabolism of Efavirenz can be decreased when combined with Tegaserod.
Tadalafil	Tadalafil The serum concentration of Tadalafil can be increased when it is combined with Efavirenz.
Fosamprenavir	Fosamprenavir The serum concentration of the active metabolites of Fosamprenavir can be reduced when Fosamprenavir is used in combination with Efavirenz resulting in a loss in efficacy.
Frovatriptan	Frovatriptan The metabolism of Frovatriptan can be decreased when combined with Efavirenz.
Gemifloxacin	Gemifloxacin The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Gemifloxacin.
Progesterone	Progesterone The metabolism of Progesterone can be increased when combined with Efavirenz.
Apomorphine Injection	Apomorphine Injection The risk or severity of QTc prolongation can be increased when Apomorphine is combined with Efavirenz.
Infliximab Injection	Infliximab Injection The metabolism of Efavirenz can be increased when combined with Infliximab.
Protriptyline	Protriptyline The risk or severity of adverse effects can be increased when Efavirenz is combined with Protriptyline.
Duloxetine	Duloxetine The metabolism of Duloxetine can be decreased when combined with Efavirenz.
Norethindrone	Norethindrone The metabolism of Norethisterone can be decreased when combined with Efavirenz.
Tinidazole	Tinidazole Efavirenz may decrease the excretion rate of Tinidazole which could result in a higher serum level.
Trospium	Trospium Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Trospium.
Bosentan	Bosentan The metabolism of Bosentan can be decreased when combined with Efavirenz.
Cinacalcet	Cinacalcet The metabolism of Cinacalcet can be decreased when combined with Efavirenz.
Erlotinib	Erlotinib The serum concentration of Erlotinib can be decreased when it is combined with Efavirenz.
Eszopiclone	Eszopiclone The risk or severity of CNS depression can be increased when Efavirenz is combined with Eszopiclone.
Ganciclovir	Ganciclovir The risk or severity of adverse effects can be increased when Efavirenz is combined with Ganciclovir.
Solifenacin	Solifenacin The risk or severity of QTc prolongation can be increased when Solifenacin is combined with Efavirenz.
Voriconazole	Voriconazole The metabolism of Voriconazole can be increased when combined with Efavirenz.
Dextroamphetamine	Dextroamphetamine The risk or severity of adverse effects can be increased when Amphetamine is combined with Efavirenz.
Entecavir	Entecavir The metabolism of Entecavir can be decreased when combined with Efavirenz.
Peginterferon Alfa-2a Injection	Peginterferon Alfa-2a Injection The metabolism of Efavirenz can be decreased when combined with Peginterferon alfa-2a.
Peginterferon Alfa-2b (PEG-Intron)	Peginterferon Alfa-2b (PEG-Intron) The serum concentration of Efavirenz can be increased when it is combined with Peginterferon alfa-2b.
Sodium Oxybate	Sodium Oxybate Sodium oxybate may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Ibandronate	Ibandronate The risk or severity of QTc prolongation can be increased when Ibandronate is combined with Efavirenz.
Isocarboxazid	Isocarboxazid The risk or severity of adverse effects can be increased when Efavirenz is combined with Isocarboxazid.
Ramelteon	Ramelteon The metabolism of Ramelteon can be decreased when combined with Efavirenz.
Darifenacin	Darifenacin Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Darifenacin.
Fentanyl	Fentanyl The metabolism of Fentanyl can be decreased when combined with Efavirenz.
Pregabalin	Pregabalin The therapeutic efficacy of Efavirenz can be increased when used in combination with Pregabalin.
Deferasirox	Deferasirox The metabolism of Deferasirox can be increased when combined with Efavirenz.
Phenylephrine	Phenylephrine The metabolism of Efavirenz can be increased when combined with Phenylephrine.
Tipranavir	Tipranavir Tipranavir may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Felbamate	Felbamate The risk or severity of QTc prolongation can be increased when Felbamate is combined with Efavirenz.
Ranolazine	Ranolazine The metabolism of Efavirenz can be decreased when combined with Ranolazine.
Abatacept Injection	Abatacept Injection The metabolism of Efavirenz can be increased when combined with Abatacept.
Rasagiline	Rasagiline The metabolism of Rasagiline can be decreased when combined with Efavirenz.
Imatinib	Imatinib The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Imatinib.
Sitagliptin	Sitagliptin The metabolism of Sitagliptin can be decreased when combined with Efavirenz.
Gefitinib	Gefitinib The metabolism of Gefitinib can be increased when combined with Efavirenz.
Albuterol	Albuterol The risk or severity of QTc prolongation can be increased when Salbutamol is combined with Efavirenz.
Paliperidone	Paliperidone The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Paliperidone.
Bortezomib	Bortezomib The metabolism of Bortezomib can be decreased when combined with Efavirenz.
Influenza Vaccine, Live Intranasal	Influenza Vaccine, Live Intranasal The therapeutic efficacy of Typhoid Vaccine Live can be decreased when used in combination with Efavirenz.
Live Shingles (Zoster) Vaccine (ZVL)	Live Shingles (Zoster) Vaccine (ZVL) The therapeutic efficacy of Varicella Zoster Vaccine (Live/attenuated) can be decreased when used in combination with Efavirenz.
Fulvestrant Injection	Fulvestrant Injection The metabolism of Fulvestrant can be increased when combined with Efavirenz.
Insulin Glulisine (rDNA origin) Injection	Insulin Glulisine (rDNA origin) Injection The metabolism of Efavirenz can be increased when combined with Insulin glulisine.
Oxaliplatin Injection	Oxaliplatin Injection The risk or severity of QTc prolongation can be increased when Oxaliplatin is combined with Efavirenz.
Posaconazole	Posaconazole The serum concentration of Posaconazole can be decreased when it is combined with Efavirenz.
Primaquine	Primaquine The metabolism of Efavirenz can be increased when combined with Primaquine.
Darunavir	Darunavir The serum concentration of Efavirenz can be increased when it is combined with Darunavir.
Pemetrexed Injection	Pemetrexed Injection The metabolism of Pemetrexed can be decreased when combined with Efavirenz.
Dimenhydrinate	Dimenhydrinate The risk or severity of adverse effects can be increased when Efavirenz is combined with Dimenhydrinate.
Nabilone	Nabilone Nabilone may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Retapamulin	Retapamulin The metabolism of Retapamulin can be decreased when combined with Efavirenz.
Vorinostat	Vorinostat The risk or severity of QTc prolongation can be increased when Vorinostat is combined with Efavirenz.
Sorafenib	Sorafenib The metabolism of Sorafenib can be increased when combined with Efavirenz.
Sunitinib	Sunitinib The metabolism of Sunitinib can be increased when combined with Efavirenz.
Dronabinol	Dronabinol Dronabinol may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Lapatinib	Lapatinib The metabolism of Lapatinib can be decreased when combined with Efavirenz.
Levocetirizine	Levocetirizine The risk or severity of QTc prolongation can be increased when Levocetirizine is combined with Efavirenz.
Dasatinib	Dasatinib The metabolism of Dasatinib can be decreased when combined with Efavirenz.
Mexiletine	Mexiletine The metabolism of Mexiletine can be decreased when combined with Efavirenz.
Armodafinil	Armodafinil The metabolism of Efavirenz can be increased when combined with Armodafinil.
Temsirolimus	Temsirolimus The metabolism of Temsirolimus can be increased when combined with Efavirenz.
Maraviroc	Maraviroc The serum concentration of Maraviroc can be decreased when it is combined with Efavirenz.
Nilotinib	Nilotinib The metabolism of Nilotinib can be decreased when combined with Efavirenz.
Toremifene	Toremifene The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Toremifene.
Raltegravir	Raltegravir The metabolism of Raltegravir can be increased when combined with Efavirenz.
Bexarotene	Bexarotene The metabolism of Bexarotene can be decreased when combined with Efavirenz.
Budesonide	Budesonide The metabolism of Budesonide can be decreased when combined with Efavirenz.
OnabotulinumtoxinA Injection	OnabotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Efavirenz.
RimabotulinumtoxinB Injection	RimabotulinumtoxinB Injection The risk or severity of adverse effects can be increased when Botulinum Toxin Type B is combined with Efavirenz.
Etravirine	Etravirine The metabolism of Etravirine can be decreased when combined with Efavirenz.
Arsenic Trioxide Injection	Arsenic Trioxide Injection The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Arsenic trioxide.
Desvenlafaxine	Desvenlafaxine The risk or severity of adverse effects can be increased when Efavirenz is combined with Desvenlafaxine.
Nebivolol	Nebivolol The metabolism of Nebivolol can be decreased when combined with Efavirenz.
Tretinoin	Tretinoin The metabolism of Tretinoin can be increased when combined with Efavirenz.
Bendamustine Injection	Bendamustine Injection The metabolism of Bendamustine can be decreased when combined with Efavirenz.
Flecainide	Flecainide The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Flecainide.
Certolizumab Injection	Certolizumab Injection The metabolism of Efavirenz can be increased when combined with Certolizumab pegol.
Ixabepilone Injection	Ixabepilone Injection The metabolism of Ixabepilone can be increased when combined with Efavirenz.
Irinotecan Injection	Irinotecan Injection The serum concentration of SN-38, an active metabolite of Irinotecan, can be increased when used in combination with Efavirenz.
Praziquantel	Praziquantel The metabolism of Praziquantel can be increased when combined with Efavirenz.
Rufinamide	Rufinamide The risk or severity of adverse effects can be increased when Rufinamide is combined with Efavirenz.
Midazolam	Midazolam The serum concentration of Midazolam can be increased when it is combined with Efavirenz.
Naltrexone Injection	Naltrexone Injection The metabolism of Naltrexone can be increased when combined with Efavirenz.
Eltrombopag	Eltrombopag The metabolism of Eltrombopag can be increased when combined with Efavirenz.
Milnacipran	Milnacipran The metabolism of Milnacipran can be decreased when combined with Efavirenz.
Dexlansoprazole	Dexlansoprazole The metabolism of Dexlansoprazole can be decreased when combined with Efavirenz.
Fesoterodine	Fesoterodine The metabolism of Fesoterodine can be decreased when combined with Efavirenz.
Degarelix Injection	Degarelix Injection The risk or severity of QTc prolongation can be increased when Degarelix is combined with Efavirenz.
Betaxolol	Betaxolol The risk or severity of QTc prolongation can be increased when Betaxolol is combined with Efavirenz.
Iloperidone	Iloperidone The metabolism of Iloperidone can be decreased when combined with Efavirenz.
Prasugrel	Prasugrel The metabolism of Prasugrel can be decreased when combined with Efavirenz.
Lacosamide	Lacosamide The metabolism of Lacosamide can be decreased when combined with Efavirenz.
Everolimus	Everolimus The serum concentration of Everolimus can be decreased when it is combined with Efavirenz.
Tolvaptan (low blood sodium)	Tolvaptan (low blood sodium) The metabolism of Tolvaptan can be increased when combined with Efavirenz.
Dronedarone	Dronedarone The metabolism of Dronedarone can be decreased when combined with Efavirenz.
AbobotulinumtoxinA Injection	AbobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Efavirenz.
Palonosetron Injection	Palonosetron Injection The risk or severity of adverse effects can be increased when Palonosetron is combined with Efavirenz.
Saxagliptin	Saxagliptin The metabolism of Saxagliptin can be decreased when combined with Efavirenz.
Telavancin Injection	Telavancin Injection The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Telavancin.
Romidepsin Injection	Romidepsin Injection The metabolism of Romidepsin can be increased when combined with Efavirenz.
Tapentadol	Tapentadol Tapentadol may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Golimumab Injection	Golimumab Injection The metabolism of Efavirenz can be increased when combined with Golimumab.
Pazopanib	Pazopanib The metabolism of Pazopanib can be decreased when combined with Efavirenz.
Asenapine	Asenapine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Asenapine.
Vigabatrin	Vigabatrin The risk or severity of adverse effects can be increased when Efavirenz is combined with Vigabatrin.
Pitavastatin	Pitavastatin The metabolism of Pitavastatin can be decreased when combined with Efavirenz.
Albendazole	Albendazole The metabolism of Albendazole can be decreased when combined with Efavirenz.
Ulipristal	Ulipristal The metabolism of Ulipristal can be increased when combined with Efavirenz.
Levonorgestrel	Levonorgestrel The metabolism of Levonorgestrel can be increased when combined with Efavirenz.
Oxymorphone	Oxymorphone The risk or severity of adverse effects can be increased when Efavirenz is combined with Oxymorphone.
Tocilizumab Injection	Tocilizumab Injection The metabolism of Efavirenz can be increased when combined with Tocilizumab.
Eribulin Injection	Eribulin Injection The risk or severity of QTc prolongation can be increased when Eribulin is combined with Efavirenz.
IncobotulinumtoxinA Injection	IncobotulinumtoxinA Injection The risk or severity of adverse effects can be increased when Botulinum toxin type A is combined with Efavirenz.
Cabazitaxel Injection	Cabazitaxel Injection The metabolism of Cabazitaxel can be decreased when combined with Efavirenz.
Lurasidone	Lurasidone The risk or severity of adverse effects can be increased when Efavirenz is combined with Lurasidone.
Acetaminophen Injection	Acetaminophen Injection The metabolism of Acetaminophen can be decreased when combined with Efavirenz.
Vilazodone	Vilazodone The metabolism of Vilazodone can be decreased when combined with Efavirenz.
Terbutaline Injection	Terbutaline Injection The risk or severity of QTc prolongation can be increased when Terbutaline is combined with Efavirenz.
Busulfan Injection	Busulfan Injection The metabolism of Busulfan can be increased when combined with Efavirenz.
Roflumilast	Roflumilast The metabolism of Roflumilast can be decreased when combined with Efavirenz.
Linagliptin	Linagliptin The metabolism of Linagliptin can be decreased when combined with Efavirenz.
Rilpivirine	Rilpivirine The metabolism of Efavirenz can be decreased when combined with Rilpivirine.
Cyclophosphamide Injection	Cyclophosphamide Injection The metabolism of Cyclophosphamide can be increased when combined with Efavirenz.
Abiraterone	Abiraterone The serum concentration of Abiraterone can be increased when it is combined with Efavirenz.
Triptorelin Injection	Triptorelin Injection The risk or severity of QTc prolongation can be increased when Triptorelin is combined with Efavirenz.
Rivaroxaban	Rivaroxaban The metabolism of Rivaroxaban can be increased when combined with Efavirenz.
Brentuximab Vedotin Injection	Brentuximab Vedotin Injection The metabolism of Brentuximab vedotin can be increased when combined with Efavirenz.
Ruxolitinib	Ruxolitinib The metabolism of Ruxolitinib can be decreased when combined with Efavirenz.
Vandetanib	Vandetanib The metabolism of Vandetanib can be increased when combined with Efavirenz.
Clobazam	Clobazam The metabolism of Efavirenz can be decreased when combined with Clobazam.
Vemurafenib	Vemurafenib The serum concentration of Vemurafenib can be increased when it is combined with Efavirenz.
Vismodegib	Vismodegib The metabolism of Vismodegib can be decreased when combined with Efavirenz.
Ivacaftor	Ivacaftor The metabolism of Ivacaftor can be decreased when combined with Efavirenz.
Axitinib	Axitinib The metabolism of Axitinib can be decreased when combined with Efavirenz.
Crizotinib	Crizotinib The metabolism of Crizotinib can be increased when combined with Efavirenz.
Cabergoline	Cabergoline The metabolism of Efavirenz can be increased when combined with Cabergoline.
Naloxone Injection	Naloxone Injection The metabolism of Naloxone can be increased when combined with Efavirenz.
Ambrisentan	Ambrisentan The metabolism of Ambrisentan can be increased when combined with Efavirenz.
Ezogabine	Ezogabine The risk or severity of adverse effects can be increased when Efavirenz is combined with Tiagabine.
Enzalutamide	Enzalutamide The metabolism of Enzalutamide can be increased when combined with Efavirenz.
Mirabegron	Mirabegron The risk or severity of QTc prolongation can be increased when Mirabegron is combined with Efavirenz.
Regorafenib	Regorafenib The metabolism of Efavirenz can be increased when combined with Regorafenib.
Bosutinib	Bosutinib The metabolism of Bosutinib can be increased when combined with Efavirenz.
Corticotropin, Repository Injection	Corticotropin, Repository Injection The metabolism of Corticotropin can be decreased when combined with Efavirenz.
Teriflunomide	Teriflunomide The serum concentration of Efavirenz can be decreased when it is combined with Teriflunomide.
Cabozantinib (thyroid cancer)	Cabozantinib (thyroid cancer) The metabolism of Cabozantinib can be decreased when combined with Efavirenz.
Bedaquiline	Bedaquiline The metabolism of Bedaquiline can be decreased when combined with Efavirenz.
Tofacitinib	Tofacitinib The metabolism of Tofacitinib can be decreased when combined with Efavirenz.
Ponatinib	Ponatinib The metabolism of Ponatinib can be decreased when combined with Efavirenz.
Pomalidomide	Pomalidomide The metabolism of Pomalidomide can be increased when combined with Efavirenz.
Ado-trastuzumab Emtansine Injection	Ado-trastuzumab Emtansine Injection The metabolism of Trastuzumab emtansine can be decreased when combined with Efavirenz.
Apixaban	Apixaban The metabolism of Apixaban can be increased when combined with Efavirenz.
Canagliflozin	Canagliflozin The serum concentration of Canagliflozin can be decreased when it is combined with Efavirenz.
Dabrafenib	Dabrafenib The metabolism of Efavirenz can be increased when combined with Dabrafenib.
Ospemifene	Ospemifene The metabolism of Ospemifene can be decreased when combined with Efavirenz.
Dolutegravir	Dolutegravir The metabolism of Dolutegravir can be increased when combined with Efavirenz.
Levomilnacipran	Levomilnacipran The metabolism of Levomilnacipran can be decreased when combined with Efavirenz.
Vortioxetine	Vortioxetine The metabolism of Vortioxetine can be increased when combined with Efavirenz.
Perampanel	Perampanel The metabolism of Perampanel can be increased when combined with Efavirenz.
Ibrutinib	Ibrutinib The metabolism of Ibrutinib can be decreased when combined with Efavirenz.
Lomitapide	Lomitapide The metabolism of Lomitapide can be increased when combined with Efavirenz.
Ketorolac Injection	Ketorolac Injection The metabolism of Ketorolac can be decreased when combined with Efavirenz.
Simeprevir	Simeprevir The metabolism of Efavirenz can be decreased when combined with Simeprevir.
Dapagliflozin	Dapagliflozin The metabolism of Dapagliflozin can be decreased when combined with Efavirenz.
Apremilast	Apremilast The metabolism of Efavirenz can be increased when combined with Apremilast.
Ceritinib	Ceritinib The metabolism of Ceritinib can be decreased when combined with Efavirenz.
Siltuximab Injection	Siltuximab Injection The metabolism of Efavirenz can be increased when combined with Siltuximab.
Eslicarbazepine	Eslicarbazepine The metabolism of Eslicarbazepine can be increased when combined with Efavirenz.
Belinostat Injection	Belinostat Injection The metabolism of Belinostat can be increased when combined with Efavirenz.
Idelalisib	Idelalisib The metabolism of Idelalisib can be increased when combined with Efavirenz.
Testosterone Injection	Testosterone Injection The metabolism of Testosterone can be increased when combined with Efavirenz.
Vorapaxar	Vorapaxar The metabolism of Vorapaxar can be decreased when combined with Efavirenz.
Hydrocodone	Hydrocodone The metabolism of Hydrocodone can be decreased when combined with Efavirenz.
Suvorexant	Suvorexant Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Suvorexant.
Peginterferon Beta-1a Injection	Peginterferon Beta-1a Injection The metabolism of Efavirenz can be decreased when combined with Peginterferon beta-1a.
Olaparib	Olaparib The metabolism of Olaparib can be decreased when combined with Efavirenz.
Methamphetamine	Methamphetamine The risk or severity of adverse effects can be increased when Efavirenz is combined with Metamfetamine.
Tasimelteon	Tasimelteon The metabolism of Tasimelteon can be decreased when combined with Efavirenz.
Riociguat	Riociguat The serum concentration of Riociguat can be increased when it is combined with Efavirenz.
Pirfenidone	Pirfenidone The metabolism of Pirfenidone can be decreased when combined with Efavirenz.
Nintedanib	Nintedanib The metabolism of Nintedanib can be decreased when combined with Efavirenz.
Secukinumab Injection	Secukinumab Injection The metabolism of Efavirenz can be increased when combined with Secukinumab.
Risperidone Injection	Risperidone Injection The metabolism of Risperidone can be increased when combined with Efavirenz.
Palbociclib	Palbociclib The metabolism of Palbociclib can be decreased when combined with Efavirenz.
Insulin Human Inhalation	Insulin Human Inhalation The metabolism of Efavirenz can be increased when combined with Insulin human.
Lenvatinib	Lenvatinib The metabolism of Efavirenz can be decreased when combined with Lenvatinib.
Panobinostat	Panobinostat The metabolism of Panobinostat can be decreased when combined with Efavirenz.
Haloperidol Injection	Haloperidol Injection The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Haloperidol.
Deoxycholic Acid Injection	Deoxycholic Acid Injection Deoxycholic acid may increase the excretion rate of Efavirenz which could result in a lower serum level and potentially a reduction in efficacy.
Ivabradine	Ivabradine Ivabradine may increase the QTc-prolonging activities of Efavirenz.
Isavuconazonium Injection	Isavuconazonium Injection The serum concentration of Isavuconazonium can be increased when it is combined with Efavirenz.
Sonidegib	Sonidegib The metabolism of Sonidegib can be increased when combined with Efavirenz.
Flibanserin	Flibanserin The metabolism of Flibanserin can be decreased when combined with Efavirenz.
Rolapitant	Rolapitant The metabolism of Rolapitant can be increased when combined with Efavirenz.
Prednisolone	Prednisolone The metabolism of Prednisolone can be decreased when combined with Efavirenz.
Daclatasvir	Daclatasvir The metabolism of Daclatasvir can be increased when combined with Efavirenz.
Brexpiprazole	Brexpiprazole The metabolism of Brexpiprazole can be decreased when combined with Efavirenz.
Ziprasidone Injection	Ziprasidone Injection The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Ziprasidone.
Cariprazine	Cariprazine The risk or severity of adverse effects can be increased when Efavirenz is combined with Cariprazine.
Insulin Degludec (rDNA Origin) Injection	Insulin Degludec (rDNA Origin) Injection The metabolism of Efavirenz can be increased when combined with Insulin degludec.
Cobimetinib	Cobimetinib The metabolism of Cobimetinib can be increased when combined with Efavirenz.
Trabectedin Injection	Trabectedin Injection The metabolism of Trabectedin can be decreased when combined with Efavirenz.
Osimertinib	Osimertinib The metabolism of Osimertinib can be decreased when combined with Efavirenz.
Alectinib	Alectinib The metabolism of Alectinib can be increased when combined with Efavirenz.
Ixazomib	Ixazomib The metabolism of Ixazomib can be increased when combined with Efavirenz.
Rifapentine	Rifapentine The metabolism of Efavirenz can be increased when combined with Rifapentine.
Lesinurad	Lesinurad The metabolism of Lesinurad can be decreased when combined with Efavirenz.
Dexamethasone Injection	Dexamethasone Injection The metabolism of Efavirenz can be decreased when combined with Dexamethasone.
Brivaracetam Injection	Brivaracetam Injection The metabolism of Brivaracetam can be decreased when combined with Efavirenz.
Venetoclax	Venetoclax The metabolism of Venetoclax can be increased when combined with Efavirenz.
Cobicistat	Cobicistat The metabolism of Cobicistat can be increased when combined with Efavirenz.
Selexipag	Selexipag The metabolism of Selexipag can be decreased when combined with Efavirenz.
Pimavanserin	Pimavanserin The risk or severity of adverse effects can be increased when Efavirenz is combined with Pimavanserin.
Obeticholic Acid	Obeticholic Acid The metabolism of Efavirenz can be decreased when combined with Obeticholic acid.
Diphenhydramine Injection	Diphenhydramine Injection The risk or severity of adverse effects can be increased when Efavirenz is combined with Diphenhydramine.
Furosemide Injection	Furosemide Injection The metabolism of Furosemide can be increased when combined with Efavirenz.
Rucaparib	Rucaparib The metabolism of Rucaparib can be decreased when combined with Efavirenz.
Ribociclib	Ribociclib The metabolism of Ribociclib can be decreased when combined with Efavirenz.
Brigatinib	Brigatinib The metabolism of Brigatinib can be decreased when combined with Efavirenz.
Doxepin (Insomnia)	Doxepin (Insomnia) The metabolism of Doxepin can be decreased when combined with Efavirenz.
Deutetrabenazine	Deutetrabenazine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Deutetrabenazine.
Valbenazine	Valbenazine The metabolism of Valbenazine can be increased when combined with Efavirenz.
Deflazacort	Deflazacort The serum concentration of Deflazacort can be decreased when it is combined with Efavirenz.
Safinamide	Safinamide The metabolism of Efavirenz can be decreased when combined with Safinamide.
Midostaurin	Midostaurin The metabolism of Efavirenz can be increased when combined with Midostaurin.
Neratinib	Neratinib The serum concentration of Neratinib can be increased when it is combined with Efavirenz.
Enasidenib	Enasidenib The metabolism of Enasidenib can be increased when combined with Efavirenz.
Aprepitant/Fosaprepitant Injection	Aprepitant/Fosaprepitant Injection The metabolism of Fosaprepitant can be decreased when combined with Efavirenz.
Copanlisib Injection	Copanlisib Injection The metabolism of Copanlisib can be increased when combined with Efavirenz.
Delafloxacin	Delafloxacin The metabolism of Delafloxacin can be increased when combined with Efavirenz.
Abemaciclib	Abemaciclib The metabolism of Abemaciclib can be decreased when combined with Efavirenz.
Acalabrutinib	Acalabrutinib The metabolism of Acalabrutinib can be increased when combined with Efavirenz.
Letermovir	Letermovir The metabolism of Letermovir can be increased when combined with Efavirenz.
Tetrabenazine	Tetrabenazine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Tetrabenazine.
Buprenorphine Injection	Buprenorphine Injection Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Buprenorphine.
Apalutamide	Apalutamide The metabolism of Efavirenz can be decreased when combined with Apalutamide.
Baricitinib	Baricitinib The metabolism of Baricitinib can be increased when combined with Efavirenz.
Lofexidine	Lofexidine The therapeutic efficacy of Efavirenz can be increased when used in combination with Lofexidine.
Eliglustat	Eliglustat The metabolism of Eliglustat can be decreased when combined with Efavirenz.
Encorafenib	Encorafenib The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Encorafenib.
Binimetinib	Binimetinib The metabolism of Binimetinib can be increased when combined with Efavirenz.
Ivosidenib	Ivosidenib The metabolism of Ivosidenib can be increased when combined with Efavirenz.
Elagolix	Elagolix The metabolism of Elagolix can be increased when combined with Efavirenz.
Doravirine	Doravirine The metabolism of Doravirine can be increased when combined with Efavirenz.
Cannabidiol	Cannabidiol The risk or severity of adverse effects can be increased when Cannabidiol is combined with Efavirenz.
Dacomitinib	Dacomitinib The metabolism of Dacomitinib can be increased when combined with Efavirenz.
Duvelisib	Duvelisib The metabolism of Duvelisib can be decreased when combined with Efavirenz.
Stiripentol	Stiripentol The metabolism of Stiripentol can be decreased when combined with Efavirenz.
Gilteritinib	Gilteritinib The metabolism of Gilteritinib can be decreased when combined with Efavirenz.
Glasdegib	Glasdegib The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Glasdegib.
Lorlatinib	Lorlatinib The metabolism of Lorlatinib can be decreased when combined with Efavirenz.
Paclitaxel (with albumin) Injection	Paclitaxel (with albumin) Injection The metabolism of Paclitaxel can be increased when combined with Efavirenz.
Rifamycin	Rifamycin The metabolism of Efavirenz can be decreased when combined with Rifamycin.
Prucalopride	Prucalopride The metabolism of Prucalopride can be decreased when combined with Efavirenz.
Emapalumab-lzsg Injection	Emapalumab-lzsg Injection The metabolism of Efavirenz can be increased when combined with Emapalumab.
Siponimod	Siponimod The risk or severity of adverse effects can be increased when Efavirenz is combined with Siponimod.
Acyclovir Ophthalmic	Acyclovir Ophthalmic The metabolism of Acyclovir can be decreased when combined with Efavirenz.
Erdafitinib	Erdafitinib The metabolism of Erdafitinib can be increased when combined with Efavirenz.
Esomeprazole Injection	Esomeprazole Injection The metabolism of Esomeprazole can be decreased when combined with Efavirenz.
Alpelisib	Alpelisib The metabolism of Alpelisib can be increased when combined with Efavirenz.
Brexanolone Injection	Brexanolone Injection The risk or severity of adverse effects can be increased when Efavirenz is combined with Brexanolone.
Polatuzumab vedotin-piiq Injection	Polatuzumab vedotin-piiq Injection The risk or severity of adverse effects can be increased when Efavirenz is combined with Polatuzumab vedotin.
Solriamfetol	Solriamfetol The risk or severity of adverse effects can be increased when Efavirenz is combined with Solriamfetol.
Darolutamide	Darolutamide The serum concentration of Darolutamide can be decreased when it is combined with Efavirenz.
Triclabendazole	Triclabendazole The metabolism of Triclabendazole can be decreased when combined with Efavirenz.
Entrectinib	Entrectinib The metabolism of Entrectinib can be increased when combined with Efavirenz.
Pexidartinib	Pexidartinib The metabolism of Pexidartinib can be decreased when combined with Efavirenz.
Upadacitinib	Upadacitinib The metabolism of Upadacitinib can be decreased when combined with Efavirenz.
Istradefylline	Istradefylline The metabolism of Istradefylline can be increased when combined with Efavirenz.
Pitolisant	Pitolisant The serum concentration of Pitolisant can be decreased when it is combined with Efavirenz.
Pretomanid	Pretomanid The serum concentration of Pretomanid can be increased when it is combined with Efavirenz.
Fedratinib	Fedratinib The metabolism of Fedratinib can be decreased when combined with Efavirenz.
Lefamulin	Lefamulin Efavirenz may increase the QTc-prolonging activities of Lefamulin.
Phenytoin Injection	Phenytoin Injection The serum concentration of Efavirenz can be decreased when it is combined with Phenytoin.
Fosphenytoin Injection	Fosphenytoin Injection The serum concentration of Efavirenz can be decreased when it is combined with Fosphenytoin.
Enfortumab vedotin-ejfv Injection	Enfortumab vedotin-ejfv Injection The serum concentration of Enfortumab vedotin can be increased when it is combined with Efavirenz.
Zanubrutinib	Zanubrutinib The metabolism of Zanubrutinib can be increased when combined with Efavirenz.
Voxelotor	Voxelotor The serum concentration of Voxelotor can be increased when it is combined with Efavirenz.
Avapritinib	Avapritinib The metabolism of Avapritinib can be decreased when combined with Efavirenz.
Lumateperone	Lumateperone The serum concentration of Lumateperone can be increased when it is combined with Efavirenz.
Lasmiditan	Lasmiditan The risk or severity of adverse effects can be increased when Efavirenz is combined with Lasmiditan.
Ubrogepant	Ubrogepant The serum concentration of Ubrogepant can be increased when it is combined with Efavirenz.
Tazemetostat	Tazemetostat The metabolism of Tazemetostat can be decreased when combined with Efavirenz.
Cenobamate	Cenobamate The serum concentration of Cenobamate can be decreased when it is combined with Efavirenz.
Pemigatinib	Pemigatinib The metabolism of Pemigatinib can be increased when combined with Efavirenz.
Ozanimod	Ozanimod The metabolism of Ozanimod can be decreased when combined with Efavirenz.
Selumetinib	Selumetinib The serum concentration of Selumetinib can be increased when it is combined with Efavirenz.
Rimegepant	Rimegepant The metabolism of Rimegepant can be decreased when combined with Efavirenz.
Tucatinib	Tucatinib The metabolism of Tucatinib can be decreased when combined with Efavirenz.
Sacituzumab govitecan-hziy Injection	Sacituzumab govitecan-hziy Injection The serum concentration of Sacituzumab govitecan can be decreased when it is combined with Efavirenz.
Ripretinib	Ripretinib The serum concentration of Ripretinib can be increased when it is combined with Efavirenz.
Selpercatinib	Selpercatinib The serum concentration of Selpercatinib can be decreased when it is combined with Efavirenz.
Capmatinib	Capmatinib The serum concentration of Capmatinib can be decreased when it is combined with Efavirenz.
Lemborexant	Lemborexant The serum concentration of Lemborexant can be decreased when it is combined with Efavirenz.
Fenfluramine	Fenfluramine The risk or severity of adverse effects can be increased when Fenfluramine is combined with Efavirenz.
Fostemsavir	Fostemsavir The risk or severity of QTc prolongation can be increased when Fostemsavir is combined with Efavirenz.
Lurbinectedin Injection	Lurbinectedin Injection The serum concentration of Lurbinectedin can be decreased when it is combined with Efavirenz.
Octreotide	Octreotide The risk or severity of QTc prolongation can be increased when Octreotide is combined with Efavirenz.
Belantamab Mafodotin-blmf Injection	Belantamab Mafodotin-blmf Injection Efavirenz may decrease the excretion rate of Belantamab mafodotin which could result in a higher serum level.
Pralsetinib	Pralsetinib The serum concentration of Efavirenz can be increased when it is combined with Pralsetinib.
Satralizumab-mwge Injection	Satralizumab-mwge Injection The serum concentration of Efavirenz can be decreased when it is combined with Satralizumab.
Relugolix	Relugolix The risk or severity of QTc prolongation can be increased when Relugolix is combined with Efavirenz.
Progestin-Only (drospirenone) Oral Contraceptives	Progestin-Only (drospirenone) Oral Contraceptives The metabolism of Drospirenone can be decreased when combined with Efavirenz.
Viloxazine	Viloxazine The risk or severity of adverse effects can be increased when Efavirenz is combined with Viloxazine.
Theophylline	Theophylline The metabolism of Theophylline can be increased when combined with Efavirenz.
Indomethacin	Indomethacin The metabolism of Indomethacin can be increased when combined with Efavirenz.
Mefenamic Acid	Mefenamic Acid The metabolism of Mefenamic acid can be decreased when combined with Efavirenz.
Naproxen	Naproxen The metabolism of Naproxen can be increased when combined with Efavirenz.
Trazodone	Trazodone The risk or severity of QTc prolongation can be increased when Trazodone is combined with Efavirenz.
Phenobarbital	Phenobarbital The metabolism of Phenobarbital can be decreased when combined with Efavirenz.
Metaxalone	Metaxalone The risk or severity of adverse effects can be increased when Efavirenz is combined with Metaxalone.
Methotrexate Injection	Methotrexate Injection The metabolism of Methotrexate can be increased when combined with Efavirenz.
Levorphanol	Levorphanol The risk or severity of adverse effects can be increased when Efavirenz is combined with Levorphanol.
Primidone	Primidone The metabolism of Primidone can be increased when combined with Efavirenz.
Methsuximide	Methsuximide The serum concentration of Methsuximide can be decreased when it is combined with Efavirenz.
Diethylpropion	Diethylpropion The risk or severity of adverse effects can be increased when Efavirenz is combined with Diethylpropion.
Chlorpromazine	Chlorpromazine The metabolism of Chlorpromazine can be decreased when combined with Efavirenz.
Diazepam	Diazepam The metabolism of Diazepam can be increased when combined with Efavirenz.
Oxazepam	Oxazepam The risk or severity of adverse effects can be increased when Efavirenz is combined with Oxazepam.
Flurazepam	Flurazepam The risk or severity of adverse effects can be increased when Efavirenz is combined with Flurazepam.
Clorazepate	Clorazepate The risk or severity of adverse effects can be increased when Efavirenz is combined with Clorazepic acid.
Lorazepam	Lorazepam The metabolism of Lorazepam can be decreased when combined with Efavirenz.
Carmustine	Carmustine The metabolism of Carmustine can be decreased when combined with Efavirenz.
Amantadine	Amantadine The risk or severity of QTc prolongation can be increased when Amantadine is combined with Efavirenz.
Codeine	Codeine The risk or severity of adverse effects can be increased when Codeine is combined with Efavirenz.
Meprobamate	Meprobamate The risk or severity of adverse effects can be increased when Meprobamate is combined with Efavirenz.
Chlordiazepoxide	Chlordiazepoxide The risk or severity of adverse effects can be increased when Chlordiazepoxide is combined with Efavirenz.
Bromocriptine	Bromocriptine The risk or severity of adverse effects can be increased when Efavirenz is combined with Bromocriptine.
Tranylcypromine	Tranylcypromine The risk or severity of adverse effects can be increased when Efavirenz is combined with Tranylcypromine.
Phenelzine	Phenelzine The risk or severity of adverse effects can be increased when Efavirenz is combined with Phenelzine.
Procarbazine	Procarbazine The risk or severity of adverse effects can be increased when Efavirenz is combined with Procarbazine.
Ergoloid Mesylates	Ergoloid Mesylates The risk or severity of adverse effects can be increased when Efavirenz is combined with Ergoloid mesylate.
Minocycline	Minocycline Minocycline may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Prochlorperazine	Prochlorperazine The metabolism of Prochlorperazine can be decreased when combined with Efavirenz.
Thioridazine	Thioridazine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Thioridazine.
Trifluoperazine	Trifluoperazine The risk or severity of adverse effects can be increased when Efavirenz is combined with Trifluoperazine.
Dapsone	Dapsone The metabolism of Dapsone can be increased when combined with Efavirenz.
Sulfadiazine	Sulfadiazine The metabolism of Sulfadiazine can be decreased when combined with Efavirenz.
Oxycodone	Oxycodone The metabolism of Oxycodone can be increased when combined with Efavirenz.
Methadone	Methadone The risk or severity of adverse effects can be increased when Methadone is combined with Efavirenz.
Oxybutynin	Oxybutynin The metabolism of Oxybutynin can be increased when combined with Efavirenz.
Benztropine	Benztropine The risk or severity of QTc prolongation can be increased when Benzatropine is combined with Efavirenz.
Maprotiline	Maprotiline The metabolism of Maprotiline can be decreased when combined with Efavirenz.
Ibuprofen	Ibuprofen The metabolism of Ibuprofen can be decreased when combined with Efavirenz.
Trihexyphenidyl	Trihexyphenidyl Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Trihexyphenidyl.
Orphenadrine	Orphenadrine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Orphenadrine.
Perphenazine	Perphenazine The metabolism of Perphenazine can be decreased when combined with Efavirenz.
Azathioprine	Azathioprine The metabolism of Azathioprine can be decreased when combined with Efavirenz.
Fluphenazine	Fluphenazine The risk or severity of adverse effects can be increased when Fluphenazine is combined with Efavirenz.
Phentermine	Phentermine The metabolism of Phentermine can be decreased when combined with Efavirenz.
Amoxapine	Amoxapine The risk or severity of adverse effects can be increased when Efavirenz is combined with Amoxapine.
Hydrocortisone	Hydrocortisone The metabolism of Hydrocortisone can be decreased when combined with Efavirenz.
Doxorubicin	Doxorubicin The metabolism of Efavirenz can be increased when combined with Doxorubicin.
Cytarabine	Cytarabine The risk or severity of adverse effects can be increased when Efavirenz is combined with Cytarabine.
Carbamazepine	Carbamazepine The metabolism of Carbamazepine can be increased when combined with Efavirenz.
Molindone	Molindone The risk or severity of adverse effects can be increased when Efavirenz is combined with Molindone.
Clonidine	Clonidine The risk or severity of sedation can be increased when Clonidine is combined with Efavirenz.
Prazosin	Prazosin The risk or severity of adverse effects can be increased when Efavirenz is combined with Prazosin.
Cimetidine	Cimetidine Cimetidine may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Warfarin	Warfarin The metabolism of Warfarin can be increased when combined with Efavirenz.
Clonazepam	Clonazepam The metabolism of Clonazepam can be increased when combined with Efavirenz.
Loperamide	Loperamide The serum concentration of Loperamide can be decreased when it is combined with Efavirenz.
Promethazine	Promethazine The risk or severity of adverse effects can be increased when Efavirenz is combined with Promethazine.
Daunorubicin	Daunorubicin Efavirenz may decrease the excretion rate of Daunorubicin which could result in a higher serum level.
Nitrofurantoin	Nitrofurantoin Efavirenz may decrease the excretion rate of Nitrofurantoin which could result in a higher serum level.
Griseofulvin	Griseofulvin The metabolism of Efavirenz can be increased when combined with Griseofulvin.
Digoxin	Digoxin Efavirenz may decrease the excretion rate of Digoxin which could result in a higher serum level.
Loxapine	Loxapine The risk or severity of adverse effects can be increased when Loxapine is combined with Efavirenz.
Chloroquine	Chloroquine The metabolism of Chloroquine can be increased when combined with Efavirenz.
Quinine	Quinine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Quinine.
Ethosuximide	Ethosuximide The serum concentration of Ethosuximide can be decreased when it is combined with Efavirenz.
Triamterene	Triamterene The metabolism of Triamterene can be decreased when combined with Efavirenz.
Sulfinpyrazone	Sulfinpyrazone The metabolism of Efavirenz can be increased when combined with Sulfinpyrazone.
Isosorbide	Isosorbide The metabolism of Isosorbide can be increased when combined with Efavirenz.
Clindamycin Injection	Clindamycin Injection The metabolism of Clindamycin can be increased when combined with Efavirenz.
Secobarbital	Secobarbital The risk or severity of adverse effects can be increased when Secobarbital is combined with Efavirenz.
Desipramine	Desipramine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Desipramine.
Amitriptyline	Amitriptyline The metabolism of Efavirenz can be decreased when combined with Amitriptyline.
Imipramine	Imipramine The metabolism of Imipramine can be increased when combined with Efavirenz.
Quinidine	Quinidine The metabolism of Quinidine can be increased when combined with Efavirenz.
Procainamide	Procainamide The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Procainamide.
Isoniazid	Isoniazid The metabolism of Efavirenz can be decreased when combined with Isoniazid.
Rifampin	Rifampin The metabolism of Efavirenz can be increased when combined with Rifampicin.
Disopyramide	Disopyramide The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Disopyramide.
Valproic Acid	Valproic Acid The metabolism of Valproic acid can be increased when combined with Efavirenz.
Tamoxifen	Tamoxifen The metabolism of Tamoxifen can be increased when combined with Efavirenz.
Butabarbital	Butabarbital The risk or severity of adverse effects can be increased when Butabarbital is combined with Efavirenz.
Levothyroxine	Levothyroxine The metabolism of Levothyroxine can be increased when combined with Efavirenz.
Liothyronine	Liothyronine The metabolism of Liothyronine can be increased when combined with Efavirenz.
Methimazole	Methimazole The metabolism of Efavirenz can be decreased when combined with Methimazole.
Chlorpropamide	Chlorpropamide The metabolism of Chlorpropamide can be decreased when combined with Efavirenz.
Tolbutamide	Tolbutamide The metabolism of Tolbutamide can be decreased when combined with Efavirenz.
Tolazamide	Tolazamide The metabolism of Tolazamide can be decreased when combined with Efavirenz.
Dextromethorphan	Dextromethorphan The metabolism of Dextromethorphan can be increased when combined with Efavirenz.
Cyclobenzaprine	Cyclobenzaprine The risk or severity of CNS depression can be increased when Efavirenz is combined with Cyclobenzaprine.
Baclofen	Baclofen The risk or severity of adverse effects can be increased when Baclofen is combined with Efavirenz.
Doxylamine	Doxylamine Doxylamine may increase the central nervous system depressant (CNS depressant) activities of Efavirenz.
Cyproheptadine	Cyproheptadine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Cyproheptadine.
Clemastine	Clemastine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Clemastine.
Chlorpheniramine	Chlorpheniramine The metabolism of Chlorpheniramine can be increased when combined with Efavirenz.
Brompheniramine	Brompheniramine The risk or severity of adverse effects can be increased when Dexbrompheniramine is combined with Efavirenz.
Meclizine	Meclizine The risk or severity of adverse effects can be increased when Efavirenz is combined with Meclizine.
Hydrochlorothiazide	Hydrochlorothiazide The risk or severity of QTc prolongation can be increased when Hydrochlorothiazide is combined with Efavirenz.
Dantrolene	Dantrolene The risk or severity of adverse effects can be increased when Efavirenz is combined with Dantrolene.
Chlorzoxazone	Chlorzoxazone The metabolism of Chlorzoxazone can be decreased when combined with Efavirenz.
Carisoprodol	Carisoprodol The risk or severity of adverse effects can be increased when Carisoprodol is combined with Efavirenz.
Methocarbamol	Methocarbamol The risk or severity of adverse effects can be increased when Methocarbamol is combined with Efavirenz.
Disulfiram	Disulfiram The metabolism of Disulfiram can be increased when combined with Efavirenz.
Propranolol (Cardiovascular)	Propranolol (Cardiovascular) The serum concentration of Propranolol can be decreased when it is combined with Efavirenz.
Minoxidil	Minoxidil The metabolism of Minoxidil can be increased when combined with Efavirenz.
Nortriptyline	Nortriptyline The metabolism of Nortriptyline can be increased when combined with Efavirenz.
Spironolactone	Spironolactone Spironolactone may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Butorphanol Injection	Butorphanol Injection The risk or severity of adverse effects can be increased when Butorphanol is combined with Efavirenz.
Nalbuphine Injection	Nalbuphine Injection The risk or severity of adverse effects can be increased when Efavirenz is combined with Nalbuphine.
Oxytocin Injection	Oxytocin Injection The risk or severity of QTc prolongation can be increased when Oxytocin is combined with Efavirenz.
Trimethobenzamide	Trimethobenzamide The risk or severity of adverse effects can be increased when Efavirenz is combined with Trimethobenzamide.
Flavoxate	Flavoxate Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Flavoxate.
Papaverine	Papaverine The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Papaverine.
Fluorouracil Injection	Fluorouracil Injection The metabolism of Fluorouracil can be decreased when combined with Efavirenz.
Colchicine	Colchicine The metabolism of Colchicine can be decreased when combined with Efavirenz.
Cefaclor	Cefaclor Efavirenz may decrease the excretion rate of Cefaclor which could result in a higher serum level.
Cephalexin	Cephalexin The metabolism of Cephalexin can be decreased when combined with Efavirenz.
Dacarbazine	Dacarbazine The metabolism of Dacarbazine can be decreased when combined with Efavirenz.
Acetazolamide	Acetazolamide The risk or severity of adverse effects can be increased when Efavirenz is combined with Acetazolamide.
Bacillus Calmette-Guerin (BCG) Vaccine	Bacillus Calmette-Guerin (BCG) Vaccine The therapeutic efficacy of Bacillus calmette-guerin substrain tice live antigen can be decreased when used in combination with Efavirenz.
Ketoconazole	Ketoconazole The risk or severity of QTc prolongation can be increased when Ketoconazole is combined with Efavirenz.
Pyrantel	Pyrantel The risk or severity of adverse effects can be increased when Efavirenz is combined with Pyrantel.
Thiotepa Injection	Thiotepa Injection The metabolism of Efavirenz can be increased when combined with Thiotepa.
Vincristine Injection	Vincristine Injection The metabolism of Vincristine can be increased when combined with Efavirenz.
Dipyridamole	Dipyridamole Efavirenz may decrease the excretion rate of Dipyridamole which could result in a higher serum level.
Vinblastine	Vinblastine The metabolism of Efavirenz can be increased when combined with Vinblastine.
Metoprolol	Metoprolol The metabolism of Metoprolol can be decreased when combined with Efavirenz.
Hydroxyzine	Hydroxyzine The risk or severity of QTc prolongation can be increased when Hydroxyzine is combined with Efavirenz.
Thiothixene	Thiothixene The risk or severity of adverse effects can be increased when Efavirenz is combined with Thiothixene.
Aspirin	Aspirin The metabolism of Acetylsalicylic acid can be decreased when combined with Efavirenz.
Alprazolam	Alprazolam The metabolism of Alprazolam can be decreased when combined with Efavirenz.
Temazepam	Temazepam The risk or severity of adverse effects can be increased when Temazepam is combined with Efavirenz.
Triazolam	Triazolam The risk or severity of adverse effects can be increased when Efavirenz is combined with Triazolam.
Dicyclomine	Dicyclomine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Dicyclomine.
Hyoscyamine	Hyoscyamine The risk or severity of QTc prolongation can be increased when Hyoscyamine is combined with Efavirenz.
Propantheline	Propantheline Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Propantheline.
Trimethoprim	Trimethoprim The metabolism of Trimethoprim can be decreased when combined with Efavirenz.
Diltiazem	Diltiazem The serum concentration of Diltiazem can be decreased when it is combined with Efavirenz.
Nifedipine	Nifedipine The serum concentration of Nifedipine can be decreased when it is combined with Efavirenz.
Timolol	Timolol The risk or severity of QTc prolongation can be increased when Timolol is combined with Efavirenz.
Verapamil	Verapamil The serum concentration of Verapamil can be decreased when it is combined with Efavirenz.
Atenolol	Atenolol Atenolol may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Pindolol	Pindolol The risk or severity of adverse effects can be increased when Efavirenz is combined with Pindolol.
Cisplatin Injection	Cisplatin Injection The metabolism of Efavirenz can be decreased when combined with Cisplatin.
Piroxicam	Piroxicam The metabolism of Piroxicam can be decreased when combined with Efavirenz.
Streptozocin	Streptozocin The metabolism of Efavirenz can be increased when combined with Streptozocin.
Etoposide	Etoposide The metabolism of Etoposide can be increased when combined with Efavirenz.
Glyburide	Glyburide The metabolism of Glyburide can be increased when combined with Efavirenz.
Glipizide	Glipizide The metabolism of Glipizide can be increased when combined with Efavirenz.
Indapamide	Indapamide The risk or severity of QTc prolongation can be increased when Indapamide is combined with Efavirenz.
Nafcillin Injection	Nafcillin Injection The metabolism of Efavirenz can be increased when combined with Nafcillin.
Pentoxifylline	Pentoxifylline The metabolism of Pentoxifylline can be decreased when combined with Efavirenz.
Pentamidine Injection	Pentamidine Injection The metabolism of Pentamidine can be increased when combined with Efavirenz.
Labetalol	Labetalol The metabolism of Labetalol can be increased when combined with Efavirenz.
Leuprolide Injection	Leuprolide Injection The risk or severity of QTc prolongation can be increased when Leuprolide is combined with Efavirenz.
Gemfibrozil	Gemfibrozil The metabolism of Efavirenz can be decreased when combined with Gemfibrozil.
Guanabenz	Guanabenz The metabolism of Guanabenz can be decreased when combined with Efavirenz.
Ketoprofen	Ketoprofen The metabolism of Ketoprofen can be increased when combined with Efavirenz.
Pimozide	Pimozide The metabolism of Pimozide can be increased when combined with Efavirenz.
Flurbiprofen	Flurbiprofen The metabolism of Flurbiprofen can be increased when combined with Efavirenz.
Amiodarone	Amiodarone The serum concentration of Amiodarone can be decreased when it is combined with Efavirenz.
Buspirone	Buspirone The metabolism of Buspirone can be increased when combined with Efavirenz.
Lovastatin	Lovastatin The serum concentration of Lovastatin can be decreased when it is combined with Efavirenz.
Ciprofloxacin	Ciprofloxacin The metabolism of Efavirenz can be decreased when combined with Ciprofloxacin.
Diclofenac	Diclofenac The metabolism of Diclofenac can be decreased when combined with Efavirenz.
Fluoxetine	Fluoxetine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Fluoxetine.
Nimodipine	Nimodipine The serum concentration of Nimodipine can be decreased when it is combined with Efavirenz.
Interferon Alfa-2b Injection	Interferon Alfa-2b Injection The metabolism of Efavirenz can be decreased when combined with Interferon alfa-2b.
Clozapine	Clozapine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Clozapine.
Estazolam	Estazolam The risk or severity of adverse effects can be increased when Efavirenz is combined with Estazolam.
Idarubicin	Idarubicin The metabolism of Idarubicin can be decreased when combined with Efavirenz.
Ofloxacin	Ofloxacin The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Ofloxacin.
Clarithromycin	Clarithromycin The metabolism of Clarithromycin can be increased when combined with Efavirenz.
Etodolac	Etodolac The metabolism of Etodolac can be decreased when combined with Efavirenz.
Felodipine	Felodipine The serum concentration of Felodipine can be decreased when it is combined with Efavirenz.
Nabumetone	Nabumetone The metabolism of Nabumetone can be decreased when combined with Efavirenz.
Pravastatin	Pravastatin The serum concentration of Pravastatin can be decreased when it is combined with Efavirenz.
Simvastatin	Simvastatin The serum concentration of Simvastatin can be decreased when it is combined with Efavirenz.
Amlodipine	Amlodipine The serum concentration of Amlodipine can be decreased when it is combined with Efavirenz.
Teniposide Injection	Teniposide Injection The metabolism of Teniposide can be increased when combined with Efavirenz.
Itraconazole	Itraconazole The metabolism of Efavirenz can be decreased when combined with Itraconazole.
Atovaquone	Atovaquone The serum concentration of Atovaquone can be decreased when it is combined with Efavirenz.
Rifabutin	Rifabutin The metabolism of Rifabutin can be increased when combined with Efavirenz.
Sotalol	Sotalol The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Sotalol.
Zolpidem	Zolpidem Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Zolpidem.
Doxazosin	Doxazosin The metabolism of Doxazosin can be decreased when combined with Efavirenz.
Isradipine	Isradipine The serum concentration of Isradipine can be decreased when it is combined with Efavirenz.
Omeprazole	Omeprazole The metabolism of Omeprazole can be increased when combined with Efavirenz.
Cisapride	Cisapride The risk or severity of QTc prolongation can be increased when Efavirenz is combined with Cisapride.
Gabapentin	Gabapentin The risk or severity of adverse effects can be increased when Efavirenz is combined with Gabapentin.
Fluvastatin	Fluvastatin The metabolism of Fluvastatin can be increased when combined with Efavirenz.
Venlafaxine	Venlafaxine The risk or severity of QTc prolongation can be increased when Venlafaxine is combined with Efavirenz.
Famciclovir	Famciclovir The metabolism of Famciclovir can be decreased when combined with Efavirenz.
Fluvoxamine	Fluvoxamine The metabolism of Fluvoxamine can be decreased when combined with Efavirenz.
Nefazodone	Nefazodone The risk or severity of adverse effects can be increased when Efavirenz is combined with Nefazodone.
Lamotrigine	Lamotrigine The serum concentration of Lamotrigine can be decreased when it is combined with Efavirenz.
Losartan	Losartan The risk or severity of QTc prolongation can be increased when Losartan is combined with Efavirenz.
Tramadol	Tramadol The metabolism of Tramadol can be decreased when combined with Efavirenz.
Vinorelbine Injection	Vinorelbine Injection The metabolism of Vinorelbine can be increased when combined with Efavirenz.
Moexipril	Moexipril The risk or severity of QTc prolongation can be increased when Moexipril is combined with Efavirenz.
Lansoprazole	Lansoprazole The metabolism of Lansoprazole can be decreased when combined with Efavirenz.
Ifosfamide Injection	Ifosfamide Injection The metabolism of Ifosfamide can be increased when combined with Efavirenz.
Nicardipine	Nicardipine The serum concentration of Nicardipine can be decreased when it is combined with Efavirenz.
Bupropion	Bupropion The metabolism of Bupropion can be increased when combined with Efavirenz.
Ticlopidine	Ticlopidine The metabolism of Efavirenz can be decreased when combined with Ticlopidine.
Saquinavir	Saquinavir Saquinavir may increase the hepatotoxic activities of Efavirenz.
Metformin	Metformin The risk or severity of adverse effects can be increased when Efavirenz is combined with Metformin.
Nisoldipine	Nisoldipine The serum concentration of Nisoldipine can be decreased when it is combined with Efavirenz.
Riluzole	Riluzole The risk or severity of adverse effects can be increased when Efavirenz is combined with Riluzole.
Glimepiride	Glimepiride The metabolism of Glimepiride can be decreased when combined with Efavirenz.
Anastrozole	Anastrozole The metabolism of Anastrozole can be decreased when combined with Efavirenz.
Indinavir	Indinavir The serum concentration of Indinavir can be decreased when it is combined with Efavirenz.
Ritonavir	Ritonavir The risk or severity of adverse effects can be increased when Efavirenz is combined with Ritonavir.
Docetaxel Injection	Docetaxel Injection The metabolism of Docetaxel can be increased when combined with Efavirenz.
Clomipramine	Clomipramine The metabolism of Clomipramine can be increased when combined with Efavirenz.
Zafirlukast	Zafirlukast The metabolism of Zafirlukast can be decreased when combined with Efavirenz.
Mirtazapine	Mirtazapine Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Mirtazapine.
Topiramate	Topiramate The risk or severity of adverse effects can be increased when Efavirenz is combined with Topiramate.
Zileuton	Zileuton The metabolism of Zileuton can be decreased when combined with Efavirenz.
Valsartan	Valsartan The metabolism of Valsartan can be decreased when combined with Efavirenz.
Insulin Lispro Injection	Insulin Lispro Injection The metabolism of Efavirenz can be increased when combined with Insulin lispro.
Pramipexole	Pramipexole Efavirenz may increase the sedative activities of Pramipexole.
Donepezil	Donepezil The metabolism of Donepezil can be decreased when combined with Efavirenz.
Nelfinavir	Nelfinavir The metabolism of Efavirenz can be decreased when combined with Nelfinavir.
Azithromycin	Azithromycin The metabolism of Azithromycin can be decreased when combined with Efavirenz.
Loratadine	Loratadine Loratadine may decrease the excretion rate of Efavirenz which could result in a higher serum level.
Carvedilol	Carvedilol The serum concentration of Carvedilol can be decreased when it is combined with Efavirenz.
Flutamide	Flutamide The metabolism of Flutamide can be increased when combined with Efavirenz.
Selegiline	Selegiline The metabolism of Selegiline can be decreased when combined with Efavirenz.
Bicalutamide	Bicalutamide The metabolism of Bicalutamide can be increased when combined with Efavirenz.
Sertraline	Sertraline The serum concentration of Sertraline can be decreased when it is combined with Efavirenz.
Propafenone	Propafenone The metabolism of Propafenone can be decreased when combined with Efavirenz.
Raloxifene	Raloxifene The metabolism of Efavirenz can be decreased when combined with Raloxifene.
Irbesartan	Irbesartan The metabolism of Irbesartan can be decreased when combined with Efavirenz.
Ropinirole	Ropinirole The risk or severity of adverse effects can be increased when Efavirenz is combined with Ropinirole.
Finasteride	Finasteride The metabolism of Finasteride can be increased when combined with Efavirenz.
Quetiapine	Quetiapine The serum concentration of Quetiapine can be increased when it is combined with Efavirenz.
Cetirizine	Cetirizine The risk or severity of adverse effects can be increased when Cetirizine is combined with Efavirenz.
Paroxetine	Paroxetine The risk or severity of adverse effects can be increased when Efavirenz is combined with Paroxetine.
Tolcapone	Tolcapone The risk or severity of adverse effects can be increased when Tolcapone is combined with Efavirenz.
Citalopram	Citalopram The serum concentration of Citalopram can be increased when it is combined with Efavirenz.
Capecitabine	Capecitabine The metabolism of Capecitabine can be decreased when combined with Efavirenz.
Abacavir	Abacavir The metabolism of Abacavir can be increased when combined with Efavirenz.
Sildenafil	Sildenafil The metabolism of Sildenafil can be decreased when combined with Efavirenz.
Pioglitazone	Pioglitazone The metabolism of Pioglitazone can be decreased when combined with Efavirenz.
Celecoxib	Celecoxib The metabolism of Celecoxib can be decreased when combined with Efavirenz.
Rosiglitazone	Rosiglitazone The metabolism of Efavirenz can be decreased when combined with Rosiglitazone.
Tolterodine	Tolterodine The serum concentration of Tolterodine can be increased when it is combined with Efavirenz.
Thalidomide	Thalidomide Efavirenz may increase the central nervous system depressant (CNS depressant) activities of Thalidomide.
Nateglinide	Nateglinide The metabolism of Nateglinide can be increased when combined with Efavirenz.
Galantamine	Galantamine The risk or severity of QTc prolongation can be increased when Galantamine is combined with Efavirenz.
Levetiracetam	Levetiracetam The risk or severity of adverse effects can be increased when Efavirenz is combined with Levetiracetam.
Rabeprazole	Rabeprazole The metabolism of Rabeprazole can be increased when combined with Efavirenz.
Terbinafine	Terbinafine The metabolism of Terbinafine can be decreased when combined with Efavirenz.