Efavirenz, Lamivudine, and Tenofovir
Efavirenz, lamivudine, and tenofovir is a three-drug combination antiviral used as a complete treatment regimen for HIV-1 infection in adults and children weighing at least 40 kg.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 3 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Important warning for people who also have hepatitis B: If you are infected with both HIV and hepatitis B virus (HBV), stopping this medication can cause a sudden, severe worsening of your hepatitis B — sometimes serious enough to be life-threatening. This has happened in people who stopped taking lamivudine or tenofovir, two of the three drugs in this tablet. If you need to stop this medication for any reason, your liver must be monitored closely for several months afterward. Your doctor may need to start a specific hepatitis B treatment to protect your liver.
📖 Efavirenz, Lamivudine, and Tenofovir: Patient Information Guide
A plain-language walkthrough of Efavirenz, Lamivudine, and Tenofovir — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
This three-drug combination is approved to treat HIV-1 infection as a complete antiviral regimen.
- Symfi (efavirenz, lamivudine, and tenofovir disoproxil fumarate tablet): approved for the treatment of HIV-1 infection in adults and pediatric patients weighing at least 40 kg (about 88 lbs)
- Lamivudine and Tenofovir Disoproxil Fumarate (the combination generic tablet): approved for the treatment of HIV-1 infection in adults and pediatric patients weighing at least 40 kg
- Both products deliver all three active ingredients in a single daily tablet, so no other HIV antiretroviral medications should be added to the regimen
⚙️How it works▾
This medication combines three antivirals that each block HIV's reverse transcriptase — the enzyme the virus uses to copy its genetic material and infect new cells. Efavirenz (an NNRTI) latches onto the enzyme directly and shuts it down. Lamivudine and tenofovir (both NRTIs) mimic normal DNA building blocks, get inserted into the growing viral DNA chain, and cause it to stop — like putting a broken puzzle piece in place that nothing else can connect to. With all three drugs working together, HIV struggles to replicate and the virus load in the body drops.
HIV can develop resistance mutations over time, which is why consistent daily use without missing doses is critical to keeping the virus suppressed.
💊How it's taken▾
These tablets are taken once daily by mouth. They should be taken on an empty stomach, and bedtime dosing is recommended because common nervous system side effects like dizziness and abnormal dreams tend to be less noticeable while sleeping. Do not take with other HIV antiretroviral medications — this tablet is already a complete regimen.
- Swallow the tablet whole — patients must be able to swallow a solid tablet
- Not for use in patients with severely reduced kidney function (creatinine clearance below 50 mL/min) or those requiring hemodialysis, because the fixed dose cannot be adjusted
- Not recommended in moderate or severe liver impairment
🤒Side effects — in detail▾
The most common side effects reported with this regimen include:
- Rash — often mild, starting within the first 1–2 weeks and typically clearing within a month
- Dizziness, especially early in treatment
- Trouble sleeping or abnormal/vivid dreams
- Difficulty concentrating
- Headache
- Diarrhea, nausea, or stomach upset
- Fatigue or general weakness
Serious reactions to watch for include severe skin reactions with blistering or peeling, signs of psychiatric effects (severe depression, suicidal thoughts, paranoia), signs of lactic acidosis (muscle pain, rapid breathing, stomach pain), or kidney problems (decreased urination, bone pain). Seek medical care right away for any of these.
⚠️Warnings & precautions▾
- Hepatitis B flare-up after stopping: People co-infected with hepatitis B and HIV can develop a dangerous worsening of hepatitis B if this medication is discontinued. Liver function must be monitored for months after stopping.
- Psychiatric effects: Efavirenz has been linked to severe depression, suicidal ideation, paranoia, hallucinations, and psychosis. People with a prior psychiatric history face higher risk. Seek immediate medical attention for serious mood or behavior changes.
- Nervous system symptoms: Dizziness, trouble sleeping, impaired concentration, and abnormal dreams are very common, especially in the first 2–4 weeks. Bedtime dosing helps. Late-onset neurological problems (confusion, difficulty walking) have been reported months to years after starting treatment.
- Kidney damage: The tenofovir component can cause acute kidney failure and Fanconi syndrome (tubular injury). Avoid high-dose or frequent NSAIDs. Kidney labs should be checked before and during treatment.
- Bone density loss: Decreased bone mineral density has been observed, especially at the spine. Patients with fracture history or risk factors for bone loss should be evaluated.
- Embryo-fetal toxicity: Efavirenz can cause neural tube defects if taken in the first trimester. Women of childbearing potential must use effective contraception; note that hormonal methods alone may be less reliable with efavirenz.
- Lactic acidosis and liver enlargement with fat: A rare but potentially fatal complication linked to nucleoside antivirals; more common in women and people with obesity. Symptoms include unusual fatigue, abdominal pain, or difficulty breathing.
🔀What it interacts with▾
This medication interacts with a wide range of drugs — always tell your prescriber and pharmacist about everything you take. Key interactions include:
- Elbasvir/grazoprevir (Zepatier): Contraindicated — cannot be used together; this combination reduces hepatitis C treatment effectiveness
- Other HIV antiretrovirals: Should not be combined — this is already a complete HIV regimen
- Rifampin/rifabutin (TB antibiotics): Can lower efavirenz levels; dose adjustments may be needed
- Hepatitis C antivirals (simeprevir, boceprevir, sofosbuvir/velpatasvir, pibrentasvir/glecaprevir, others): Most are not recommended due to reduced effectiveness
- Hormonal contraceptives (pills and implants): Efavirenz can lower their levels — always add a barrier method like condoms
- Warfarin: Levels may rise or fall unpredictably — INR monitoring is essential
- Methadone: Levels can drop, potentially causing withdrawal — dose may need to be increased
- NSAIDs (like ibuprofen) at high or repeated doses: Increase risk of kidney damage when combined with tenofovir
- Cholesterol medications (statins like atorvastatin, pravastatin, simvastatin): Levels may be reduced; statin dosing may need adjustment
- Sorbitol-containing liquid medications: Can reduce lamivudine absorption — avoid when possible
- Drugs that prolong the QT interval (affect heart rhythm): Use caution; efavirenz itself can prolong the QT interval
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Hepatitis B coinfection: You must be tested for hepatitis B before starting — stopping this medication abruptly can cause a dangerous hepatitis B flare
- Kidney disease: Not recommended if your kidney function (creatinine clearance) is below 50 mL/min or if you are on hemodialysis
- Liver disease: Not recommended with moderate or severe liver impairment; use with caution in mild liver impairment
- Pregnancy: Efavirenz can cause birth defects, especially in the first trimester. Avoid pregnancy during treatment and for 12 weeks after stopping. Discuss reliable contraception with your doctor.
- Breastfeeding: Not recommended — HIV can be passed through breast milk
- Psychiatric history: History of depression, drug use, or mental health conditions increases the risk of serious psychiatric side effects from efavirenz
- Seizure history: Use with caution — efavirenz has been associated with convulsions
- Children: Only for patients who weigh at least 40 kg and can swallow a solid tablet
- Older adults: Pharmacokinetics of lamivudine and tenofovir have not been studied in patients over 65 — discuss with your prescriber
- Previous severe skin reaction to any component: Contraindicated if you've had Stevens-Johnson syndrome, erythema multiforme, or toxic skin eruptions from these drugs
🚑If you take too much▾
If too much is taken, watch for increased nervous system symptoms such as dizziness, involuntary muscle movements, or confusion — these have been reported when efavirenz was taken at higher-than-recommended doses. There is no specific antidote for any of the three components. Hemodialysis can remove some tenofovir but is not very effective for efavirenz or lamivudine. If an overdose is suspected, seek emergency medical care right away and call Poison Control.
📡Pharmacodynamics — effects in the body▾
Efavirenz affects the heart's electrical system in addition to fighting HIV — it can prolong the QTc interval (the time it takes for the heart to reset between beats), which is measured on an EKG. This effect is more pronounced in people with a certain genetic variation (CYP2B6 *6/*6) that causes higher efavirenz levels in the blood. Because of this, caution is needed when combining efavirenz with other medications that also affect heart rhythm.
🔬Pharmacokinetics — how your body processes it▾
Each of the three drugs is absorbed and cleared differently. Efavirenz peaks in the blood 3–5 hours after a dose and stays in the body for a long time — its half-life (the time for half the drug to leave your system) ranges from 40 to 76 hours, so it takes about 6–10 days to reach stable levels. It is heavily processed by liver enzymes (CYP3A and CYP2B6) and can speed up its own breakdown over time. Lamivudine is absorbed well and cleared mainly by the kidneys unchanged, with a half-life of 5–7 hours. Tenofovir also exits the body through the kidneys, with a half-life of about 17 hours. Because both lamivudine and tenofovir rely on the kidneys, reduced kidney function significantly increases their levels in the blood — which is why this medication is not recommended in people with impaired kidney function.
📦How to store it▾
Store at 20° to 25°C (68° to 77°F), excursions permitted between 15° to 30°C (59° to 86°F). Dispense in original container.
📄 Written from Efavirenz, Lamivudine, and Tenofovir’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
Supplements & herbs that interact with Efavirenz, Lamivudine, and Tenofovir
165 supplements and herbal products have documented interactions with Efavirenz, Lamivudine, and Tenofovir in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Major · 5
- Moderate · 120
- Minor · 40
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
Nutrient depletion considerations
Efavirenz, Lamivudine, and Tenofovir has been associated with lower levels of 1 nutrient in the clinical literature. This does not mean a deficiency will occur — it means these may be worth discussing with your pharmacist or healthcare provider, especially with long-term use.
Educational information from a licensed clinical database (Natural Medicines) — not medical advice. Do not start or stop medications or supplements without professional guidance.
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Efavirenz, Lamivudine, and Tenofovir — the kind of thing our pharmacy team would talk through with you at the counter.
Why do I have to take this on an empty stomach at bedtime? ▾
What should I do if I also have hepatitis B? ▾
Can this medication affect my mood or mental health? ▾
I'm on birth control — is that still going to work? ▾
Are there medications I absolutely cannot take with this? ▾
What side effects should I actually call my doctor about versus just wait out? ▾
Is Efavirenz, Lamivudine, and Tenofovir available over the counter? ▾
When was Efavirenz, Lamivudine, and Tenofovir first available? ▾
Who makes Efavirenz, Lamivudine, and Tenofovir? ▾
💬 Answers drafted from Efavirenz, Lamivudine, and Tenofovir’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Efavirenz, Lamivudine, and Tenofovir comes
Efavirenz, Lamivudine, and Tenofovir is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Tablet
How this form is used
- Symfi is indicated as a complete regimen for the treatment of HIV-1 infection in adults and pediatric patients weighing at least 40 kg
- Lamivudine and Tenofovir Disoproxil Fumarate (the combination tablet) is indicated as a complete regimen for the treatment of HIV-1 infection in adults and pediatric patients weighing at least 40 kg
- Symfi and Lamivudine and Tenofovir Disoproxil Fumarate tablets are each taken once daily by mouth on an empty stomach, preferably at bedtime
- Symfi and Lamivudine and Tenofovir Disoproxil Fumarate tablets should not be used in patients with a creatinine clearance below 50 mL/min or those on hemodialysis
- Symfi and Lamivudine and Tenofovir Disoproxil Fumarate tablets are not recommended for patients with moderate or severe liver impairment; use with caution in mild liver impairment
- Patients must be tested for hepatitis B infection before starting Symfi or the Lamivudine and Tenofovir Disoproxil Fumarate combination tablet
📊 Efavirenz, Lamivudine, and Tenofovir across the U.S. market
How Efavirenz, Lamivudine, and Tenofovir appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
📈 How widely Efavirenz, Lamivudine, and Tenofovir is used
A general measure of how commonly Efavirenz, Lamivudine, and Tenofovir is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Efavirenz, Lamivudine, and Tenofovir is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Efavirenz, Lamivudine, and Tenofovir prescribed? Of the 1,594 medications we measure, Efavirenz, Lamivudine, and Tenofovir ranks #1,480 by Medicaid prescriptions — more than 7% of them.
Utilization by Efavirenz, Lamivudine, and Tenofovir product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
efavirenz 400 MG / lamivudine 300 MG / tenofovir disoproxil fumarate 300 MG Oral Tablet Most dispensed
Summed across the 1 of 7 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2001424
efavirenz 600 MG / lamivudine 300 MG / tenofovir disoproxil fumarate 300 MG Oral Tablet
Summed across the 1 of 4 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 864661
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Efavirenz, Lamivudine, and Tenofovir, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 2 of 11 listed Efavirenz, Lamivudine, and Tenofovir NDCs with Medicaid activity.
🔍 Compare Efavirenz, Lamivudine, and Tenofovir products
A representative set of FDA-listed product records for Efavirenz, Lamivudine, and Tenofovir — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Tablet | ||||
| EFAVIRENZ 400 mg/1; LAMIVUDINE 300 mg/1; TENOFOVIR DISOPROXIL FUMARATE 300 mg | Oral | Laurus Labs Limited | ANDA | View NDC → |
| EFAVIRENZ 600 mg/1; LAMIVUDINE 300 mg/1; TENOFOVIR DISOPROXIL FUMARATE 300 mg | Oral | Laurus Labs Limited | ANDA | View NDC → |
| 400; 300; 300 mg/1; mg/1; mg | Oral | Laurus Labs Limited | ANDA | View NDC → |
| 600; 300; 300 mg/1; mg/1; mg | Oral | Laurus Labs Limited | ANDA | View NDC → |
| 400; 300; 300 mg/1; mg/1; mg | Oral | Mylan Specialty L.P. | NDA | View NDC → |
| 600; 300; 300 mg/1; mg/1; mg | Oral | Mylan Specialty L.P. | NDA | View NDC → |
| EFAVIRENZ 600 mg/1; LAMIVUDINE 300 mg/1; TENOFOVIR DISOPROXIL FUMARATE 300 mg | Oral | Viatris Specialty LLC | NDA | View NDC → |
Showing 7 of 7 products — FDA National Drug Code Directory. See every product, package size and price: browse all 7 Efavirenz, Lamivudine, and Tenofovir NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Efavirenz, Lamivudine, and Tenofovir — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Efavirenz, Lamivudine, and Tenofovir in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Efavirenz, Lamivudine, and Tenofovir went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
📦 Supply & shortage status
Whether Efavirenz, Lamivudine, and Tenofovir is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Efavirenz, Lamivudine, and Tenofovir belongs to the Human Immunodeficiency Virus 1 Non-Nucleoside Analog Reverse Transcriptase Inhibitor class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 3 FDA-filed SPL label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Mylan Specialty L.P. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.