Methamphetamine

Generic name: Pronounced as (meth'' am fet' a meen)
Brand names
  • Desoxyn®
Click on drug name to hear pronunciation

Medical Content Reviewed By HelloPharmacist Staff

Last Revised - 06/15/2017

Methamphetamine can be habit-forming. Do not take a larger dose, take it more often, or take it for a longer time than prescribed by your doctor. Methamphetamine should only be taken for a short period (e.g., a few weeks) when used for weight loss. However, if you take too much methamphetamine you may find that the medication no longer controls your symptoms, you may feel a need to take large amounts of the medication, and you may experience symptoms such as rash, difficulty falling asleep or staying asleep, irritability, hyperactivity, and unusual changes in your personality or behavior. Overusing methamphetamine may also cause serious heart problems or sudden death.

Tell your doctor if you or anyone in your family drinks or has ever drunk large amounts of alcohol, uses or has ever used street drugs, or has overused prescription medications. Your doctor will probably not prescribe methamphetamine for you.

Do not stop taking methamphetamine without talking to your doctor, especially if you have overused the medication. Your doctor will probably decrease your dose gradually and monitor you carefully during this time. You may experience depression and extreme tiredness if you suddenly stop taking methamphetamine after overusing it.

Do not sell, give away, or let anyone else take your medication. Selling or giving away methamphetamine is against the law and may harm others. Store methamphetamine in a safe place so that no one else can take it accidentally or on purpose. Keep track of how many tablets are left so you will know if any are missing.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with methamphetamine and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.

Methamphetamine is used as part of a treatment program to control symptoms of attention deficit hyperactivity disorder (ADHD; more difficulty focusing, controlling actions, and remaining still or quiet than other people who are the same age) in children. Methamphetamine is also used for a limited period of time (a few weeks) along with a reduced calorie diet and an exercise plan for weight loss in obese people unable to lose weight. Methamphetamine is in a class of medications called central nervous system stimulants. It works by changing the amounts of certain natural substances in the brain.

Methamphetamine comes as a tablet to take by mouth. If your child is taking methamphetamine for ADHD, it is usually taken one or two times daily. If you are taking methamphetamine for weight management, it is usually taken 30 minutes before meal(s). This medication may cause difficulty falling asleep or staying asleep if it is taken in the evening. Take methamphetamine at around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take methamphetamine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

If your child is taking methamphetamine for ADHD, the doctor will probably start the child on a low dose and gradually increase the dose, not more often than once every week. The doctor may stop methamphetamine treatment from time to time to see if the medication is still needed. Follow these directions carefully.

If you are taking methamphetamine to lose weight, the doctor will maintain you on the lowest dose possible. Tolerance to the weight loss effect may develop within a few weeks, making this medication less effective. When this occurs, the doctor may stop the medication.

Methamphetamine helps to control ADHD but does not cure this condition. Continue to take methamphetamine even if you feel well. Do not stop taking methamphetamine without talking to your doctor.

Methamphetamine should not be used to treat excessive tiredness.

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

Before taking methamphetamine,

  • tell your doctor and pharmacist if you are allergic to methamphetamine, other stimulant medications such as amphetamine, benzphetamine, dextroamphetamine (Dexedrine, in Adderall), lisdexamfetamine (Vyvanse), any other medications, or any of the ingredients in methamphetamine tablets. Ask your pharmacist for a list of the ingredients.

  • tell your doctor if you are taking the following medications or have stopped taking them in the past 14 days: monoamine oxidase (MAO) inhibitors including isocarboxazid (Marplan), linezolid (Zyvox), methylene blue, phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate). If you stop taking methamphetamine, you should wait at least 14 days before you start to take an MAO inhibitor.

  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, and herbal products you are taking. Be sure to mention any of the following: acetazolamide (Diamox); ammonium chloride; ascorbic acid (Vitamin C); fentanyl (Actiq, Duragesic, Subsys, others); insulin; lithium (Lithobid); medications for high blood pressure; methenamine (Hiprex, Urex); medications for migraine headaches such as almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt), sumatriptan (Imitrex, in Treximet), and zolmitriptan (Zomig); omeprazole (Prilosec); phenothiazine medications for mental illness or nausea such as chlorpromazine, fluphenazine, prochlorperazine (Compro, Procomp), promethazine (Promethegan), thioridazine, or trifluoperazine; quinidine (in Nuedexta); reserpine; ritonavir (Norvir, in Kaletra); certain medications for seizures such as ethosuximide (Zarontin), phenobarbital, and phenytoin (Dilantin, Phenytek); selective serotonin-reuptake inhibitors such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem, in Symbyax), fluvoxamine (Luvox), paroxetine (Brisdelle, Prozac, Pexeva), and sertraline (Zoloft); serotonin and norepinephrine reuptake inhibitors such as desvenlafaxine (Khedezla, Pristiq), duloxetine (Cymbalta), milnacipran (Savella), and venlafaxine (Effexor); sodium bicarbonate (Arm and Hammer Baking Soda, Soda Mint); sodium phosphate; tramadol; or tricyclic antidepressants ('mood elevators') such as desipramine (Norpramin) or protriptyline (Vivactil). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

  • tell your doctor what herbal products you are taking, especially St. John's wort and tryptophan or nutritional supplements you are taking including glutamic acid (L-glutamine).

  • tell your doctor if you have glaucoma (increased pressure in the eye that may cause vision loss), hypertension (high blood pressure), hyperthyroidism (condition in which there is too much thyroid hormone in the body), feelings of anxiety, tension, or agitation, or heart or blood vessel disease. Your doctor will probably tell you not to take methamphetamine.

  • tell your doctor if anyone in your family has or has ever had an irregular heartbeat or has died suddenly. Also tell your doctor if you have recently had a heart attack, and if you have or have ever had a heart defect, an irregular heartbeat, or other heart problems. Your doctor will examine you to see if your heart and blood vessels are healthy. Your doctor will probably tell you not to take methamphetamine if you have a heart condition or if there is a high risk that you may develop a heart condition.

  • tell your doctor if you or anyone in your family has or has ever had depression, bipolar disorder (mood that changes from depressed to abnormally excited), or mania (frenzied, abnormally excited mood), facial or motor tics (repeated uncontrollable movements), verbal tics (repetition of sounds or words that is hard to control) or Tourette's syndrome (a condition characterized by the need to perform repeated motions or to repeat sounds or words), or has thought about or attempted suicide. Also tell your doctor if you have or have ever had mental illness, seizures, diabetes, or an abnormal electroencephalogram (EEG; test that measures electrical activity in the brain). If your child is taking methamphetamine to treat ADHD, tell your child's doctor if your child has recently experienced unusual stress.

  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking methamphetamine, call your doctor. Do not breastfeed while taking methamphetamine.

  • you should know that methamphetamine may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.

  • you should know that methamphetamine should be used as part of a total treatment program for ADHD, which may include counseling and special education. Make sure to follow all of your doctor's and/or therapist's instructions.

  • you should know that methamphetamine may cause sudden death in children and teenagers, especially children and teenagers who have heart defects or serious heart problems. This medication also may cause sudden death, heart attack, or stroke in adults, especially adults with heart defects or serious heart problems. Call your or your child's doctor right away if you or your child has any signs of heart problems while taking this medication including: chest pain, shortness of breath, or fainting.

Unless your doctor tells you otherwise, continue your normal diet.

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.

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

    • restlessness

    • upset stomach

    • constipation

    • dry mouth

    • unpleasant taste

    • headache

    • weight loss

    • loss of appetite

    • itching

    • changes in sex drive or ability

    • difficulty falling asleep or staying asleep

  • Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, stop taking methamphetamine and call your doctor immediately or get emergency medical treatment:

    • fast or pounding heartbeat

    • uncontrollable shaking of a part of your body

    • excessive tiredness

    • slow or difficult speech

    • seizures

    • motor or verbal tics

    • believing things that are not true

    • feeling unusually suspicious of others

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

    • agitation, hallucinations (seeing things or hearing voices that do not exist), fever, sweating, confusion, fast heartbeat, shivering, severe muscle stiffness or twitching, loss of coordination, nausea, vomiting, or diarrhea

    • mania (frenzied or abnormally excited mood)

    • aggressive or hostile behavior

    • changes in vision or blurred vision

    • paleness or blue color of fingers or toes

    • pain, burning, or tingling in the hands or feet

    • unexplained wounds appearing on fingers or toes

  • Methamphetamine may slow children's growth or weight gain. Your child's doctor will watch his or her growth carefully. Talk to your child's doctor if you have concerns about your child's growth or weight gain while he or she is taking this medication. Talk to your child's doctor about the risks of giving methamphetamine to your child.

  • Methamphetamine 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 light, excess heat and moisture (not in the bathroom).

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.

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

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 the following:

  • fever

  • restlessness

  • uncontrollable shaking of a part of your body

  • confusion

  • fast breathing

  • aggressive behavior

  • tiredness

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

  • panic

  • depression

  • irregular heartbeat

  • vomiting

  • nausea

  • diarrhea

  • stomach cramps

  • seizures

  • coma (loss of consciousness for a period of time)

Keep all appointments with your doctor.

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

This prescription is not refillable. Be sure to schedule appointments with your doctor on a regular basis so that you do not run out of medication.

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.

Content provided by: AHFS® Patient Medication Information™. © Copyright, 2021. The American Society of Health-System Pharmacists