Mefloquine

This information from Lexicomp^® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

What is this drug used for?

• It is used to treat or prevent malaria.

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have ever had any of these health problems: Anxiety, depression, psychosis, schizophrenia, or any other mental or mood problem.
• If you have ever had seizures.
• If you are taking any of these drugs: Chloroquine, quinidine, or quinine.
• If you are taking any of these drugs: Halofantrine or ketoconazole. Do not take these drugs within 15 weeks of your last dose of this drug.
• If you have recently had a live vaccine.

This is not a list of all drugs or health problems that interact with this drug.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

For all uses of this drug:

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
• Have patient safety card with you at all times.
• Have your blood work checked if you are on this drug for a long time. Talk with your doctor.
• Have an eye exam as you have been told by your doctor.
• This drug may raise the chance of seizures in some people, including people who have had seizures in the past. Talk to your doctor to see if you have a greater chance of seizures while taking this drug.
• If you may become pregnant, you must use birth control while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
• Tell your doctor if you are breast-feeding or plan to breast-feed. This drug passes into breast milk and may harm your baby.

Preventing malaria:

• Other measures are needed along with this drug including using screens, bed netting, insect repellent (10% to 35% DEET), and permethrin spray on clothing and nets. Avoid spraying most insect repellents on children. Lower evening and night-time outdoor activity.
• If you have a fever while in or after leaving a malaria area, call your doctor right away.
• If you are pregnant and traveling to a malaria infested place, talk to your doctor about the risks first.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Chest pain or pressure or passing out.
• Fast, slow, or abnormal heartbeat.
• Change in eyesight, eye pain, or severe eye irritation.
• Trouble sleeping.
• Some people taking this drug have committed suicide. It is not known if this drug was the reason for the suicides. Tell your doctor if you have thoughts of suicide.
• Blood cell problems have happened, like aplastic anemia and a type of low white blood cell count. Tell your doctor right away if you feel very tired or weak or have a fever, chills, shortness of breath, any unexplained bruising or bleeding, or purple “splotches” on your skin.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Headache.
• Diarrhea, stomach pain, upset stomach, throwing up, or decreased appetite.
• Muscle pain.
• Feeling tired or weak.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

For all uses of this drug:

• Take this drug with the largest meal of the day.
• Do not take on an empty stomach.
• Take with a full glass of water.
• Tablet can be crushed and mixed with water, milk, or other liquid.
• Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
• Talk with your doctor to find out what to do if you throw up after taking a dose of this drug.

Preventing malaria:

• If using to prevent malaria, start this drug before traveling to the high risk place as you have been told by the doctor.

What do I do if I miss a dose?

Treating malaria:

• Most of the time, 1 dose of this drug is needed. If you miss the dose, take it as soon as you think about it with food. If you need to take more than 1 dose of this drug, follow what your doctor has told you to do.

Preventing malaria:

• Take a missed dose as soon as you think about it.
• If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.
• If you miss a dose before leaving for your trip, call your doctor to find out what to do.

How do I store and/or throw out this drug?

• Store at room temperature in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• This drug comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this drug is refilled. If you have any questions about this drug, please talk with the doctor, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2023-03-28

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