Mefloquine (By mouth)


Mefloquine (ME-floe-kwin)
Prevents and treats malaria.

Brand Name(s)

There may be other brand names for this medicine.


When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to mefloquine or similar medicines (such as quinine or quinidine), or if you have a history of seizures (convulsions). Do not use this medicine if you have emotional or mental problems, such as anxiety, psychosis, schizophrenia, or depression.

How to Use This Medicine

  • Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
  • This medicine comes with a medication guide and an information wallet card. Read and follow the instructions carefully. Talk with your doctor if you have any questions.
  • It is best to take this medicine with food or milk. Drink at least 8 ounces (1 cup) of water with each dose of medicine. You may crush the medicine and mix it with water or sugar water to give the medicine to a young child.
  • If you are using this medicine to prevent malaria, you may need to start using it at least 1 week before you travel outside the U.S. You may also need to keep using this medicine for 4 weeks after you get home. Ask your doctor about your schedule. It is best to always use your medicine on the same day of the week.
  • Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.
If a dose is missed:
  • If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine after you have finished your treatment. You will also need to throw away old medicine after the expiration date has passed.
  • Keep all medicine away from children and never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
  • Make sure your doctor knows if you are also using chloroquine (Aralen®), rifampin (Rifadin®, Rimactane®), medicine for seizures (such as carbamazepine, phenobarbital, phenytoin, valproic acid, Depakote®, Dilantin®, Keppra?, Luminal®, or Tegretol®), a blood thinner (such as warfarin, Coumadin®), or a diabetes medicine (such as glyburide, Actos?, Avandia®, Glucotrol®, or Glucophage®).
  • Make sure your doctor knows if you are also using medicine for heart rhythm problems (such as amiodarone, disopyramide, dofetilide, sotalol, Cordarone®, Betapace®, Norpace®, or Tikosyn®), certain blood pressure medicine (such as atenolol, metoprolol, propranolol, verapamil, Lotrel®, Norvasc®, or Toprol®), medicine for depression (such as amitriptyline, fluoxetine, nortriptyline, Elavil®, Pamelor®, Prozac®, Sarafem®, or Vivactil®), or a phenothiazine medicine (such as prochlorperazine, Compazine®, Mellaril®, Phenergan®, Thorazine®, or Trilafon®).
  • Do not take halofantrine (Halfan®) or ketoconazole (Nizoral®) with mefloquine or within 15 weeks after the last dose of this medicine, unless your doctor tells you otherwise.
  • If you are using this medicine to prevent malaria, first find out if you also need a typhoid vaccine. You may need to have the typhoid vaccine at least 3 days before you start using mefloquine.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding, or if you have liver disease, blood clotting problems, epilepsy, heart disease, heart block, heart rhythm problems (such as prolonged QT interval), slow heartbeat, or a history of depression.
  • Use birth control pills while you are taking mefloquine and for 3 months after you stop treatment with this medicine. If you think you have become pregnant while using this medicine, tell your doctor right away.
  • You may still get malaria even while using this medicine. If you get sick or have a fever, call your doctor. To help prevent malaria, you can also use bug spray, wear protective clothing, and keep a mosquito net around your bed.
  • A child may vomit after taking this medicine. Ask your doctor what to do if this happens.
  • This medicine may make you dizzy, drowsy, or lose your balance. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
  • Check with your doctor immediately if blurred vision, difficulty in reading, or any other change in vision occurs during or after treatment. Your doctor may want you to have your eyes checked by an ophthalmologist (eye doctor).
  • This medicine can cause changes in heart rhythms, such as a condition called QT prolongation. It may change the way your heart beats and cause fainting or serious side effects in some patients. Call your doctor right away if you have any symptoms of heart rhythm problems, such as fast, pounding, or irregular heartbeats.
  • Your doctor will need to check your progress at regular visits while you are using this medicine. Be sure to keep all appointments. Blood tests and eye exams may be needed to check for unwanted effects.
  • If your symptoms do not improve or if they get worse, call your doctor.
  • Some of the side effects listed below may happen after you stop using this medicine. Call your doctor if you have side effects, even if you are no longer using this medicine.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:
  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
  • Blistering, peeling, or red skin rash.
  • Dizziness or fainting.
  • Fast, slow, pounding, or uneven heartbeat
  • Feeling confused, depressed, nervous, or restless.
  • Fever, chills, cough, sore throat, and body aches.
  • Feeling of constant movement of self or surroundings.
  • Seeing or hearing unusual things.
  • Seizures.
  • Unusual behavior or thoughts of hurting or killing others or oneself.
  • Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
  • Headache.
  • Nausea, vomiting, diarrhea, loss of appetite, or stomach pain.
  • Ringing in your ears.
  • Skin rash.
  • Trouble sleeping.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
Review Date: 2011-02-04 Reviewed By: Keywords: ,
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