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mefloquine

Generic Name: mefloquine (MEH flow quinn)
Brand Names: Lariam

What is mefloquine?

Mefloquine is an antimalarial drug. The exact way that mefloquine works is unknown.

Mefloquine is used in the treatment and prevention of malaria.

Mefloquine may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about mefloquine?

In some cases, serious mental side effects have occurred in people taking mefloquine. Stop taking mefloquine and seek medical attention immediately if unexplained signs of anxiety, depression, restlessness, feelings that people are against you, hallucinations (seeing or hearing things that are not there, for example), psychotic behavior, thoughts of suicide, or confusion occur. However, it is important to continue to take a medicine for protection from malaria when traveling to a malaria area. A healthcare provider may need to prescribe a different medication. Use caution when driving or performing other hazardous activities until you know how this medication affects you. Mefloquine may cause dizziness, restlessness, or confusion during therapy and for several weeks after treatment has ended.

Mefloquine is not 100% effective for the prevention of malaria. Protective clothing, insect repellents, and bednets are important components of malaria prophylaxis. Seek medical attention for any illness with fever that occurs after return from a malarious area and inform your doctor that you may have been exposed to malaria.

What should I discuss with my healthcare provider before taking mefloquine?

Do not take mefloquine without first talking to your doctor if you have a history of depression, an anxiety disorder, psychosis, schizophrenia, another major psychiatric disorder, or seizures.

Before taking mefloquine, tell your doctor if you have

liver disease;
an irregular heartbeat or heart disease; or
an allergy to quinine or quinidine.

You may not be able to take mefloquine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

Mefloquine is in the FDA pregnancy category C. This means that it is not known whether it will be harmful to an unborn baby. Animal studies have shown that it may be dangerous. It is recommended that a reliable birth control be used during treatment with mefloquine. Do not take this medication without first talking to your doctor if you are pregnant or could become pregnant during treatment. Mefloquine passes into breast milk and may affect a nursing baby. Do not take mefloquine without first talking to your doctor if you are breast-feeding a baby.

How should I take mefloquine?

Take mefloquine exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass, at least 8 ounces (240 mL) of water. Take mefloquine immediately after a meal.

For children or those who have difficulty swallowing, mefloquine can be crushed and mixed with water or sugar water. Talk to your healthcare provider if swallowing the tablets is difficult.

If vomiting occurs within 30 minutes of taking a dose of mefloquine, an additional dose should be taken. If vomiting occurs within 30 to 60 minutes of taking a dose, an additional half-dose should be taken unless otherwise directed by your doctor.

For malaria prevention, you may need to take mefloquine before you travel, while you are in a malaria area, and for several weeks after you leave the area. Your healthcare provider will give you detailed instructions. For the treatment of malaria, directions for taking the medication may be different.

In some cases, serious mental side effects have occurred in people taking mefloquine. Stop taking mefloquine and seek medical attention immediately if unexplained signs of anxiety, depression, restlessness, feelings that people are against you, hallucinations (seeing or hearing things that are not there, for example), psychotic behavior, thoughts of suicide, or confusion occur. If you stop taking mefloquine, leave the malaria area unless you are able to contact a health care provider or have access to another medication to protect against malaria. You should be aware that leaving the malaria area does not protect you from getting malaria. You still need to take a medicine to protect against malaria.

Tell your healthcare providers that you are taking mefloquine before taking any new medications. Also, tell you healthcare providers if you have recently finished taking mefloquine before taking any new medications.

Store mefloquine at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and only take the next regularly scheduled dose. Do not take a double dose of the medication.

What happens if I overdose?

Seek emergency medical attention if an overdose is suspected.

Symptoms of a mefloquine overdose may be similar to side effects of the medication, although often more severe.

What should I avoid while taking mefloquine?

Use caution when driving or performing other hazardous activities until you know how this medication affects you. Mefloquine may cause dizziness, restlessness, or confusion during therapy and for several weeks after therapy is stopped.

Immunizations that use live attenuated (weakened) strains of a virus or bacteria should be completed at least 3 days before the first dose of mefloquine to ensure an adequate effect of the immunization.

Mefloquine side effects

Mefloquine may affect your liver and your eyes if you take it for a long time. Ask your healthcare provider to tell you if you should have your eyes and liver checked while taking mefloquine.

If you experience any of the following serious side effects, seek emergency medical attention:

an allergic reaction (swelling of the lips, face, or tongue; shortness of breath; difficulty breathing; or closing of the throat);
seizures; or
irregular heartbeats.

Other, less serious side effects may be more likely to occur. Continue to take mefloquine and talk to your doctor if you experience

nausea, vomiting, diarrhea, or loss of appetite;
chills or fever;
muscle aches or weakness;
ringing in the ears;
a rash or itching;
blurred vision;
insomnia or abnormal dreams;
headache; or
dizziness or drowsiness.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Mefloquine Dosing Information

Usual Adult Dose for Malaria:

Mild to moderate infections due to Plasmodium vivax or mefloquine-susceptible P falciparum: 1250 mg (5 tablets) orally as a single dose; alternatively, a regimen of 750 mg initially, followed by 500 mg 12 hours later has been used

The drug should not be taken on an empty stomach and should be administered with at least 8 oz (240 mL) of water.

In addition, primaquine should be given to patients with P vivax infections to eliminate hepatic phase parasites.

Patients with severe or life-threatening malaria infections should be treated with IV antimalarials. Mefloquine may be used to complete the course of therapy after IV therapy has been completed.

Usual Adult Dose for Malaria Prophylaxis:

250 mg orally once a week on the same day, preferably after the main meal

Administration should begin 1 week before departure and continued for 4 weeks after returning. The dose should not be taken on an empty stomach and should be administered with at least 8 oz (240 mL) of water.

Patients should be advised that additional precautions are necessary (i.e., protective clothing, insect repellents, and bednets), and that they should seek medical attention if they develop a febrile illness after returning from an endemic area.

Usual Pediatric Dose for Malaria:

Mild to moderate infections due to mefloquine-susceptible P falciparum:
20 kg or more: 20 to 25 mg/kg orally once; alternatively, the total dose may be split into 2 doses given 6 to 8 hours apart, to reduce the severity of side effects

The dose should not be taken on an empty stomach and should be administered with plenty of water.

A second full dose should be given if the patient vomits less than 30 minutes after taking mefloquine. An additional half-dose should be given if the patient vomits 30 to 60 minutes after taking mefloquine.

Usual Pediatric Dose for Malaria Prophylaxis:

The recommended prophylactic dose is approximately 5 mg/kg orally once a week on the same day, starting 1 week before departure and continuing for 4 weeks after return. The dose should not be taken on an empty stomach and should be administered with plenty of water.

20 to 30 kg: 125 mg (1/2 tablet) orally once a week
30 to 45 kg: 187.5 mg (3/4 tablet) orally once a week
Greater than 45 kg: 250 mg (1 tablet) orally once a week

Experience with mefloquine in pediatric patients less than 20 kg is limited.

Patients should be advised that additional precautions are necessary (i.e., protective clothing, insect repellents, and bednets), and that they should seek medical attention if they develop a febrile illness after returning from an endemic area.

What other drugs will affect mefloquine?

Do not take mefloquine with any of the following medications without first talking to your doctor:

a heart medicine in the class called beta-blockers, such as propranolol (Inderal), metoprolol (Lopressor), acebutolol (Sectral), betaxolol (Kerlone), carteolol (Cartrol), carvedilol (Coreg), labetalol (Normodyne, Trandate), nadolol (Corgard), pindolol (Visken), timolol (Blocadren), and others;
any medicine used to treat seizures;
chloroquine (Aralen); or
quinidine (Cardioquin, Quinaglute, Quinora, Quinidex) or quinine (Quinamm).

Taking mefloquine may be dangerous if you are taking any of the medications listed above.

Immunizations that use live attenuated (weakened) strains of bacteria should be completed at least 3 days before the first dose of mefloquine to ensure an adequate effect of the immunization.

Drugs other than those listed here may also interact with mefloquine. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

Where can I get more information?

Your pharmacist can provide more information about mefloquine.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.