Active Ingredient

Mefloquine

Mefloquine is an antimalarial medication used to prevent and treat malaria, a disease caused by parasites transmitted through mosquito bites. It is particularly useful in regions where malaria is resistant to other drugs.

This medication is usually taken before entering and during a stay in areas where malaria is common.

Written By Douglas C. Goldberg, MD

Reviewed By Philip Schein, MD

Last Updated 28 Nov 2025

Available Mefloquine Brands

Lariam

Strengths 250mg

Mefloquine Uses

Mefloquine is primarily used for the prevention and treatment of malaria. It is effective in areas with drug-resistant malaria strains.

Prevention of malaria in travelers.
Treatment of acute malaria infections.
Part of combination therapy for resistant malaria.

How Mefloquine Works

Mefloquine works by interfering with the growth of parasites in the red blood cells of the human body. It disrupts the parasite’s ability to multiply and survive.

As an antimalarial agent, it targets the parasite causing malaria, helping to clear the infection and prevent its spread.

Common side effects of Mefloquine

Not everyone experiences side effects with Mefloquine, and many are mild and temporary. However, it’s important to be aware of them.

Nausea
Dizziness
Headache
Difficulty sleeping
Strange dreams
Abdominal pain
Diarrhea

If you experience serious or persistent symptoms, contact your doctor.

Take Mefloquine with food to help reduce stomach upset.
Avoid consuming large amounts of alcohol while taking this medication.
Inform your doctor about any other medications you are taking to avoid potential interactions.
Do not use this medication if you have a history of mental health issues without consulting your doctor.
Monitor for any unusual changes in mood or behavior and report them to your healthcare provider.

Always consult your doctor for personalized medical advice.

Frequently Asked Questions

How long does it take for Mefloquine to start working?

Mefloquine starts working soon after you take it, but it is important to follow the prescribed schedule for prevention or treatment.

Can I drink alcohol while taking Mefloquine?

It is advisable to avoid large amounts of alcohol while taking Mefloquine as it may increase the risk of side effects.

What should I do if I miss a dose?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule.

Is Mefloquine safe for long-term use?

Mefloquine is generally used for short-term prevention or treatment of malaria. Long-term use should be monitored by a healthcare professional.

What should I avoid while taking Mefloquine?

Avoid activities requiring alertness, such as driving, if you experience dizziness or other side effects. Also, inform your doctor about any other medications you are taking.