Prescription & Treatment review

Dr. Sebastian Winckler

DrEd Medical Director

Mefloquine (sold as Lariam) is used in both the prevention and treatment of malaria, especially for certain strains of the parasite for which it’s known that other antimalarial drugs don’t work.

Mefloquine belongs to the antimalarial group of the quinolones, which work by killing the parasite causing malaria, therefore preventing any further infection from spreading in the body. This means that, in case of an infection, taking your Lariam treatment is time sensitive: the sooner you take it, the better.

If you’re going abroad soon and need a prevention treatment for malaria, you can buy Mefloquine online using our clinic. Complete the online consultation and get it delivered at home or to your preferred address.

DrEd, what should I know about Mefloquine ?

Mefloquine is the name of the active ingredient inside Lariam. It attacks the parasite causing malaria (known as Plasmodium) once it has entered your red blood cells, from where it multiplies and spreads to other red blood cells.

A malaria outbreak (high fever) happens when enough red blood cells have been infected so that they burst open altogether, thus releasing parasites into the bloodstream.

As with most other forms of prevention for malaria, the treatment with Mefloquine is to be started about two weeks before going to the malaria-affected area and then be continuously taken throughout the trip and for 2 to 4 weeks after leaving the area at risk – depending on your prescription.

Just like Doxycycline, the dose for the treatment of a malarial infection is at least 4 times that of the dose you take for prevention – i.e. 4-5 tablets instead of one (see below for treatment procedure).

Mefloquine is recommended in areas affected by a more aggressive form of the parasite known as falciparum malaria, that is resistant to chloroquine. Therefore make sure which treatment is recommended depending on your destination and on the reasons for your stay (e.g. high-risk backpacking vs low-risk 4* hotel).

It’s very important that you use the right medication and that you closely follow the prescription so that parasites don’t develop too much resistance to current antimalarials.

How to take Lariam - Mefloquine

Lariam tablets are to be taken whole (no chewing or crunching), preferably with a full glass of water – with or without food. If you are taking Lariam as a prevention measure for malaria, then you shouldn’t take it for more than 3 months. In any case, your doctor should prescribe you the right treatment plan if you are to stay more than 3 months, so make sure you tell him everything about your travel plans.

In the prevention of malaria, you must take one tablet of Lariam once a week on the same day, so as to ensure that you have the same amount of medicine in your body throughout the week.

When treating malaria on the other hand, you should first take 3 tablets at once, and then take one additional tablet about six to eight hours later. However, you must contact your doctor for advice on how to treat malaria in your specific case – and whether you need further medical attention.

If you forget to take Mefloquine, take your missed dose as soon as you remember it, unless it’s already time for your next dose (i.e. one week too late). Do not double dose to make up for a missed one.


There is a range of existing conditions and treatments that your doctor will need to know about before prescribing Mefloquine in order to make sure that he doesn’t put your health at risk. This information will help him (or her) decide whether Mefloquine is the right treatment for you or if you need specific treatment changes (e.g. dosage, combination with another antimalarial, etc.).

Your doctor will then need to know if you have any known allergy or hypersensitivity to drugs belonging to the group of quinolones (e.g. quinine). Also, if you have a history of psychiatric or convulsive disorders (e.g. depression, epilepsy) there might be some problems, as well as if you suffer from kidney or liver problems.

Do not take Lariam if you see that the packaging containing the tablets is damaged or if the expiry date has passed.

You must also contact your doctor immediately if you show the following signs of an allergic reaction, such as shortness of breath, swelling of the face, tongue or throat, and skin rash or hives.

Drug interactions & Dosing

Mefloquine can cause drug interactions with related antimalarials such as quinine and chloroquine, but also certain antihistamines, antidepressants and high blood pressure treatments.

Note that smoking and drinking may cause interactions so do talk with your doctor about whether it can be a problem for your prescription.

For malaria prevention, Lariam comes in the form of 250mg tablets to be taken once a week, one tablet at a time. However in the case of treatment of malaria, you can take Lariam either in one 1250mg tablet, or you can take 4 to 5 tablets (see “How to take Lariam”) – depending on what’s available near you and on what your doctor says.

Mefloquine – Side-effects

The most common side-effects of mefloquine include:

- Nausea
- Vomiting
- Diarrhoea
- Dizziness
- Headache
- Drowsiness, sleepiness or insomnia
- Abnormal dreams
- Blurred vision

Less common side-effects of Lariam include:

- Vision problems
- Palpitations (fast heart beat)
- Mood swings
- Confusion or anxiety
- Itching and/or skin rash
- Fever and/or chills

You must seek immediate medical help – either going to the hospital or contacting your doctor – if you experience a seizure, severe change in mood, chest pain, yellow-ish eyes or severe fatigue or fever symptoms (it may be a sign of malarial infection).

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