Lariam is a medication used to both prevent and treat malaria. Malaria is a serious disease that is transmitted via mosquitoes in certain countries. Travellers to these areas, which include sub-Saharan Africa, South America, and many parts of Asia, are advised to take anti-malarial medication such as Lariam to prevent the illness occurring.
Lariam is usually recommended when travelling to an area where the pathogen has become resistant to other, more commonly prescribed, anti-malarial medications.
- Lariam is used to prevent and treat malaria
- It contains the active ingredient mefloquine
- Mefloquine works by killing the parasites that enter your body via the bite of an infected mosquito
- It is also important to protect yourself against mosquito bites by wearing DEET insect repellent, using nets to sleep under, and covering your skin with clothing at dusk and dawn
- It is important to read the patient leaflet for a full list of side effects and cautions.
How Does Lariam Work?
Malaria is a serious disease that can be fatal if left untreated. It is caused by a parasite that is carried by mosquitoes in certain parts of the world. If an infected mosquito bites you, the parasite (most commonly P. falciparum) can be transferred into your blood stream, infecting you with malaria.
Lariam works by killing P. falciparum. This means that even if you are bitten by an infected mosquito, you will be protected against malaria. When taken correctly, Lariam prevents around 90% of malaria infections.
As Lariam is not 100% effective, it is also important to protect yourself against being bitten by mosquitoes even when you are taking an anti-malarial medication. This includes sleeping beneath a mosquito net, spraying DEET on exposed skin and clothing, using insecticides in your room and covering your skin with loose clothing.
Lariam is also sometimes used to treat someone who has developed a malaria infection.
How is Lariam Taken?
Lariam is a tablet that is taken once a week. It should not be taken on an empty stomach as this may cause digestive side effects. The tablet is also better absorbed when you take it with food. You should take Lariam on the same day each week with a main meal.
Dosage of Lariam
Each tablet of Lariam contains 250mg of mefloquine. For adults, it is usually prescribed as follows:
- Take 1 tablet 10 days before departure to an endemic area
- Take 1 tablet 1 week later (3 days before departure)
- Continue taking 1 tablet each week on the same day
- Continue taking 1 tablet each week for a further 4 weeks after leaving the malarious area.
The minimum treatment period is 6 weeks, and the maximum duration of treatment is 12 months.
If you are being treated for malaria infection, your dosage will be different, and so you must follow your prescriber’s instructions.
Are there any Side Effects?
Like all medications, Lariam can have some side effects. The most common side effects include:
- Nausea and vomiting (feeling sick and being sick)
- Loss of balance
- Abnormal dreams
- Difficulty sleeping
- Abdominal pain
These side effects are likely to settle down, but if they persist or become troublesome you should speak to your doctor for further advice.
Taking Lariam can sometimes lead to the side effects of anxiety and depression, which can become severe. If you notice even a mild change in your mood, you must speak to your doctor who will assess whether a different anti-malarial medication may be more suitable.
Rarely, Lariam can cause serious side effects including pain or burning sensations, muscle weakness, changes to eyesight, yellowing of the skin or eyes, breathlessness, or cough. If any of these side effects occur, you should speak to a doctor straight away.
Serious allergic reactions happen very rarely. If you have a severe allergic reaction (anaphylaxis) including breathlessness, lip swelling or tongue swelling, call 999 immediately.
Lariam may not be suitable for everyone. You should tell your prescriber if you:
- Have hypersensitivity to Lariam, mefloquine, quinine or quinidine
- Have depression, or any history of mental health problems
- Have ever had Blackwater fever
- Have severe liver disease
- Have an abnormal heart rhythm
- Have epilepsy
- Have galactose intolerance
- Are pregnant, trying to conceive, or breastfeeding – Lariam is usually deemed unsuitable at these times and another anti-malarial should be considered.
Some medications can interact with Lariam. You may be advised that Lariam will not suit you if you already take:
- Halofantrine (or if you have taken it in the last 15 weeks)
- Ketoconazole (or if you have taken it in the last 15 weeks)
- Medications for epilepsy or seizures
- Medications for an abnormal heart rhythm
- Tricyclic or SSRI antidepressants
- Antipsychotic medications