The use of mefloquine can cause side effects in some people.
Very common side effects
Common side effects
- problems with your vision
- loss of balance or vertigo
- feeling sick (nausea)
- stomach ache, nausea and vomiting
- diarrhoea, stomach ache
Other side effects (frequency not known)
- lack of appetite
- difficulty talking
- blurred vision
- ringing in the ears or other changes to your hearing
- changes to your heart rate or blood pressure level
- hot flushes, breathlessness
- muscle and joint pains
- hair loss
- psychological disturbance such as anxiety, paranoia, depression, hallucinations: see below
For a full list of all possible side effects, read the patient leaflet supplied with your mefloquine tablets.
Stop taking mefloquine and speak to you doctor immediately if you experience:
- allergic reaction (may cause symptoms such as difficulty breathing, swelling, rash and itching)
- changes in the texture of your skin, eyes and mouth
- fever, chills, cough, chest pain
- tender or enlarged liver, jaundice or abnormal blood test results indicating a liver problem
- dark urine, light stools, generalised itching
- feeling weak
- numbness, pins and needles, shaking of hands or fingers
- mouth ulcers, bruises or nosebleeds
- vaginal bleeding or bleeding in the stomach
- mood changes or psychiatric side effects (see below)
Does mefloquine cause psychiatric side effects?
Mefloquine can cause psychiatric side effects in some people. It is important that you speak to a doctor if you notice any changes in your mood while taking the medication.
Stop taking mefloquine and seek medical help immediately if you experience any of the following:
- panic attacks
- suicidal thoughts or attempted suicide
- risk taking behaviour
- losing touch with reality
- feelings of mistrust towards others
- unusual behaviour or mood changes
- unusual aggression and anger
- difficulty concentrating
Driving and operating machinery
Mefloquine can have an impact on your ability to drive and operate machinery. It is therefore not recommended that you take it if you will be piloting an aircraft. Mefloquine tablets can cause dizziness, psychiatric side effects as well as loss of balance. Scuba diving is therefore unsafe if you are taking mefloquine. Do not perform any tasks which require concentration and coordination if you notice any of these side effects.
Mefloquine tablets can interact with other medications. make sure you mention all medications you are currently taking or have recently taken to your doctor when you request your prescription.
- blood pressure medication
- medications to treat heart problems
- medication for psychiatric problems, for example antidepressants
- medications to treat epilepsy or seizures
- the painkiller tramadol
- medications to treat blood clotting disorders or diabetes
- efavirenz (used to treat HIV infections)
If you require an oral typhoid vaccination before travelling you must ensure that you get vaccinated at least three days before you need to start taking mefloquine (as mefloquine can stop the vaccine from working).
For a detailed list of possible drug interactions, read the patient leaflet.
Back to top