Flunarizine
1 medicine
Flunarizine is a calcium channel blocker used to prevent migraine and treat vertigo. With long-term use it can cause depression or parkinsonism-like movement problems, especially in older adults, so treatment is reviewed regularly and stopped if these appear.
Key facts
- Flunarizine blocks calcium channels in blood vessels and nerve cells in the brain and inner ear, which calms the overactivity behind migraine and some types of vertigo.
- It is taken once daily, usually at night, because it can make you drowsy. Migraine prevention can take several weeks to show its full effect.
- With continued use flunarizine can cause depression or parkinsonism-like symptoms (slowness, stiffness, tremor), particularly in older adults. Treatment is usually reviewed after a few months and stopped if either of these develops.
- Seek urgent care for new or worsening low mood, unusual muscle stiffness or tremor, or thoughts of self-harm.
What flunarizine treats
Flunarizine is used to prevent recurrent migraine attacks and to treat vertigo caused by problems in the inner ear's balance system. It does not stop a migraine that has already started and is not a painkiller.
How flunarizine works
Flunarizine blocks calcium from entering certain blood vessel and nerve cells in the brain and inner ear. This steadies blood vessels that would otherwise narrow and widen during a migraine, and calms overactive nerve signals that contribute to vertigo, reducing how often attacks occur.
Before you take it
- Do not take flunarizine if you have current depression, a history of parkinsonism or other movement disorders, or a known allergy to it.
- Tell your prescriber about liver disease, since the drug is broken down there, and about any other medicines that cause drowsiness, since effects can add up.
- Flunarizine is usually avoided in pregnancy and breastfeeding because safety has not been established.
- Because it builds up slowly in the body, effects, including side effects, can persist for weeks after you stop taking it.
Side effects
Common effects include drowsiness, weight gain, dry mouth, fatigue and mild stomach upset, especially when starting treatment.
Stop and seek urgent medical care for any of these:
- Low mood, hopelessness, or thoughts of self-harm.
- New stiffness, slowness of movement, or tremor, which can signal drug-induced parkinsonism.
- An irregular heartbeat or fainting.
Safety essentials
- Flunarizine is linked to depression and parkinsonism-like movement symptoms with long-term use, particularly in people over 65. Your prescriber should reassess the need for treatment periodically, typically after about six months, and stop it if either problem appears.
- Do not drive or operate machinery until you know how flunarizine affects you, since drowsiness is common.
- Avoid alcohol and other sedating medicines, which can add to drowsiness.
This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.