Which medication is used for migraine prophylaxis?

Amitriptyline is commonly used for migraine prophylaxis due to its effectiveness in reducing the frequency and severity of migraine attacks. It is a tricyclic antidepressant that works by modulating neurotransmitters in the brain, including serotonin and norepinephrine. This modulation can help stabilize nerve activity and reduce the occurrence of migraines.

In clinical practice, Amitriptyline is often preferred for patients who experience frequent migraines, and it can also assist with co-morbid conditions like anxiety or depression. Its efficacy in migraine prophylaxis is supported by numerous studies, making it a standard choice in managing chronic migraine sufferers.

Other medications listed, such as ergot, naproxen, and clonidine, are not primarily indicated for prophylaxis. Ergot is typically used for abortive treatments during a migraine attack rather than prevention, while naproxen is a nonsteroidal anti-inflammatory drug (NSAID) that is also more suited for acute treatment. Clonidine's role is more related to hypertension management and does not have a strong evidence base for migraine prevention. Therefore, Amitriptyline stands out as the correct choice for migraine prophylaxis.