... migraine headaches. Almotriptan is a headache medicine. It is believed to work by narrowing the blood vessels around the brain. Almotriptan also reduces ... in the body that can trigger headache pain, nausea, sensitivity to light and sound, and other migraine symptoms. Almotriptan often ... pain of a Migraine, such as nausea, vomiting, sensitivity to light, and sensitivity to sound. Almotriptan 99% HPLC