Cafergot is used for preventing and treating certain kinds of headaches (e.g., migraines, migraine variants, histaminic cephalalgia). It may also be used for other conditions as determined by your doctor. 
Use Cafergot as directed by your doctor. 
Cafergot may be taken with or without food. 
Eating grapefruit or drinking grapefruit juice may affect the amount of Cafergot in your blood. Talk with your doctor before including grapefruit or grapefruit juice in your diet. 
Cafergot is only to be used as needed for a migraine attack. 
Take Cafergot at the first sign of a headache. If the initial dose does not relieve your headache, additional doses may be needed according to your doctor's instructions. Do not take a dose of Cafergot within 30 minutes of your last dose. 
Do not take more than 6 tablets for a single migraine headache or more than 10 tablets during any 7-day period without first checking with your doctor. 
Ask your health care provider any questions you may have about how to use Cafergot. 
Check with your doctor if any of these most common side effects persist or become bothersome: 
nausea. 
Seek medical attention right away if any of these severe side effects occur: 
severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blue color of the fingers or toes; chest pain or tightness; cold or pale fingers or toes; diarrhea; dizziness; hallucinations; headache; irregular heartbeat; leg cramps or weakness; mental or mood changes; muscle pain; numbness or tingling of the hands, feet, or skin; ringing in the ears; seizure; severe or persistent nausea or vomiting; shortness of breath; swelling; temporary fast or slow heartbeat; vomiting; weak pulse. 
If you miss a dose of Cafergot and you still have a headache, take it as soon as you remember. Do not take a dose of Cafergot within 30 minutes of your last dose. Do not take 2 doses at once. 
Storage
Store Cafergot at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Keep Cafergot out of the reach of children and away from pets.