Medical Health Encyclopedia

The following are some conditions and substances that might trigger cluster attacks.

• Alcohol.
• High altitudes (trekking, air travel).
• Bright light (including sunlight).
• Exertion.
• Heat (hot weather, hot baths).
• Foods high in nitrites (such as bacon and preserved meats).
• Certain medications (including those that cause blood vessel dilation, such as nitroglycerin, and various blood pressure medications).
• Cocaine.

Text Continues Below

---

Triggers usually have an effect only during active cluster cycles. When the disorder is in remission, such triggers rarely set off the headaches. Of interest, however, was a case in which a man's cluster headaches were triggered only during coughing and sneezing. Treatment with indomethacin was effective in preventing the headaches.