Smoking marijuana and taking its legal medicinal derivative, dronabinol helped one patient with cluster headaches, according to a report from the Montefiore Headache Clinic. Dronabinol is approved for the treatment of nausea and loss of appetite. The effectiveness of smoking marijuana or taking dronabinol for the relief of pain has been reported by many patients, but never proven in large trials. I generally discourage patients trying marijuana for the relief of any symptoms, unless they have tried and failed traditional medications and they have already tried marijuana and it did help. Marijuana not only has many negative effects on the body, but can be also contaminated by other harmful substances. Cluster headaches can be extremely intense and at times lead patients to thoughts of suicide. In view of this report it seems reasonable to try dronabinol in patients who failed Imitrex injections, oxygen and preventive drugs, such as high dose of verapamil, lithium, and topiramate.