Safety and efficacy of LSD as treatment for cluster headache: a randomized, double-blind, placebo-controlled phase II study

Cluster headache (CH) is often rated as the most painful of all primary headaches, which not only causes significant disability, but is also associated with enormous personal, economic, and psychiatric burden. At the moment, there is no specific treatment available for CH, but serotonergic compounds represent an important drug class, especially in the abortive management of cluster attacks. However, there is a need for new treatment approaches, as CH is also often insufficiently managed with available medication. This study will evaluate the potential benefit and safety of a treatment with LSD (pulse regimen) for patients with CH.