title: Sildenafil can trigger cluster headaches.
abstract: Phosphodiesterase-5 inhibitors commonly trigger migraines but rarely trigger cluster headaches. Two cases of cluster headaches triggered by sildenafil are described.
authors.forename: Randolph W
authors.initials: RW
authors.lastname: Evans
mesh_terms: D000328:Adult; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D003027:Cluster Headache / Q000139:chemically induced*; D007172:Erectile Dysfunction / Q000150:complications / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D010879:Piperazines / Q000009:adverse effects* / Q000627:therapeutic use; D011687:Purines; D000068677:Sildenafil Citrate; D013450:Sulfones; D014700:Verapamil / Q000627:therapeutic use
chemical_list: D002121:Calcium Channel Blockers; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate; D014700:Verapamil