title: Subcutaneous sumatriptan induces changes in frequency pattern in cluster headache patients.
abstract: OBJECTIVE
  To document the relationship between the use of subcutaneous (SQ) sumatriptan (sum) and a change in frequency pattern of cluster headache (CH) in six patients. To discuss the clinical and pathophysiological implications of this observation in the context of available literature.
  
  
  BACKGROUND
  Treatment with SQ sum may cause an increase in attack frequency of CH but data from literature are scant and controversial.
  
  
  METHODS
  Six CH sum-naïve patients (three episodic and three chronic according to the International Headache Society (IHS) criteria) are described.
  
  
  RESULTS
  All six patients had very fast relief from pain and accompanying symptoms from the drug but they developed an increase in attack frequency soon after using SQ sum. In all patients, the CH returned to its usual frequency within a few days after SQ sum was withdrawn or replaced with other drugs. Five patients were not taking any prophylactic treatment and SQ sum was the only drug prescribed to treat their headache.
  
  
  CONCLUSIONS
  Physicians should recognize the possibility that treatment of CH with SQ sum may be associated with an increased frequency of headache attacks.
authors.affiliation: Headache Centre, INI Grottaferrata, Rome, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Rossi
authors.forename: Giorgio Di
authors.initials: GD
authors.lastname: Lorenzo
authors.forename: Rita
authors.initials: R
authors.lastname: Formisano
authors.forename: M Gabriella
authors.initials: MG
authors.lastname: Buzzi
mesh_terms: D000328:Adult; D003027:Cluster Headache / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007279:Injections, Subcutaneous; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D017366:Serotonin Receptor Agonists / Q000008:administration & dosage* / Q000009:adverse effects; D018170:Sumatriptan / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D017366:Serotonin Receptor Agonists; D018170:Sumatriptan