title: Titrated initiation of acetylsalicylic acid-dipyridamole therapy reduces adverse effects and improves tolerance in patients with stroke.
abstract: BACKGROUND
  Standard aspirin (acetylsalicylic acid [ASA])-dipyridamole therapy twice daily is associated with high rates of discontinuation in large part because of headache and gastrointestinal side effects. Attempts to address dipyridamole-induced headache through reduced dose initiation have produced variable results. Moreover, it has been suggested that migraineurs are more likely to have a dipyridamole-induced headache.
  
  
  OBJECTIVE
  We sought to evaluate whether titrated initiation of ASA-dipyridamole in patients with stroke/transient ischemic attack (TIA) improves tolerance and to assess the appearance of headache in those with pre-existing history of headaches.
  
  
  METHODS
  ASA-dipyridamole (25/200 mg) once daily together with ASA (81 mg) daily was started in 130 patients given the diagnosis of stroke/TIA with instructions to increase ASA-dipyridamole to twice daily after 7 days and discontinue ASA (81 mg). Patients received a telephone call on days 7 and 14 to assess for adverse events, discontinuation, and recurrent stroke/TIA.
  
  
  RESULTS
  Two patients were lost to follow-up. After 2 weeks, 113 patients were using the medication without any major complications. Fifteen patients were off therapy; 10 (8%) patients stopped because of headache and/or gastrointestinal symptoms, whereas 4 patients were switched to other antiplatelet agents by their primary care physician as a matter of choice rather than ASA-dipyridamole side effects. One patient had recurrent stroke because of intracranial dissection and was switched to anticoagulation. Only 4 of 27 (14%) patients with a history of headache discontinued therapy.
  
  
  CONCLUSIONS
  Titrated initiation of ASA-dipyridamole (25/200 mg) appears to have low discontinuation rate and approximately 90% tolerance after 2 weeks. History of migraine or tension headaches was not directly associated with discontinuation because of headaches.
authors.affiliation: Department of Neurology, Trillium Health Centre, Mississauga, Ontario, Canada. adouen@thc.on.ca
authors.forename: André G
authors.initials: AG
authors.lastname: Douen
authors.forename: Sejla
authors.initials: S
authors.lastname: Medic
authors.forename: Mehreen
authors.initials: M
authors.lastname: Sabih
authors.forename: Nicole
authors.initials: N
authors.lastname: Pageau
authors.forename: Ashfaq
authors.initials: A
authors.lastname: Shuaib
mesh_terms: D000241:Adenosine / Q000378:metabolism; D000368:Aged; D001241:Aspirin / Q000008:administration & dosage* / Q000009:adverse effects*; D002536:Cerebral Arteries / Q000187:drug effects / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D004176:Dipyridamole / Q000008:administration & dosage* / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D004361:Drug Tolerance / Q000502:physiology; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000009:adverse effects; D006261:Headache / Q000139:chemically induced* / Q000503:physiopathology / Q000517:prevention & control; D006801:Humans; D008297:Male; D008881:Migraine Disorders / Q000150:complications / Q000503:physiopathology; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects; D020521:Stroke / Q000188:drug therapy* / Q000517:prevention & control; D016896:Treatment Outcome; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology
chemical_list: D005343:Fibrinolytic Agents; D010726:Phosphodiesterase Inhibitors; D004176:Dipyridamole; D000241:Adenosine; D001241:Aspirin