title: Purpura and bleeding due to calcium-channel blockers: an underestimated problem? Case reports and a pilot study.
abstract: BACKGROUND
  Surgical bleeding and occasionally purpura due to calcium-channel blockers have been described.
  
  
  OBJECTIVE
  To present cases in whom purpura or internal bleeding due to calcium-channel blockers was a presenting feature, including one subject with drug-induced haematuria and haematospermia due to amlodipine and one with the Rumpel-Leede sign. Further support for a true association was sought in a pilot study using Hess testing to provoke purpuric skin lesions.
  
  
  METHODS
  Four representative cases presenting due to purpura or bleeding are described, all of whom had an abnormal Hess test. A further 19 patients taking calcium-channel blockers and 13 control subjects were also tested.
  
  
  RESULTS
  Of 19 patients on calcium-channel blockers, 16 had either abnormal Hess results (n = 13) or marked acral purpura (n = 3) after a Hess test procedure. A similar abnormal response, of milder degree, occurred in only 2 of 13 control subjects.
  
  
  CONCLUSIONS
  The high frequency of purpura shown in this study, whether spontaneous or provoked, suggests that this is a pharmacological class effect rather than idiosyncratic. Purpura in patients taking these drugs may be a clue to diagnosis of internal or postsurgical bleeding. We conclude that purpura related to calcium-channel antagonists is probably underestimated, but further studies are needed to identify the mechanism by which this occurs.
authors.affiliation: Department of Dermatology, Cumberland Infirmary, Carlisle, UK. neil.cox@ncumbria-acute.nhs.uk
authors.forename: N H
authors.initials: NH
authors.lastname: Cox
authors.forename: M L
authors.initials: ML
authors.lastname: Walsh
authors.forename: R H
authors.initials: RH
authors.lastname: Robson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017311:Amlodipine / Q000009:adverse effects*; D002121:Calcium Channel Blockers / Q000009:adverse effects*; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000009:adverse effects*; D010865:Pilot Projects; D011693:Purpura / Q000139:chemically induced* / Q000473:pathology
chemical_list: D002121:Calcium Channel Blockers; D017311:Amlodipine; D009543:Nifedipine