title: Renin-angiotensin system mediators and Raynaud's phenomenon.
abstract: OBJECTIVE
  To review the use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) in the treatment of Raynaud's phenomenon (RP).
  
  
  METHODS
  Biomedical literature was accessed through July 2006 via PubMed, the Iowa Drug Information System (IDIS), and Cumulative Index to Nursing and Allied Health Literature (CINAHL) Plus. PubMed database terms included Raynaud's disease, angiotensin-converting enzyme inhibitors, and angiotensin II type 1 receptor blockers [pharmacological action]; IDIS terms included hypotensive agents-ace inhib 24080200, raynaud's syndrome 443.0, and hypotensive agents-angioten II 24080400; and CINAHL Plus terms included Raynaud's disease, angiotensin-converting enzyme inhibitors, losartan, and irbesartan.
  
  
  METHODS
  All clinical trials published in English that reported both subjective and objective outcomes of efficacy were reviewed.
  
  
  RESULTS
  Several small, short-term studies have evaluated captopril, enalapril, and losartan in the treatment of RP. The studies of ACE inhibitors have found conflicting results in their ability to improve digit blood flow and reduce both frequency and severity of RP attacks. Two studies have focused on the use of losartan for RP treatment, with both finding a statistically significant reduction in attacks and one showing improvement in symptoms of RP in comparison with the commonly utilized calcium-channel blocker, nifedipine. Most of the studies were short term (< or =12 wk) and included a limited number of patients (<60).
  
  
  CONCLUSIONS
  ACE inhibitors and ARBs may provide some minor benefits in the relief of RP, although no definite evidence exists to suggest that they are superior to traditionally used treatments such as calcium-channel blockers. Larger, randomized controlled trials of longer duration are needed to compare the effectiveness of ACE inhibitors and ARBs with conventional treatment.
authors.affiliation: College of Pharmacy, The University of Iowa, Iowa City, IA 52242-1009, USA.
authors.forename: Heidi M
authors.initials: HM
authors.lastname: Wood
authors.forename: Michael E
authors.initials: ME
authors.lastname: Ernst
mesh_terms: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D011928:Raynaud Disease / Q000188:drug therapy* / Q000378:metabolism; D011945:Receptors, Angiotensin / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000187:drug effects* / Q000502:physiology
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D011945:Receptors, Angiotensin