title: Complementary and alternative medicine for prevention and treatment of the common cold.
abstract: OBJECTIVE
  To review the evidence supporting complementary and alternative medicine approaches to treatment and prevention of the common cold in adults.
  
  
  METHODS
  MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews were searched from January 1966 to September 2009 combining the key words common cold or influenza with echinacea, garlic, ginseng, probiotics, vitamin C, and zinc. Clinical trials and prospective studies were included.
  
  
  RESULTS
  For prevention, vitamin C demonstrated benefit in a large meta-analysis, with possibly increased benefit in patients subjected to cold stress. There is inconsistent evidence for Asian ginseng (Panax ginseng) and North American ginseng (Panax quinquefolius). Allicin was highly effective in 1 small trial. For treatment, Echinacea purpurea is the most consistently useful variety; it was effective in 5 of 6 trials. Zinc lozenges were effective in 5 of 9 trials, likely owing to dose and formulation issues. Overall, the evidence suggests no benefit from probiotics for prevention or treatment of the common cold.
  
  
  CONCLUSIONS
  Vitamin C can be recommended to Canadian patients for prevention of the common cold. There is moderate evidence supporting the use of Echinacea purpurea and zinc lozenges for treatment. Ginseng and allicin warrant further research.
authors.affiliation: Seekers Centre for Integrative Medicine, Ottawa, ON. richard@seekerscentre.com
authors.forename: Richard
authors.initials: R
authors.lastname: Nahas
authors.forename: Agneta
authors.initials: A
authors.lastname: Balla
mesh_terms: D001205:Ascorbic Acid / Q000627:therapeutic use; D003139:Common Cold / Q000517:prevention & control* / Q000628:therapy; D000529:Complementary Therapies; D019587:Dietary Supplements; D004220:Disulfides; D020900:Echinacea; D005737:Garlic; D005942:Gluconates / Q000627:therapeutic use; D005998:Glycine / Q000627:therapeutic use; D006801:Humans; D005894:Panax; D010936:Plant Extracts / Q000627:therapeutic use; D019936:Probiotics / Q000627:therapeutic use; D013441:Sulfinic Acids / Q000627:therapeutic use; D014815:Vitamins / Q000627:therapeutic use; D015032:Zinc / Q000627:therapeutic use
chemical_list: D004220:Disulfides; D005942:Gluconates; D010936:Plant Extracts; D013441:Sulfinic Acids; D014815:Vitamins; C437626:zinc gluconate glycine; C006452:allicin; D015032:Zinc; D001205:Ascorbic Acid; D005998:Glycine