Abstract
This literature review examines if Echinacea purpurea, Bovine colostrum or Vitamin C has an effect on common cold infections. Effect is defined in this article as prevention, reduction of symptoms or decrease in duration of disease. The 9 clinical studies and 2 meta- analysis included in this literature review has not found statistically significant result by use of Echinacea purpurea, Bovine colostrums or Vitamin C versus placebo during common cold infection. Therefore I cannot recommend these products to patients, but since they have not shown serious side effects, I will not warn patients against using them.