A new review of studies helps weed out what works -- and what doesn't -- when it comes to preventing and treating the common cold.
What does seem to work at preventing a cold: Washing your hands. And for kids (and maybe even adults), taking zinc could decrease the rates of colds and related school absences.
"Although the evidence for cold prevention with zinc comes from studies involving only children, there is no biological reason why zinc would work only in children and not adults," the researchers wrote in the study.
Probiotics also seem to work, but the ones used in the reviewed studies had different formulations, thereby making it difficult to really compare them.
As for treatments, antihistamines with decongestants and/or pain medications seemed to help for kids older than 5 and adults. And ibuprofen and acetaminophen effectively reduced pain and fever (for kids, ibuprofen seemed to work better at reducing fever). Ipratropium nasal spray also seemed to help with runny nose, but not congestion.
What doesn't seem to work? For kids, cough medicines (though they could help a little bit for adults). Honey for kids over age 1 seemed to help receive cough. There was not clear evidence that vapor rubs, gargling, ginseng or homeopathy helped to treat colds, nor vitamin C or antibiotics.
"It is not possible to determine whether benefit exists for most other alternative therapies," researchers wrote in the study. "Studies of nasal irrigation, humidified air, Chinese herbal medicines and echinacea all showed inconsistent results."
The review, published in the Canadian Medical Association Journal, included dozens of studies, and was conducted by researchers from the University of Alberta and the University of Auckland.