February 6, 2014
Evidence-Based Advice on Preventing, Treating Common Cold

Edmonton, Alberta—The cold may be common, but good medical evidence on how to prevent and treat the illness has been in short supply.

In a recent review published by the Canadian Medical Association Journal, researchers from Canada and Australia culled through clinical studies on the condition and provide support for many of the suggestions pharmacists traditionally have offered: Handwashing and zinc supplements appear to be most effective in preventing colds, while acetaminophen and ibuprofen—with the addition of antihistamine/decongestant combinations in some situations—are the best for treatment.

Background in the article noted that, on average, the common cold affects adults two to three times a year but occurs about six times a year in children under age 2. The symptoms, including sore throat, stuffy or runny nose, cough and malaise, are usually most severe in the first three days of a cold, although some effects can last 7 to 10 days or even as long as 3 weeks.

“Although self-limiting, the common cold is highly prevalent and may be debilitating. It causes declines in function and productivity at work and may affect other activities such as driving,” write the authors from the University of Alberta in Edmonton, Canada, and the University of Auckland in New Zealand.

The review of 67 randomized controlled trials (RCTs) indicated that handwashing, as well as alcohol disinfectants and gloves, is likely effective in preventing a cold. The authors also note that zinc may aid in prevention for children, and possibly adults, with at least two RCTs finding that children who took 10 or 15 mg of zinc sulfate daily had lower rates of colds and fewer absences from school due to colds.

While some evidence exists on the effectiveness of probiotics in preventing colds, according to the review, comparison was difficult because of the wide variety of organisms and formulations in the studies examined.

As for treatment, the review added evidence to many of the recommendations already made by healthcare professionals:

• Pain relievers such as ibuprofen and acetaminophen can help with pain and fever, although the studies indicated that ibuprofen appears better for fever in children.
• For adults and older children, antihistamines combined with decongestants and/or pain medications appear to be somewhat or moderately effective in treating colds. The treatment was not recommended in children under age 5.
• Nasal sprays such as ipratropium can help with runny noses but have no effect on congestion.

The benefits of some common home remedies and alternative therapies, such as ginseng, gargling, vapor rubs and homeopathy, were unclear in the study. Cough medicines showed no benefit in children but appeared to be slightly helpful for adults.

Honey was found to have a small effect in relieving cough symptoms in children older than a year-old, but vitamin C did not.

With bacterial infections involved in fewer than 5% of colds, the authors note, antibiotics were of no benefit for most patients.

“Much more evidence now exists in this area, but many uncertainties remain regarding interventions to prevent and treat the common cold,” write the authors. “We focused on RCTs and systematic reviews and meta-analyses of RCTs for therapy, but few of the studies had a low risk of bias. However, many of the results were inconsistent and had small effects (e.g., vitamin C), which arouses suspicion that any noted benefit may represent bias rather than a true effect.”

U.S. Pharmacist Social Connect