The Uncommon Nuisance

"The common cold is so common, adults get, on average, two to three a year, kids get six a year and elderly people about one. [And while Vitamin C] may provide some benefit in people under physical stress (e.g. marathon runners or soldiers in sub Arctic environments), [29 trials involving over 11,300 people where vitamin C was tested for cold prevention found] no meaningful benefit in the average patient."
Dr. Michael Allan, associate professor, department of family medicine, University of Alberta

The "average adult would need to use Vitamin C for 10 or 15 years to prevent one cold", is but one little tidbit of information resulting from a new review on the prevention and treatment of the common cold. The review saw publication this week in the Canadian Medical Association Journal. The common cold's impact "on society and health care is large", said Dr. Allan, who with Bruce Arroll of the University of Auckland, New Zealand, authored the review.

Antihistamine-decongestant combinations for adults, they write, may offer "small to moderate" relief of symptoms, but nasal irrigation, humidified air, garlic, Chinese herbal medicines and echinacea? Forget it, the relief experienced is hardly to be noticed. There goes common wisdom; uncommonly unhelpful, not only inadequate but downright useless, according to the good doctors.

The common cold:

"An acute, self-limiting viral infection of the upper respiratory tract involving the nose, sinuses, pharynx and larynx."

It is a condition whose symptoms tend to peak in one to three days, lasting from seven up to ten days. Infections lingering three weeks are not usual, but yet not entirely uncommon. Within the adult community, risk factors of 'catching' that common cold rest with stress and poor sleep. Entirely different for preschoolers for whom the primary risk factor is attending a daycare centre.


How to avoid contracting the virus? You've heard this advice ad infinitum: Wash Your Hands!

Apart from frequent hand-washing, zinc may prove to be of benefit in reducing the number of colds per year, particularly in children. The authors note two randomized controlled trials from Iran which tested zinc sulphate supplements of 10 mg or 15 mg daily and which appeared to produce fewer colds in winter months among the zinc group than among the placebo group.

Despite which, Dr. Allan said, "I certainly don't want to be telling parents to put their children on zinc every day to prevent the common cold. The research is not very robust." Then why, distinguished doktor, even mention it?

Those studies suggest zinc may shorten cold duration in adults by some 1.5 days, with mixed results. "Kids in these studies did not get a benefit, but adults did", he said, cautioning that zinc should never be used via nasal spray. "A few cases have linked it to the loss of smell".

Probiotics? May be helpful preventing upper respiratory tract infections in children and adults. Ginseng's role in preventing colds remains "questionable" since results from several studies provided "inconsistent results."

What, then does work? Antihistamines combined with decongestants have small to moderate effects on adult cold symptoms. But over-the-counter decongestants, antihistamine-decongestant combinations or cough suppressants give no benefit to children "and Health Canada recommends against their use in children under the age of six years".

Three randomized controlled trials on the other hand, looking at the use of honey for children with coughs demonstrated a measurable but small benefit in children over a year. (Honey should never be given to children younger than a year in age.) One dose (2.5 mg to 10 mg) of honey at bedtime seems to help improve children's coughing and therefore their sleep, as well.

Acetaminophen and non-steroidal anti-inflammatory drugs can help relieve aches and pain and fever though Ibuprofen is slightly better at treating fever in children. Workdays lost to illness or caring for a sick children accounted for $25-billion a year in the United States alone.