You’ll notice that the common cold makes a comeback as the weather begins to cool down in autumn. As do complementary medicines for many people to prevent and treat common cold symptoms such as a runny nose, sore throat and headache. But complementary medicines for colds have mixed results, what does the research have to say on their effectiveness?
Vitamin C has been in popular use for the common cold for at least 40 years. During this time many studies have been done. However there are mixed results.
An analysis of the research has found that 200 mg or more a day of vitamin C doesn’t reduce the chances of you catching a cold. But it may shorten how long a cold lasts by up to 1 ½ days and decrease how severe it feels.
The research is also mixed for zinc, a mineral used for prevention and treatment. On the one hand, if taken within 24 hours of cold symptoms appearing, zinc decreases how long it lasts and the severity of symptoms. And if taken continuously for a minimum of five months, it can reduce the chances of catching a cold.
But there are notable side effects. Zinc lozenges can cause a bad taste in your mouth and nausea, and nasals sprays may reduce your ability to smell, possibly for good.
While some studies find that echinacea, a herbal remedy, shortens how long a cold lasts and severity of symptoms, other studies don’t. As a result, at this stage the best that can be said about echinacea is that more research needs to be done.
For more information visit nccam.nih.gov/health and speak to your doctor about the effectiveness and safety of complementary medicines, particularly potential side effects and drug interactions.