February 15, 2019

Do favorite cold and flu remedies actually work?

It's that time of year — spring seems so far away. The temperatures are still freezing. And the office cold is going around. Again.

When you’re battling congestion, cough, a sore throat, headaches and all around achiness, you can get desperate for relief. And suddenly, your neighbor’s suggestion of eating raw garlic doesn’t seem so crazy. But does it actually work?

We posted the question to our Facebook audience, "What are your favorite cold and flu remedies?" and asked UW Health Family Medicine physician Dr. Adam Rindfleisch for his take.

Should you try a home remedy to treat a cold? Think ECHO

Whether it's that well-meaning neighbor's suggestion to eat raw garlic, or a parent who recommends using Vick’s Vaporub to halt a nighttime cough, Rindfleisch, who is also an Integrative Health specialist, says he uses ECHO to determine whether to try a particular therapy:

  • E: Efficacy – Does it work?

  • C: Cost – Is it affordable or can a person access it?

  • H: Harm – Are there any worries about side effects or complications?

  • O: Opinions – Does the person believe it will help them (or not)?

In reviewing the remedies suggested over Facebook, Rindfleisch said, "they all tend to be quite safe, when used appropriately at standard doses. The big question is, do they work?"

Cold and flu home remedies

Dr. Rindlfleisch refers to ECHO, and current research, as he provides the following responses to suggestions from our Facebook followers:

Vicks on the soles of your feet or Vicks on a cotton ball in an achy ear

The commercial product Vicks Vaporub contains camphor (from a type of laurel tree), menthol (from peppermint) and eucalyptus. Camphor is FDA approved because it is considered effective for cough. We don't have as much information about peppermint and eucalyptus, but inhaling the oils from them does seem to open airways.

Some reports indicate that menthol can cause airway spasm in infants, so I would avoid using for them.

Unfortunately, we know it is helpful to breathe Vicks, but how much it helps specifically from being on the feet or in your ear hasn't been studied.

Don't ever heat Vaporub up before you use it. It can retain a lot of heat and cause burns.

Hot water with lemon juice and a tablespoon of sugar

It never hurts to drink a lot of fluids when you have a cold. This probably does keep mucus loose, which means it will leave the body more easily. It isn't clear if lemon being added to tea – or sugar – makes a difference.

Honey for cough (or honey/lemon)

Honey does make a difference. A number of studies indicate that 1/2 to 2 teaspoons at bedtime can decrease nighttime cough and improve sleep in kids, and it has been found to be as good as or better than dextromethorphan or antihistamines, which are ingredients in most over the counter remedies. And remember, never give honey to children under the age of one.

Eat horseradish for sinusitis and sore throat

Horseradish hasn't been studied much for colds and coughs, but a 2006 German study did find that horseradish (combined with nasturtium, which isn't an herbal remedy you see often in cold treatment) was as effective as antibiotics for sinus congestion. Of course, part of that might be that in many cases, if there are no bacteria around and the sinuses are just congested, the antibiotics might not be all that helpful.

Raw garlic

Research is limited, but a 2001 study of 146 people did find that taking garlic from November through February decreased reports of cold-type infections. In the garlic group, there were 24 reports vs. 65 in the placebo group. Garlic is a food, of course, so overall it tends to be safe. Some experts say don't overdo it if you are taking blood thinners, though.

Slippery-elm tea for scratchy throat

I like to recommend slippery-elm lozenges for sore throats and slippery elm stirred into water for reflux with heartburn, but it hasn't been studied much for either. Should be safe to try, though.

Gargle hot water with crushed aspirin for a sore throat

Adding crushed aspirin to water as a gargle to treat sore throats has been studied in people who had sore throats after they were given a breathing tube during surgery. For them, it decreased soreness for about 4 hours per dose. Remember not to give aspirin to kids, because of risk of Reye's syndrome.

Oil of Thieves

Thieves oil is touted by a specific essential oils company as one of their special mixtures. The story goes that this combination of oils was used by thieves way back when so they could steal from places where plagues had struck without getting sick themselves. It contains oil from cloves, lemon, cinnamon and rosemary. While there are many testimonials out there, there isn't a lot of research. Applied to the skin, these should be safe, so long as they don't cause the rare allergic reaction.


In some old studies, they measured "nasal mucus velocity" (fun job!) for chicken soup versus hot water versus cold water. Soup was the most effective, then hot water, then cold water. At least in test tube-studies, chicken soup also seems to settle down the activity of some types of white blood cells, which can help.

Zinc to shorten the duration of a cold

Study findings vary a lot on this one – 9 to 24 mg of elemental zinc taken every 2 hours within 48 hours after a cold starts seems to help shorten symptoms by about a day and a half, according to some studies. Too much zinc can lower your body's copper stores, but these doses, taken over several days, should not cause problems.

Other approaches people use include Echinacea, vitamin C, and elderberry. All three are a bit controversial, but tend to be safe. Elderberry does seem to decrease flu symptoms. Vitamin C seems to help in kids and people under physical stress, but at high doses, some people get gastrointestinal symptoms.

The article provides general health information and is not specific advice intended for any particular individual(s). It is not a professional medical opinion or a diagnosis. Always consult your personal health care provider about your concerns.