Isn’t it humbling that we have no cure for the world’s most common illness? Yes, the common cold, globally the #1 cause of sick days and doctor visits, still stampedes across the world, blissfully immune to any Eastern or Western prescriptions. As a family doctor, I’m always a bit frustrated that I can’t offer much to these patients, at least in terms of Western allopathic medicines. So, I decided to scour the literature again to see if any new research has shown benefits from herbals and supplements. And the good news is yes: there may actually be a couple of supplements which can help you get better, quicker. Here’s my advice below. (Please note that this research is for treating, and not preventing, colds and flu.)

Evidence-Based Literature Search

When it comes to supplements and natural therapies, I use only a tiny handful of resources that I consider trustworthy. All are certified by the Health on the Net Foundation as sources of trustworthy medical information. All these sites would review only the best, most unbiased research, which usually means the gold standard of all research: placebo-controlled, randomized controlled trials. I strongly recommend that everyone use HONCode’s search engine anytime you’re looking for medical advice, especially regarding supplements. For example, you’ll never see the anti-vaccine snake-oil salesman Dr. Mercola on their list. Here are my favorite medical resources, and their evaluations of therapies for the common cold:

• The Natural Medicines Database, a fantastic resource for doctors, on their review of the common cold, doesn’t rank anything as “effective” or even “likely effective”. Their next level, “possibly effective,” lists andrographis, vitamin C, zinc logenzes, echinacea, and elderberry.
• The Encyclopedia of Natural & Alternative Treatments has a common cold review which concludes that zinc logenzes, echinacea, and andrographis all have fair evidence to shorten a cold and lessen symptoms. Others such as vitamin C, ginseng and garlic perhaps may help to prevent colds, but do not improve symptoms.
• The Cochrane Library, a well respected independent review board, reviewed common cold treatments and found poor evidence for most supplements, including vitamin C bursts. However, they did find that zinc lozenges at a total dose more than 75 mg during a cold can quicken recovery time. There was “weak evidence” for echinacea. They also reviewed a popular European herbal treatment for colds, pelargonium sidoides, and concluded that this herb may help with symptoms of acute rhinosinusitis and the common cold in adults, “but doubt exists.”
• The National Center for Complementary and Integrative Health (NCCIH), the official governmental agency, has a review of common cold products and supports oral zinc for treatment; it finds no strong benefit for vitamin C, echinacea or probiotics as treatments.

Let’s break it down into the supplements that have the most evidence:

• Zinc: This seems to have the most support, especially higher doses (>75 mg daily) of lozenges containing zinc gluconate or zinc acetate. Some good studies show reduction in cough, runny nose, headache, sore throat and overall time of illness. But side effects are common, especially nausea and a bad taste in the mouth. Also, definitely do not do the zinc nasal sprays, which have clear evidence to permanently cause loss of smell. The data suggests you should stick with lozenges and not pills. I see a few brands of logenzes up to 30 mg each, which at three times a day would help. I see a few popular brands with only 5 mg zinc each, which seems far too low to work. I wouldn’t advise using these for children.
• Echinacea: This is probably the one you’ve heard about, and the evidence is encouraging — but not totally clear. Some “double-blind, placebo-controlled studies have found that various forms and species of echinacea can reduce the symptoms and duration of a common cold, at least in adults. The best evidence is for products that include the above-ground portion of E. purpurea rather than the root.” But it’s very difficult for me to recommend a proper dose, as studies have used multiple regimens via drops, pills and teas, also using many types of echinacea, as well as different combinations of root and plant. Here’s a useful list of test results from ConsumerLab showing which brands in the USA have proper amounts of the herb.
• Andrographis peniculata: An Indian herb very popular in Ayurvedic medicine and now in Europe, I think this actually has some good evidence.  A handful of double-blind, placebo-controlled have shown benefit in reducing the duration and severity of cold symptoms, especially cough. An excellent meta-analysis of herbals from Germany showed significant improvement in severity and duration of a cough, especially via liquid formulation. The usual dose seems to be 48-500mg of the andrographolide aerial parts, usually divided three times a day. You can find a good list of andrographis brands on iherb.com. I keep reading about a Swedish patented combination with eleutherococcus and sambucus (Kan Jang Plus), but I don’t see it sold anywhere in the USA.
• Pelargonium sidoides (Umckaloabo): This is an interesting herbal, very popular in Europe and perhaps should be more popular here in the USA. That same German meta-analysis I mentioned above found strong evidence that it helped with cough, fevers, and sore throat — including for children as young as one year old, although the German independent Institute for Quality and Efficiency in Health Care says it shouldn’t be used for children under six years. The Cochrane Library also reviewed this herb and concluded, “P. sidoides may be effective in alleviating symptoms of acute rhinosinusitis and the common cold in adults, but doubt exists.” As with andrographis, the liquids and syrups were better than tablets. I see on iHerb a series of pelargonium products called Umcka with good reviews.
• Probiotics: Probiotics actually have pretty good evidence that taking them for months, especially over the winter, can markedly improve both the frequency and the severity of colds — for kids and for adults (as does vitamin D). That’s great news! But for symptom relief during a cold, the evidence is much more scant. I couldn’t find one good study for this; none of the groups above recommend probiotics as treatment.
• Vitamin C: Here’s another super popular supplement, which many people swear by. But again the evidence isn’t conclusive, and the few studies that do show a benefit show only mild improvement. Still, at least it seems safe for adults and children, and evidence is even stronger as a preventive during the cold seasons.

My Bottom Line

For immune boosting,  don’t forget the most important advice: get a good’s night sleep; eat a lot of anti-oxidant foods; and stay well hydrated.

In terms of supplements, I think it’s appropriate for adults (not kids) to try some of the above supplements — and the sooner, the better, within 24 hours of your symptoms starting.

For what it’s worth, here’s my plan for myself and my wife the next time we get a cold: we’re going to continue our usual vitamin C + zinc bursts, usually using Airborne effervescent tablets, three times a day. Emergen-C and Wellness Formula also are similar, all three with a ton of vitamin C, some zinc and an assortment of herbals, many of which are mentioned above. I’m also adding andrographis 400mg twice a day and also pelargonium; and I’ll continue doubling up on my probiotic supplement, despite the lack of evidence. (One small note: last week my wife tried andrographis for the first time and had a horribly itchy rash for days. I was fine.)

In general, for children, I’m still hesitant about using any of these herbals for children under 6 years old, and I remain cautious about what I use with my own kids, both under 4 years of age. I still like probiotics during a cold, and I’m a big fan of honey for cough for all ages above one year, which studies show works better than any OTC syrup. I’m encouraged with the European studies using pelargonium and also ivy/primrose/thyme syrups, some of which are partially included in American brands like Zarbees. For more age-specific advice, please look at the recommendations in my previous article about curing a cough.

What herbals and supplements have you used? Please leave comments below.

UPDATE 2024: Please follow me at my new website, DrSaintCyr.com. Also my new YouTube channel youtube.com/@drsaintcyr