Principal Proposed Treatments
Other Proposed Natural Treatments
- Combination Product Containing Horseradish and Nasturtium
- Green Tea Extract
- Ivy Leaf
- Multivitamin/Multimineral Supplement
- Pelargonium sidoides
- Thymus Extract
- Traditional Chinese Herbal Medicine
- Vitamin D
Probably Not Effective Treatments
A cold is a respiratory infection caused by one of hundreds of possible viruses. However, because these viruses are so widespread, it is perhaps more accurate to say that colds are caused by a decrease in immunity that allows one of these viruses to take hold.
Colds occur more frequently in winter, but no one knows exactly why. Nearly everyone catches colds occasionally, but some people catch colds quite frequently, and others tend to stay sick an unusually long time.
Influenza B, commonly called the flu, occurs in the form of a worldwide epidemic every winter. The predominant symptoms of flu are fever, malaise, and muscle aches. Cold-like respiratory symptoms are usually fairly minor with the flu. However, a dangerous type of pneumonia can develop as a complication of influenza, especially in seniors.
People often want to take antibiotics for colds, and many physicians will prescribe them—even though antibiotics have no effect on viruses. Many believe that when the mucus turns yellow, it means that a bacterial infection has occurred for which antibiotic treatment is indicated. However, viruses can also produce yellow mucus and even if bacteria have made a home in the excess mucus, they may be only innocent bystanders and produce no symptoms.
Colds, however, can be complicated by bacterial infections. In such cases, antibiotic treatment may be indicated.
The situation is somewhat better for influenza. The “flu shot” provides protection against several strains of influenza. There are also prescription antiviral medications that can help prevent flu and also reduce its length and severity if you do come down with it.
Principal Proposed Natural Treatments
Various natural treatments have shown promise for treating or preventing colds, which are described below. See also the treatments discussed in the Acute Bronchitis article.
One famous alternative treatment for colds is the use of zinc in nasal gel or lozenges. When you take zinc this way, you are not using it as a nutrient. Rather, certain forms of zinc release ions that are thought to directly inhibit viruses in the nose and throat.
Note : With zinc, more is not better; once you do have enough zinc, getting extra will not help, and might even hurt.
Until the 1930s, echinacea was the number one cold and flu remedy in the United States. It lost its popularity with the arrival of sulfa antibiotics. Ironically, sulfa antibiotics are as ineffective against colds as any other antibiotic, while echinacea does seem to be at least somewhat helpful. In Germany, echinacea remains the main remedy for minor respiratory infections.
Echinacea purpurea Echinacea angustifolia Echinacea pallida E purpurea E. purpurea E. pallida
Echinacea has shown promise for reducing the symptoms and duration of colds and aborting a cold once it has started. However, echinacea does not appear to be helpful for preventing colds. It may also not be effective in children.
E. purpurea E. purpurea
E. purpurea E. purpurea
E. purpurea E. angustifolia E. angustifolia
E. purpurea E. purpurea
Participants took either echinacea or placebo at a dosage of 20 drops every 2 hours for 1 day, then 20 drops 3 times a day for a total of up to 10 days of treatment. The results were promising. Fewer people in the echinacea group felt that their initial symptoms actually developed into "real" colds (40% of those taking echinacea versus 60% taking the placebo actually became ill). Also, among those who did come down with "real" colds, improvement in the symptoms started sooner in the echinacea group (4 days instead of 8 days). Both of these results were statistically significant.
Several studies have attempted to discover whether the daily use of echinacea can prevent colds from even starting, but the results have not been promising.
E. purpurea Note
For more information, including dosage and safety issues, see the full Echinacea article.
According to a few, well-designed studies (almost all of which used the proprietary extract produced by a single company), andrographis can reduce the symptoms of colds. It may offer the additional useful benefit of helping to prevent colds.
By the end of the trial, only 16 people in the group using andrographis had experienced colds, compared to 33 of the placebo-group participants. This difference was statistically significant, indicating that andrographis reduces the risk of catching a cold by a factor of two as compared to placebo.
For more information, including dosage and safety issues, see the full Andrographis article.
Vitamin C may mildly reduce symptoms of colds when they occur, but it probably does not help prevent colds.
For more information, including dosage and safety issues, see the full Vitamin C article.
Although most people in the West think of ginseng as a stimulant, in Eastern Europe ginseng is widely believed to improve overall immunity to illness. As we have seen, echinacea does not seem to prevent respiratory infections. But it appears that regular use of ginseng might be able to provide this important benefit.
There are three different herbs commonly called ginseng: Asian or Korean ginseng ( Panax ginseng) , American ginseng ( Panax quinquefolius ), and Siberian "ginseng" ( Eleutherococcus senticosus ). The latter herb, which is not discussed here, is actually not ginseng.
For more information, including dosage and safety issues, see the full Ginseng article.
The herb garlic has a long history of use for treating or preventing colds. However, up until 2001, there was no scientific evidence that it actually works for this purpose. In fact, many people joked that garlic merely makes you smell so bad people stay away from you, and so you do not catch their cold.
However, there is now some evidence that garlic may really work.
The results showed that participants receiving garlic were almost two-thirds less likely to catch cold than those receiving placebo. Furthermore, participants who did catch cold recovered about one day faster in the garlic group as compared to the placebo group.
Note that these studies do not indicate that taking garlic will help once you already have a cold.
For more information, including dosage and safety issues, see the full Garlic article.
Probiotics are healthy organisms that colonize the digestive tract. Not only can they help preventive intestinal infections, they appear to help prevent colds as well.
- Actimel with L. paracasei (L. casei), Streptococcus thermophilus, and Lactobacillus bulgaricus
- L. plantarum HEAL 9 plus L. paracasei 8700:2
- Lactobacillus rhamnosus strain GG
- L. rhamnosus plus Bifidobacterium lactis Bb-12
- Lactobacillus acidophilus plus Bifidobacterium bifidum
- L. acidophilus plus L. casei
For more information on these “friendly bacteria," see the full Probiotic article.
Other Proposed Natural Treatments
Various other natural treatments have shown some promise for preventing or treating colds and flus.
Preventing Respiratory Infections
Various herbs are said to enhance immunity over the long term, including ashwagandha , astragalus , garlic , maitake , reishi , and suma . However, there is as yet no meaningful evidence that they really work. In addition, several herbs, including ginger , kudzu , osha , and yarrow , are said to help avert colds when taken at the first sign of infection; but again, there is no scientific evidence that they are effective.
Treatment of Respiratory Infections
Other herbs sometimes recommended to reduce cold symptoms, but that lack meaningful supporting scientific evidence, include hyssop , ivy leaf , linden , marshmallow , mistletoe , mullein , oregano , and peppermint .
Homeopathic approaches to colds and flus are also discussed in the Homeopathy database, in two separate chapters titled, respectively, influenza and common cold.
- Reviewer: EBSCO CAM Review Board
- Review Date: 09/2014 -
- Update Date: 03/19/2015 -