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Common Cold Centre | A centre of excellence devoted to the development of new treatments for coughs, colds and hay fever.

Alternative Common Cold Medications

Are alternative medicines any use for treating the common cold?

Conventional medicines provide only relief from symptoms and do not work against the virus or help our immune system to throw off the infection.

There is evidence that some alternative medicines such as zinc and Echinacea may help prevent the onset of common cold symptoms or shorten the duration of symptoms.

Alternative medicines are 'big business'

In the USA it has been estimated that at least one third of the population uses alternative medicines. In Europe the percentage is even higher, being from 40 - 70% in some cases.

The scientific and medical establishments have been defeated by this most common of diseases

The popularity of alternative medicines for common cold treatment may be due to the perception by the public that the scientific and medical establishments have been defeated by this most common of diseases. Since a common cold is usually of no great consequence to the vast majority of patients, and is a self limiting disorder, it is normally treated by self medication without resource to medical consultation.

The common cold does exact a tremendous toll in morbidity and economic cost

In the USA it is estimated that the annual economic burden of common colds through lost working days etc. is around $5 billion . The conventional common cold medicines available at present only help to alleviate the symptoms of the common cold and that is why there has been a move towards self medication with alternative medicines which may help to prevent infection.

What are alternative medicines?

Alternative medicine are used instead of or as a complement to conventional medicines.

One should not dismiss this type of alternative medicine as many of our our most potent modern medicines have developed from herbal medicines. Asprin was developed from salicylic acid found in the bark of the Willow tree; morphine and codeine from the Opium poppy; atropine from the Deadly nightshade plant; digitalis from the Foxglove, and there are many other examples.

Why do plants produce biochemicals that are useful in treating human diseases?

The most common diseases of mankind are related to microbial infection and this is also true for plant diseases as plants are commonly infected by bacteria, fungi and viruses. With the process of evolution over millions of years plants have developed their own antimicrobial biochemicals and these also act against the microbes that cause human disease.

Plants also defend themselves against being eaten by predators

Plants contain a very wide range of biochemicals some of which taste very bitter or acidic, some of which have pharmacological and sometimes toxic actions on predators such as snails, insects and mammals . Many of these plant biochemicals have useful antimicrobial and pharmacological properties for the treatment of human disease. Menthol found in the mint plant anaesthetises snails and caterpillars and protects the plant from predators.

Koala and eucalyptus

The eucalyptus tree produces a range of chemicals which are toxic to insects and other animals. The Koala is one of the few animals that can stomach the large amounts of eucalyptus and othe chemicals found in the leaves of this tree.

MENTHOL

Essential oils such as those containing menthol and eucalyptus have been used for hundreds of years for the treatment of common cold. Menthol is a major component of cornmint and peppermint oil, and eucalyptus oil is obtained from the eucalyptus tree. Menthol provides relief from nasal congestion by causing a cool sensation in the nose and also relieves the symptoms of sore throat and cough by a local anaesthetic action. The antimicrobial activity of essential oils such as menthol may also help to inhibit infection of the airway by pathogenic viruses and bacteria.

GARLIC

Prophylactic use of garlic is claimed to help prevent common cold and influenza infections and this action may be due to some antimicrobial action of garlic. A sulphur containing compound, Ajoene, derived from garlic, has been shown to have broad spectrum antimicrobial activity and is also reported have some antiviral and antiprotozoal activity.

ECHINACEA

Echinacea is the scientific name for the daisy like purple cone flower that is a very common wild flower across the United states. Folk lore tells us that the native Americans used this plant to treat coughs, colds and sore throats.There is some scientific evidence which indicates that Echinacea does affect our immune system by stimulating the activity of white blood cells.

Lozenges containing Echinacea may help prevent infection by boosting the immune system and could in theory abort a common cold infection and prevent the development of symptoms.

ZINC

Zinc is important in the diet as a trace element as over 80 enzymes are known to require zinc for their normal activity. Zinc also plays a role in the synthesis of proteins and zinc ions have been shown to inhibit viral replication in the test tube by inhibiting the synthesis of the proteins which form the viral shell . It has also been proposed that zinc medications may coat the common cold viruses such as the rhinovirus and prevent them from attaching to the nasal cells .

Zinc is good for you!

A variety of abnormalities of the immune system have been associated with zinc defficency and even a mild defficency of zinc in humans is reported to cause an imbalance of circulating lymphocyte white cells .

Zinc and common cold

The use of zinc lozenges to treat the common cold was first considered by George Eby who found that treatment with a zinc gluconate lozenge shortened the duration of common cold symptoms. The original positive finding by Eby was followed by a series of clinical trials on zinc lozenges of various formulations and containing different amounts of free zinc.

Recent research indicates that early treatment of common cold with zinc lozenges may shorten the duration of common cold symptoms by several days. However, there are several clinical trials that have reported that zinc lozenges are no more effective than placebo medicines. The difference between clinical trials may be related to different formulations of zinc lozenge.

ANTIOXIDANTS

Natural disinfectants can cause symptoms

The white blood cells which ingest viruses and bacteria use powerful disinfectants (oxidising agents) to destroy the infective agents. This oxidising activity, can be overdone and can also damage neighbouring cells and cause inflammation. This inflammation results in severe common cold symptoms.

Antioxidants can help alleviate symptoms

Antioxidant compounds such as ascorbate from vitamin C and components of garlic such as Allicin can have a beneficial effect by limiting the damage caused by excess oxidising agents. There are numerous garlic preparations available but Allicin is present only in garlic powder and fresh garlic but not in garlic oil or macerated garlic. Large doses of Vitamin C (1-2 grammes a day) are required in order to provide any useful antioxidant activity and it is unlikely that the small doses of vitamin C in many common cold medications provide any real benefit to the patient.

Daily vitamin C does not prevent colds!

The double Nobel laureate Linus Pauling was a great proponent of daily intake of vitamin C as a means of preventing infection. However, only a very small minority of the population in the West are likely to have any defficency of vitamin C in their diet and it seems unlikely that regular prophylactic intake of vitamin C is going to provide any real benefit to the vast majority of the population .

HOMEOPATHY

The main principles of homeopathy are; that a substance that causes symptoms in a healthy person can be used to treat those symptoms when they occur in a sick person; that diluting and banging the homeopathic medicine increases its curative powers and avoids unwanted side effects; and that homeopathy treats the whole person, and not just the illness. Most scientists dismiss hoemeopathy as a placebo effect.

Alternative medicines are safe!

Patients often use alternative medicines because they assume that 'natural' medicines are safer and have fewer side effects than conventional medicines. The prevalence of adverse effects associated with alternative medicines appears to be low, and is probably lower than comparable medicines used in conventional medicine. There is some cause for concern about heavy metal contamination of alternative medicines which are not marketed in a controlled way, but if the patient uses regularly marketed alternative medicines there appears to be no major safety issues in the use of alternative medicines.

Some useful references

1. Jonas W B, Safety in complementary medicne, in Complementary medicine, an objective appraisal, E. Ernst, Editor. 1996, Butterworth-Heinemann: Oxford. p. 126-149.

2. Lorber B (1996) The Common Cold. Journal Of General Internal Medicine 11: 229-236.

3. Eccles R (1994) Menthol and related cooling compounds. Journal of Pharmacy and Pharmacology 46: 618-630.

4. Naganawa R, Iwata N, Ishikawa K, Fukuda H, Fujino T, Suzuki A (1996) Inhibition Of Microbial-Growth By Ajoene, a Sulfur-Containing Compound Derived From Garlic. Applied and Environmental Microbiology 62: 4238-4242.

5. Parnham M J (1996) Benefit-Risk Assessment Of the Squeezed Sap Of the Purple Coneflower (Echinacea-Purpurea) For Long-Term Oral Immunostimulation. Phytomedicine 3: 95-102.

6. Korant B D, Kauer J C, Butterworth B E (1974) Zinc ions inhibit replication of rhinoviruses. Nature 248: 588-590.

7. Novick S G, Godfrey J C, Godfrey N J, Wilder H R (1996) How Does Zinc Modify the Common Cold - Clinical Observations and Implications Regarding Mechanisms Of Action. Medical Hypotheses 46: 295-302.

8. Beck F W J, Prasad A S, Kaplan J, Fitzgerald J T, Brewer G J (1997) Changes in cytokine production and T cell subpopulations in experimentally induced zinc-deficient humans. American Journal Of Physiology-Endocrinology and Metabolism 35: E1002-E1007.

9. Eby G A, Davis D R, Halcomb W W (1984) Reduction in duration of common cold by zinc gluconate lozenges in a double blind study. Antimicrobial agents and chemotherapy 25: 20-24.

10. Mossad S B, Macknin M L, Medendorp S V, Mason P (1996) Zinc gluconate lozenges for treating the common cold. A randomized, double blind , placebo controlled study. Annals of Internal Medicine 125: 81-88.

11. Prasad K, Laxdal V A, Yu M, Raney B L (1995) Antioxidant Activity Of Allicin, an Active Principle In Garlic. Molecular and Cellular Biochemistry 148: 183-189.

12. Hemila H (1997) Vitamin C intake and susceptibility to the common cold. British Journal Of Nutrition 77: 59-72.

13. Kleijnen J, Knipschild P, Terriet G (1991) Clinical-Trials Of Homeopathy. British Medical Journal 302: 316-323.

14. Ferley J P, Zmirou D, Dadhemar D, Balducci F (1989) A Controlled Evaluation Of a Homeopathic Preparation In the Treatment Of Influenza-Like Syndromes. British Journal Of Clinical Pharmacology 27: 329-335.

15. Berger A. What does zinc do. BMJ 2002; 325:1062.

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