Homeopathy uses highly diluted medicines on the basis of “like cures like.” The best evidence-based homeopathic medicine for flu is Oscillococcinum^®. Licensed in Canada, the US, and many European countries, it is widely available and seems safe and effective for the treatment of influenza and influenza-like syndromes. A Cochrane Review of Oscillococcinum and similar medicines included seven trials with a total of 2,265 participants concluding the evidence that it shortens the duration of flu is promising, and recommended further research.¹ Oscillococcinum is widely available in drug stores and pharmacies; the recommended posology is one tube dose, dry on the tongue, three times daily.

Two other systematic reviews conclude that homeopathy generally is effective in upper respiratory tract infections including sinusitis and acute otitis media^{2, 3}, and there is anecdotal evidence of the effectiveness of homeopathy from the 1918-19 pandemic.^{4, 5} Homeopathy appears very safe: a systematic review concluded that homeopathic medicines may provoke adverse effects, but these are generally mild and transient.⁶ In two studies, adverse reactions were observed in approximately 2.7 percent of the patients^{7, 8}. Prescribing indications for individualized homeopathic medicines commonly used in flu are summarized in the box.

Prescribing criteria for some homeopathic medicines commonly prescribed for flu. The recommended posology for all is 5 pellets of the 30c potency every 4 hours. If there is improvement continue as long as symptoms persist. If there is no improvement after 4 doses, or if the pattern of symptoms shifts, change to another medicine which most closely matches the individual’s symptoms.

Herbal medicines for flu

Several herbal medicines have shown promise in clinical trials for seasonal epidemic influenza. A recent systematic review of complementary medicines for treatment of influenza⁹ identified positive studies of standardized herbal extracts of Panax quinquefolium (American ginseng root), Sambucus nigra (elderberry fruit), and the herbal combination Kan Jang (a combination of Andrographis paniculata (Andrographis root) and Eleutherococcus senticosus (Siberian ginseng root). However, there were methodological problems with the studies.

Other widely used herbs are effective in treating viral upper respiratory infections (URTI’s), but have not specifically been tested for influenza, although since they appear to act by stimulation of non-specific immune responses such as macrophage phagocytosis, it is possible that they may be effective. They include Echinacea species, for which systematic reviews of randomised controlled trials indicate a possible effect in treatment, although not prevention, of viral URTI¹⁰. The evidence is limited by heterogeneity in the plant species used (E.purpurea or angustifolia), the plant part (e.g. root or aerial parts), the dose, and type of extract. A recent randomized controlled trial of an extract of Pelargonium sidoides (the root of a southern African species traditionally used for respiratory conditions) in common cold showed a clinically relevant reduction in symptoms and significantly higher chance of recovery at five days¹¹. Another systematic review of four studies indicates a beneficial effect of a standardized Androgaphis paniculata extract in the treatment of viral URTI¹².

Safety of herbs

Adverse effects are usually mild and transient for these herbal extracts and comparable to placebo in clinical trials. Serious adverse effects have not been reported for P.quinquefolium, A.paniculata, S.nigra or E.senticosus. A prospective observational study of over 50,000 patients treated with Echinacea and other Compositae species showed no serious adverse effects¹³, although there is a single case report of anaphylaxis¹⁴. Another concern with herbal medicines is herb-drug interactions. No case reports exist for any of the herbs above, although because of in vitro effects on coagulation parameters and cytochrome p450 enzymes, serious interactions with warfarin and other drugs are possible. There is no evidence to suggest that these herbs will interact with NAIs.

In general, these herbs are not recommended in pregnancy, lactation, and in young children due to lack of sufficient safety data.

Conclusion

Although the evidence is limited, there is positive evidence for homeopathy and herbal extracts in influenza and viral URTI. To date there is no evidence of their effectiveness for novel H1N1 influenza. They are generally safe and may provide useful treatment options, when integrated with conventional care.

List of Herbs

Source: alive Web Exclusive, November 2009