Homoeopathic Oscillococcinum for preventing and treating influenza and influenza-like syndromes

  • Review
  • Intervention


  • AJ Vickers,

  • C Smith

Dr Andrew Vickers, Assistant Attending Research Methodologist, Integrative Medicine Service, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY, 10021, USA. vickersa@mskcc.org.



Influenza is a highly infectious viral disease that is particularly common in the winter months. Oscillococcinum is a patented, commercially available homoeopathic medicine. The rationale for its use in influenza comes from the homoeopathic principle of 'let like be cured by like'. The medicine is manufactured from wild duck heart and liver, which are said to be reservoirs for influenza viruses.


To determine whether homoeopathic Oscillococcinum or similar medicines are more effective than placebo in the prevention and treatment of influenza and influenza-like syndromes.

Search strategy

The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library issue 2, 2003); MEDLINE (January 1966 to June 2003) and EMBASE (1980 to June 2003) were searched, using the term "homeopathy" with "influenza", "respiratory tract", "infection", "cough", "virus" and "fever". The manufacturers of Oscillococcinum were contacted for information.

Selection criteria

Placebo-controlled trials of Oscillococcinum or homeopathically-prepared influenza virus, influenza vaccine or avian liver in the prevention and treatment of influenza and influenza-like syndromes.

Data collection and analysis

Two reviewers extracted data and assessed methodological quality independently.

Main results

Seven studies were included in the review, three prevention trials (n = 2265) and four treatment trials (n = 1194). Only for two studies was there sufficient information to complete data extraction fully. There was no evidence that homoeopathic treatment can prevent influenza-like syndrome (relative risk 0.64, 95% confidence interval 0.28 to 1.43). Oscillococcinum treatment reduced length of influenza illness by 0.28 days (95% confidence interval 0.50 to 0.06). Oscillococcinum also increased the chance of a patient considering treatment effective (relative risk 1.08; 95% CI 1.17, 1).

Authors' conclusions

Though promising, the data are not strong enough to make a general recommendation to use Oscillococcinum for first-line treatment of influenza and influenza-like syndrome. Further research is warranted but required sample sizes are large. Current evidence does not support a preventative effect of Oscillococcinum-like homeopathic medicines in influenza and influenza-like syndromes.

Plain language summary

Plain language summary

Homoeopathic Oscillococcinum does not prevent influenza, but probably shortens the length of the illness

Influenza (the flu) is a highly infectious disease caused by viruses. Other than treatments for complications (such as pneumonia), conventional medical treatment is bed rest. Homeopathy is a system based on "curing like with like", often using highly diluted substances. Oscillococcinum is a homoeopathic preparation manufactured from wild duck heart and liver (common sources of influenza). It is claimed that Oscillococcinum (or similar homeopathic medicines) can be taken regularly over the winter months to prevent flu, or as a treatment. The review found that trials do not show that it can prevent flu. Taking it once you have flu probably shortens the illness, but more research is needed.