Elderberry for the Flu

A 2004 study found that elderberry syrup significantly reduced duration and severity of illness compared to placebo in people with laboratory confirmed influenza virus. The elderberry syrup was initiated within 48 hours of symptom onset and taken four times per day for 5 days. It is thought that elderberry prevents the adhesion of the influenza virus to cell receptors.

Other studies have not found the same efficacy for elderberry in people with other viruses. Raw elderberries and other parts of the elder tree contain poisonous cyanide-producing substances. Cooking eliminates these poisonous substances.

Zakay-Rones Z, Thom E, Wollan T, Wadstein J. Randomized study of the efficacy and safety of oral elderberry extract in the treatment of influenza A and B virus infections. J Int Med Res. 2004 Mar-Apr;32(2):132-40. doi: 10.1177/147323000403200205. PMID: 15080016.

Zakay-Rones Z, Varsano N, Zlotnik M, Manor O, Regev L, Schlesinger M, Mumcuoglu M. Inhibition of several strains of influenza virus in vitro and reduction of symptoms by an elderberry extract (Sambucus nigra L.) during an outbreak of influenza B Panama. J Altern Complement Med. 1995 Winter;1(4):361-9. doi: 10.1089/acm.1995.1.361. PMID: 9395631.