Elderberry may ease viral respiratory symptoms

Integrative Medicine

Many dietary supplements and homeopathic products have been used to prevent or treat viral infections of the respiratory tract, including ascorbic acid, zinc, echinacea, andrographis, and ginseng. Sambucus nigra, a member of the Adoxacea family and commonly known as elderberry, has been used recently for respiratory tract viral infections because of its immunomodulatory properties. 

Elderberry’s antiviral activity may be due to its high concentration of flavonoids, specifically the anthocyanins cyanidin 3-glucoside and cyanidin 3-sambubioside, which are anti-inflammatory agents. Some elderberry extracts have shown in vitro antibacterial activity against some gram-positive and gram-negative respiratory pathogens. Elderberry also contains many vitamins. Although elderberry has been used by many patients, clinical trials evaluating its efficacy in humans are limited.

Elderberry vs. placebo

A trial examined 60 patients presenting with a temperature over 38°C and at least one respiratory symptom consistent with influenza that started within the past 48 hours. Participants were randomized to receive either 15 mL of a standardized 38% elderberry extract or an identical placebo syrup four times daily for 5 days. Eligible participants recorded their symptoms on a visual analogue scale four times daily during the treatment period and twice daily for 5 days after the end of the treatment period. Symptoms were given a severity score ranging from 0 (caused no problems) to 10 (caused pronounced problems) in the following categories: aches and pains, degree of coughing, quality of sleep, mucus discharge, and nasal congestion.

Patients receiving the elderberry extract showed pronounced symptom improvement after 3 to 4 days, whereas patients receiving the placebo showed similar improvement after 7 to 8 days. Adverse reactions were not reported.1

Recently, a combination herbal preparation containing elderberry was evaluated for treating rhinosinusitis, a condition that is generally self-limited,with symptoms improving after 7 to 11 days.2 A dry herbal extract of elder flower (Sambuci flos), gentian root (Gentianae radix), primula flower (Primulae flos), sorrel herb (Rumicis herba), and verbena herb (Verbenae herba) was prepared in a ratio of 3:1:3:3:3. This extract was given in a dosage of 160 mg three times daily for 15 days to 194 patients diagnosed with rhinosinusitis by ultrasonography of their maxillary sinuses. 

Participants were required to have sudden onset and less than 3 days’ duration of at least three of the following symptoms: rhinorrhea or anterior discharge, postnasal drip, nasal congestion, headache, or facial pain or pressure. Symptom severity was assessed on a 15-point scale, and eligible patients were required to rank a Major Symptom Score (MSS) between 8 and 12 points, with greater numbers indicating greater severity. Placebo extract was given in the same dosage to 191 patients meeting the same criteria. 

Patients recorded symptom severity and intake of their study medications on diary cards. The mean investigator–assessed primary endpoint on day 14 of treatment was significantly lower in the treatment group than in the placebo group. Secondary endpoints included rate of patients considered to be cured, with an MSS less than 1, which was 48.4% in the treatment group and 35.8% in the placebo group. About 15% of patients in the active treatment and 24% of individuals receiving placebo demonstrated a lack of effect from the blend.

What to tell patients

Hand hygiene and vaccination remain the most effective methods available to prevent infections such as influenza. Antiviral agents such as oseltamivir may be used to treat patients with influenza, as the drugs shorten the duration of symptoms when taken within 48 hours of symptom onset. Early reporting of respiratory symptoms to a provider may help expand treatment options and limit symptom duration. 

Elderberry extract may help alleviate viral symptoms more quickly, but evidence is limited. Pharmacists should recommend standardized products such as the original formulation of sambucol over homeopathic preparations.                   

References

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;32:132–40. 

Jund R, Mondigler M, Steindl H, et al. Clinical efficacy of a dry extract of five herbal drugs in acute viral rhinosinusitis. Rhinology. 2012;50:417–26.