A randomized controlled clinical trial of hospitalized Covid-19 patients found that adding “Brazilian green propolis” as an adjunct treatment to standard care had two statistically significant benefits:
* reduction in length of hospital stay
* strong reduction in risk of injury to kidneys

Silveira, Marcelo Augusto Duarte, et al. “Efficacy of Brazilian Green Propolis (EPP-AF) as an adjunct treatment for hospitalized COVID-19 patients: a randomized, controlled clinical trial.” Biomedicine & Pharmacotherapy (2021): 111526. Study Link

The study was done in Brazil. Hospitalized Covid-19 patients were divided into three groups of about 40 patients each. One group was the control; another received 400 mg/day green propolis; a third group received 800 mg/day of green propolis. Statistically significant reduction in number of days in hospital was found for both treatment groups. The average number of days was 12.6 for the control, 9.5 for the 400 mg/d Tx group; 8.2 for the 800 mg/d Tx group. The range of days was about plus or minus 2 days for all groups (approx.). That is a reduction in 3 or more days of hospital stay, and for the 800 mg group about a 31% reduction.

Consider the importance of that value. Hospital Covid-19 units are filled and over-flowing in many places. Reducing the length of hospital stay by 30% would open up many more beds for new patients. That benefit alone is worth the time, money, and effort of further study of this adjunct treatment.

Please understand that Green Propolis is not a treatment for Covid-19 by itself. It is only useful along with the other treatments, as a helper. Green Propolis is not the main way to get better from Covid-19. But it is helpful when used alongside other mainline treatments. It is not the main course, but a side dish.

The other benefit was a reduction in risk of Acute Kidney Injury. Only the 800 mg Tx group had a statistically significant result (p=0.048), but the risk ratio was 0.18. That indicates an 82% reduction in risk of kidney injury for this group of hospitalized Covid-19 patients given 800 mg/day of green propolis.

The end point of renal replacement therapy (dialysis and similar treatments) was not statistically significant. However, given the above reduction of kidney injury, and the absolute numbers of no one in the 800 mg Tx group needing dialysis versus 7 in the control group, this end point should be examined in a study with more participants.

The need for invasive ventilation (after the patients were randomized) showed borderline statistical significance for the 400 mg Tx group. The control group had 19.5% of patients needing invasive ventilation versus 5.3% for the 400 mg Tx group (p=0.065), and 7.3% for the 800 mg Tx group (p=0.107). This benefit is worth examining further in a larger study.

The study authors concluded benefits in reducing hospital stay, as well as reduced kidney damage associated with COVID-19 (for the 800 mg/day Tx group). They stated: “Propolis was safe and effective as an adjunct treatment.”

Which Components of Propolis?

A different type of study, this one using computer analysis of viral proteins versus the components of Brazilian Green Propolis, determined that 22 different propolis compounds are inhibitors of Covid-19 viral proteins. SARS-CoV-2 is the official name of the Coronavirus, which causes Covid-19.

Harisna, Azza H., et al. “In silico investigation of potential inhibitors to main protease and spike protein of SARS-CoV-2 in propolis.” Biochemistry and Biophysics Reports (2021): 100969. Study Link

Of the 22 compounds found in Propolis, 18 had binding affinities for the Main protease of Covid-19 and a slightly different set of 18 (out of the same 22) compounds had binding affinities for the Spike protein over 6.0 kcal/mol. This set of different compounds, each of which has beneficial effects in slowing down the virus might explain the benefits in the above discussed clinical study.


Brazilian Green Propolis is a generally safe over-the-counter health supplement, which may have benefits for Covid-19 patients. Taking this type of propolis in advance of becoming ill might be more beneficial, as it would give time for the compounds to build up on one’s body.

Note that some persons might be allergic to propolis. If you are allergic to propolis or to honey or to any related food or supplement, then do NOT take propolis supplements.

The above two studies are very preliminary. A larger study needs to be done, and there is not as much support from traditional medical authorities and from the media for natural products as treatments for Covid-19. Until we have more studies, especially those with a larger number of patients, no definitive conclusions can be drawn. However, this treatment is deserves further study.

Ronald L. Conte Jr.
“an author, not a doctor”