The efficacy of Hibiscus sabdariffa (rosella) in essential hypertension: A systematic review of clinical trials

Hypertension is a common condition in Western nations and is associated with significant morbidity. Hibiscus sabdariffa (rosella) has a long history of traditional use across multiple continents and cultures for a number of chronic illnesses, including hypertension.

Method: The effectiveness of Hibiscus sabdariffa for the treatment of hypertension was assessed via a systematic review of human clinical trials. A computer-based search and data abstraction was done on 29 October 2015 using the following databases: AMED, Academic Search Prem, CINAHL, Greenfile, Healthsource, Medline, PsychArticles, Psychology and Behavioural Sciences Collection, PsycINFO, SPORTDiscus, EMBASE and COCHRANE.

Results: Ten papers were found that met the inclusion criteria. Heterogeneity in trial design precluded combination of the results. All papers found a significant decrease in systolic blood pressure (SBP) in the rosella groups. The decrease in SBP ranged from 6.3-31.9 mm Hg in individual trials. The decrease in diastolic blood pressure (DBP) was significant in nine of the ten trials and ranged from 1.1-19.7 mm Hg. In comparative trials, a standardised extract of rosella (9.62 mg of total anthocyanins/dose/day) appeared to be as effective as captopril and hydrochlorothiazide, but not as effective as lisinopril.

Conclusion: Rosella appears to be a safe and well-tolerated treatment option, which may have a place in the treatment of mild-to-moderate essential hypertension. Data suggests that it may provide comparable effectiveness to some pharmaceutical antihypertensive medications. Further research should focus on dose and duration of treatment, interactions with medications and quality of starting material.