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Herb library · Herb · Hibiscus sabdariffa

Hibiscus (roselle)

The dried red calyces of roselle make a tart drink across West Africa, the Caribbean and Latin America. The blood pressure evidence is mixed: a 2022 meta-analysis found a modest drop, while a 2021 Cochrane review found too little good evidence to judge.

Traditional use

Drunk hot or cold as zobo in Nigeria, bissap in Senegal, karkadi in Sudan and sorrel in Jamaica, and described by Cochrane's reviewers as used both as a thirst-quenching drink and for medicinal purposes. In some cultures it is given to nursing mothers to increase milk supply.

Traditional energetics

What studies show

  • Limited

    Blood pressure: a 2022 meta-analysis of 17 trials found systolic blood pressure about 7 mmHg lower with hibiscus than with placebo, with the largest drops in people whose blood pressure started high. The trials disagreed with each other a great deal, and the authors call for more work on dose and duration.

  • Insufficient

    High blood pressure specifically: a 2021 Cochrane review, applying stricter entry rules, found only one qualifying trial (60 people) and rated the evidence insufficient and of very low certainty. It is not a substitute for prescribed blood pressure medicine.

  • Limited

    Cholesterol: the same 2022 meta-analysis found LDL cholesterol about 7 mg/dL lower than with other teas or placebo, a result right at the edge of statistical significance.

  • Insufficient

    Milk supply: LactMed reports no scientifically valid clinical trials supporting its use to increase breast milk.

Be careful of

Cautions

  • InteractionIt can change how the body handles some medicines. In small studies of healthy volunteers, a Sudanese hibiscus drink sharply lowered blood levels of the malaria medicine chloroquine, and zobo sped up the clearance of acetaminophen. Take medicines with water, not with a hibiscus drink.
  • ConditionIf you take blood pressure medicine, tell your clinician before drinking hibiscus daily, since studies measured lower blood pressure with it, and never use it in place of a prescribed medicine.
  • AllergyAllergic reactions are possible, including cross-reactions with other plants of the mallow family, such as marshmallow and ambrette (LactMed).
  • PregnancyNo data exist on its passage into breast milk or its safety for nursing mothers or infants (LactMed). As a food it is generally recognized as safe by the FDA; concentrated extracts are a different matter.
  • Ask a clinicianTalk with a clinician or pharmacist before using hibiscus regularly if you take prescription medicines, have a medical condition, or are pregnant or breastfeeding.

From the old books

What herbals and dispensaries of the past printed. History, in their words.

“the decoction of them, sweetned and fermented, is what people commonly call, Sorrel Cool-drink, in America: it is a small diluting liquor, that is much used in all our sugar-colonies, and reckoned very refreshing in those sultry climates.”
Patrick Browne, The Civil and Natural History of Jamaica (1756), p. 285. See the page of The Civil and Natural History of Jamaica, p. 285 (opens in a new tab) · Read the full passage from The Civil and Natural History of Jamaica, p. 285
“Out of the French Sorrel, in this and other places, which came from Surinam, is made a fine cooling Conserve and Syrup.”
Hans Sloane, A Voyage to the Islands Madera, Barbados, Nieves, S. Christophers and Jamaica (1707), vol. 1, p. lxii. See the page of A Voyage to the Islands Madera, Barbados, Nieves, S. Christophers and Jamaica, vol. 1, p. lxii (opens in a new tab) · Read the full passage from A Voyage to the Islands Madera, Barbados, Nieves, S. Christophers and Jamaica, vol. 1, p. lxii

Sources

  1. Roselle for hypertension in adults (Cochrane Database Syst Rev, 2021) — PubMed record (opens in a new tab) · NIH · read September 22, 2026
  2. A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers (Nutr Rev, 2022) — PubMed record (opens in a new tab) · NIH · read September 22, 2026
  3. Hibiscus — Drugs and Lactation Database (LactMed) (opens in a new tab) · NIH · read September 22, 2026
  4. Significant reduction in chloroquine bioavailability following coadministration with the Sudanese beverages Aradaib, Karkadi and Lemon (J Antimicrob Chemother, 1994) (opens in a new tab) · NIH · read September 22, 2026
  5. Effect of zobo drink (Hibiscus sabdariffa water extract) on the pharmacokinetics of acetaminophen in human volunteers (Eur J Drug Metab Pharmacokinet, 2004) (opens in a new tab) · NIH · read September 22, 2026

Reviewed September 22, 2026.