In brief: Hibiscus herbal infusion (Hibiscus sabdariffa), also known as karkadé or bissap, is a ruby-red, tangy drink rich in anthocyanins. Several studies suggest a moderate effect on blood pressure. Use 1 tablespoon of dried flowers per 250 ml cup, steeped for 8 to 10 minutes at 95 °C. Precautions: avoid if you have low blood pressure or are pregnant.
Hibiscus is one of the most widely consumed flowers in the world as a herbal infusion. In Mexico (agua de jamaica), Egypt (karkadé) and West Africa (bissap), it is a national drink. Its properties have been the subject of several serious clinical studies, notably regarding blood pressure. This page covers its composition, documented uses, preparation, and the precautions worth knowing.
Composition and documented properties
The dried calyces of Hibiscus sabdariffa contain:
- Anthocyanins (delphinidin, cyanidin): red pigments with well-documented antioxidant properties.
- Hibiscic acid and organic acids: responsible for the characteristic tangy flavour.
- Various polyphenols: flavonoids, phenolic acids.
- Mucilages: a mild soothing effect.
The best-documented effect concerns blood pressure. A meta-analysis published in the Journal of Hypertension observed a modest reduction in systolic and diastolic blood pressure among people who consumed hibiscus regularly. The effect is moderate, cannot replace antihypertensive treatment in any way, but is consistent.
How to brew a good hibiscus herbal infusion
- Amount: 1 tablespoon (2 g) of dried calyces per 250 ml cup.
- Water: bring to a gentle simmer (95 °C).
- Time: 8 to 10 minutes, covering the cup to preserve the anthocyanins.
- Straining: strain through a fine sieve. You can add honey to soften the natural acidity.
- Cold version: the traditional bissap recipe. Steep 3 tablespoons in 1 litre of cold water for 6 hours, strain, add cane sugar or honey, and serve over ice with fresh mint.
- Frequency: 2 to 3 cups per day over a 4 to 6-week course for blood pressure effects. For everyday enjoyment, there is no particular limit at a sensible dose.
Classic pairings
- Hibiscus + rosehip: a blend especially rich in vitamin C and antioxidants.
- Hibiscus + mint: the West African bissap version, traditional and refreshing.
- Hibiscus + cinnamon + ginger: a warming winter version, like mulled wine without the alcohol.
- Hibiscus + Rooibos: softens the acidity, perfect for children.
- Hibiscus + red berries: the base of many red berry herbal infusions.
Precautions and contraindications
- Low blood pressure: the hypotensive effect may be problematic for those who already have low blood pressure. Avoid or seek advice.
- Antihypertensive medication: a possible additive effect. Let your doctor know about your consumption.
- Pregnancy: not recommended. Hibiscus has traditionally been used for its emmenagogic effects (inducing menstruation), and animal studies suggest a possible effect on the uterus.
- Breastfeeding: as a precaution, best avoided.
- Diuretics: a mild diuretic effect is possible; worth monitoring.
- Medications: possible interactions with certain treatments (paracetamol, chloroquine). Mention your consumption to your doctor.
- Tooth enamel: the acidity can erode enamel with very frequent consumption. Drink through a straw during a prolonged course.
- Diabetes under treatment: a mild hypoglycaemic effect is possible.
Disclaimer: the information in this article is for educational purposes only and does not replace medical advice. High blood pressure requires medical monitoring and appropriate treatment. Hibiscus herbal infusion can support a healthy lifestyle, but never replace one.
Sources: Serban C. et al., Journal of Hypertension, meta-analysis on hibiscus and blood pressure (PMID:24818816) · McKay D.L. et al., Journal of Nutrition on hibiscus and blood pressure · ANSES, recommendations on plants in infusion · WHO monograph on selected medicinal plants Vol. 4.
Written by
Julien Huot, founder of Thés & Traditions. Tea selector since 2016, trained in tasting and passionate about sharing the cultures of tea and botanical infusions.
Published on 14 August 2019 · Updated on 21 May 2026
Frequently asked questions
- Several studies have observed a moderate effect on systolic and diastolic blood pressure with regular consumption (2 to 3 cups per day over several weeks). The effect does not replace antihypertensive treatment, but it is consistent and well-documented.
- Yes, these are three names for the same drink, made from the dried flowers of Hibiscus sabdariffa. Bissap is the West African name, karkadé the Egyptian one.
- No, it is not recommended during pregnancy due to its traditional emmenagogic effects and animal data suggesting a uterine effect.
- 2 to 3 cups per day for blood pressure effects. For everyday enjoyment, up to 4 cups is reasonable for an adult with no contraindications.
Going further
To deepen your infusion rituals, explore our guide to red berry herbal infusions, of which hibiscus is often the base, or our cranberry guide for tangy berries. To put it into practice, browse our organic range.