Dosage and Side Effects
There is no accepted or uniform dosage for hibiscus preparation. Studies show that drinking hibiscus tea in moderate quantities is safe. The safety of other preparations, like powders, capsules, and extracts, is not well known. Some studies show that consistent use of high doses of hibiscus extract may result in liver injury. Hibiscus may also interact with certain drugs. Doctors advise people who are pregnant or breastfeeding to not drink hibiscus tea or take hibiscus supplements due to an absence of evidence on the safety of the plant in these populations.
Taking hibiscus regularly may help reduce blood pressure. People with high blood pressure or diabetes who are taking drugs should contact their doctors before trying hibiscus.