hibiscus

Common names
Hibiscus, roselle, karkade, sour tea
Botanical names
Hibiscus sabdariffa, H. rosa
Parts used and where grownMembers of the Malvaceae family, various species of hibiscus are shrubs found practically around the globe. The flower of hibiscus is the part used as medicine. The most widely known and best-studied species tend to be annuals from the tropics, such as the two that are focused on here. There are, however, hardy perennial species that survive in colder climates. Another hibiscus not discussed here is Hibiscus esculenta, or okra.
Hibiscus has been used in connection with the following conditions (refer to the individual health concern for complete information):
Science Ratings - Health Concerns** - Hypertension
** - Lice
* - Fever
* - Type 1 diabetes
* - Type 2 diabetes
*** - Reliable and relatively consistent scientific data showing a substantial health benefit.
** - Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
* - For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support and/or minimal health benefit.
Historical or traditional use (may or may not be supported by scientific studies)
Teas made from hibiscus flowers and, occasionally, leaves are a very common beverage in tropical regions where they grow. The cool, astringent, acidic flavor is widely recognized and has made it a staple of “zinger” type teas in the United States. All parts of hibiscus plants are used traditionally. Due to their soothing (demulcent) and astringent properties, the flowers and leaves have been traditionally used to treat conditions such as cancer and gallbladder attacks, to lower blood pressure, to relieve dry coughs, and topically to treat skin afflictions.1 The root has been used as a tonic. The stems yield fibers that can be used to make rope or burlap.
Active constituentsThe flowers contain substantial quantities of flavonoids and proanthocyanidins,2 which are associated with antioxidant, fever-reducing (antipyretic), pain-relieving (analgesic), and spasm-inhibiting (spasmolytic) activities.3 4 Of the many polysaccharides, the acidic polysaccharides show the most interesting properties. For example, they stimulate specialized skin cells which would presumably promote wound healing and these polysaccharides are also immune-modulating.5 6 There is also a high concentration (15 to 30%) of simple organic acids such as citric and malic acids.7
Complex extracts of hibiscus have shown other properties in the test tube and in animal studies, such as reducing skin cancer promoted by ultraviolet light, inhibiting herpes simplex virus, and lowering cholesterol levels.8 9 10 A variety of studies have looked at the potential use of hibiscus for male and female fertility regulation with mixed results.11 12 13
How much is usually taken?Hibiscus is usually taken as tea. Clinical trials have used 1 to 2 tsp (3 to 6 grams) of dried flower infused in to 1 cup (250 ml) three times per day.14 One study used 500 ml of tea once a day before breakfast.15
Are there any side effects or interactions?There are no known side effects from reasonable amounts of hibiscus.
Drug InteractionsCertain medicines interact with hibiscus: Some interactions may increase the need for hibiscus (+), other interactions may be negative (-) and indicate hibiscus should not be taken without first speaking with your physician or pharmacist, others may require further explanation (?). Refer to the individual drug article for specific details about an interaction.
Note: The following list only includes the generic or class name of a medicine. To find a specific brand name, use the Medicines index.
Acetaminophen (-)Acetaminophen with Codeine (-)Hydrocodone with Acetaminophen (-)