Herb library · Spice · Ocimum gratissimum (formerly also O. viride)
Scent leaf
A tall basil eaten as a salad herb and long used for fevers across West Africa. In two small trials, a mouth rinse made with it reduced dental plaque, though less than the standard rinse chlorhexidine in one of them.
Traditional use
Writing in 1915, J. H. Holland records it as Efirin in Lagos, Aramoho in Benin and Ntion among the Efik of Old Calabar, where it was also eaten as a salad, and in Sierra Leone as the fever plant, sold in bundles in the markets. Most of the uses he lists are for fevers; at Aburi in the Gold Coast the leaves were boiled with peppers for dysentery and fevers. A 2021 review lists its traditional uses today for diabetes, diarrhea, pain, anemia and infections.
What studies show
- Limited
Dental plaque and gum inflammation: in a 3-month trial with 10 people per group, a scent-leaf mouth rinse reduced plaque and gum bleeding about as much as chlorhexidine. In a 3-day trial in 15 volunteers, a 10% scent-leaf rinse held back new plaque, but less well than chlorhexidine. Both trials were very small.
- Insufficient
Blood sugar, diarrhea, infections and other traditional uses: laboratory and animal studies only. A 2021 review says trials in people are still needed to set safe and effective doses.
Be careful of
Cautions
- InteractionIn a laboratory study, scent-leaf extract blocked several liver enzymes (CYP1A2, 2C8, 2C9 and 2C19) that clear many drugs, which could raise their levels. This has not been tested in people; the authors advise caution for anyone taking prescription medicines with it.
- NoteAs a cooking herb it is widely eaten; the safety of concentrated extracts has not been studied in people.
- PregnancyThere is no safety information on extracts in pregnancy or breastfeeding.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“The plant has been recommended for driving away mosquitos, and it aroused considerable interest a few years ago; but experiments have proved that the plant is of no value for the purpose.”
“Various medicinal uses are attributed to the plant, but chiefly as a febrifuge (see Shipley in Nature, seq., Cole, Journ. Soc. Arts, liii. 1905, p. 1068, Holmes, Pharm. Journ. [3] viii. 1878, p. 563), and it is used as salad, Old Calabar.”
Sources
- Clinical effect of a mouth rinse containing Ocimum gratissimum on plaque and gingivitis control (J Contemp Dent Pract, 2011) (opens in a new tab) · NIH · read September 25, 2026
- Effect of Ocimum gratissimum in Mouthrinses on De Novo Plaque Formation. A Randomized Clinical Trial (Braz Dent J, 2016) (opens in a new tab) · NIH · read September 25, 2026
- A review on the traditional uses, phytochemistry, and pharmacological activities of clove basil (Ocimum gratissimum L.) (Heliyon, 2021) (opens in a new tab) · NIH · read September 25, 2026
- Cytochrome P450 Enzyme Inhibition and Herb-Drug Interaction Potential of Medicinal Plant Extracts Used for Management of Diabetes in Nigeria (Eur J Drug Metab Pharmacokinet, 2021) (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.