Clinical trials have used water or alcohol extracts of tulsi leaves most consistently, although all parts of the plant have been used in a variety of ways. The types of active compounds in tulsi can vary depending on the part of the plant used, the extraction methods, and the growing and harvesting conditions.^[1]

Studies have reported beneficial effects of tulsi (aqueous leaf extract) taken orally at dosages ranging from 300 mg to 3,000 mg daily. Currently, there’s not enough evidence to determine what an optimal dose or formulation might be, and this information has often been poorly defined in studies. For example, studies providing “30 drops of tulsi extract” with no further details are not uncommon.^[2]

For oral use in periodontal disease, gels or mouth rinses containing 2% to 4% tulsi appear effective.^[3][4]