Fadogia agrestis is best known for its purported aphrodisiac effects. According to one rodent study, supplementation with Fadogia agrestis for 5 days led to remarkable increases in testosterone (2-fold with 18 mg/kg, 3-fold with 50 mg/kg, and 6-fold with 100 mg/kg) and enhanced libido.[1] Based on the magnitude of its benefit in rodents, it appears to be one of the more potent herbs for increasing both testosterone and libido, with the effect sizes being greater than those of Spilanthes acmella.[2][1] In another rodent study, supplementation with Fadogia agrestis increased testicular weight by 11–15%.[3]
Limited animal evidence supports the pro-erectile properties of this herb, but an associated increase in ejaculation latency (time to ejaculation) has also been noted. This is a fairly rare property among aphrodisiacs, as they usually reduce ejaculation latency.[1]
A single in vitro study isolated glycosides of Fadogia agrestis roots and found that some of them possessed inhibitory effects on certain parasites and bacteria, and displayed mild antimalarial activity.[4] Another in vitro study found that Fadogia agrestis displayed antispasmodic properties.[5]