Tortuosamine is an alkaloid found in Sceletium tortuosum. Tortuosamine is a Serotonin reuptake inhibitor (SRI). Tortuosamine is a MAO-B inhibitor, that means it blocks the enzyme that breaks down dopamine in the brain resulting in increased dopamine levels when consumed, either orally, smoked, or snorted. The 3 other main alkaloids found in Sceletium tortuosum are, Mesembrine, Mesembrenone, and Mesembranol.