Eight healthy participants were included in this placebo-controlled study examining the physiological and subjective effects of salvinorin A (SA). Participants were administered ascending sublingual doses of salvinorin A (0–4,000 μg) over 7 sessions with a washout period of at least 24 hours between sessions, with the first two doses (placebo and 100 μg) being administered in a double-blind manner and the remaining 5 doses (250, 500, 1,000, 2,000, and 4,000 μg) administered in a single-blind manner. Physiological effects were measured using heart rate, blood pressure and oxygen saturation. Blood plasma and urine concentrations of SA and salvinorin B (SB) were analysed using a liquid-chromatographic-atmospheric pressure chemical ionization-tandem mass spectrometric (LC-APCI-MS/MS) method. Subjective drug effects were assessed using two participant-rated VAS questionnaires, as well as the Subjective Drug Effects Questionnaire (SDEQ), Altered States of Consciousness Questionnaire (APZ-OAV), and Positive and Negative Affect Schedule (PANAS). No significantly physiological or subjective effects were observed for any SA dose compared to placebo. SA was detectable in plasma and urine, however it was often below the reliable limit of quantification.