When taken at the recommended dose (≤0.2 mg per kg of body weight), yohimbine may cause nausea, abdominal pain, dizziness, nervousness, and anxiety.[1]
Higher doses of yohimbine may be dangerous; a report from 2005 found that yohimbine had the highest rate of toxic effects of any botanical product.[2] Case reports of excess yohimbine ingestion have suggested that anxiety, hypertension (high blood pressure), tachycardia (high heart rate), arrhythmias, and agitation are among the more severe side effects of this compound.[3]
Furthermore, many yohimbine-containing supplements in the U.S. were found to be inaccurately labeled — they contained 23%–147% of the yohimbine reported on the label and failed to report the amount of yohimbine contained in the product or warn of the potential harms of excess consumption.[4]