Yohimbine HCl is the hydrochloride salt of yohimbine, an alkaloid from the bark of the *Pausinystalia yohimbe* tree. Supplement makers use this form because it is standardized and water-soluble. That means absorption and dosing stay more consistent, unlike crude yohimbe bark extracts. The compound blocks alpha-2 adrenergic receptors, which ramps up sympathetic nervous system activity.
People often take it on an empty stomach 30 to 60 minutes before exercise to boost energy and support fat mobilization. Many stack it with caffeine, a combination that also amplifies the chance of side effects.
This is a potent substance with a narrow safety margin. Rapid heart rate, high blood pressure, anxiety, and tremors can occur. It interacts dangerously with stimulants and several classes of antidepressants (SSRIs, SNRIs, MAOIs). Professional guidance is strongly advised before use.