Bremazocine is a κ-opioid receptor agonist related to pentazocine. It has potent and long-lasting analgesic and diuretic effects. Bremazocine is a kappa-opioid receptor agonist with potent analgesic and diuretic activities. As an analgesic it is three- to four-times more potent than morphine, as determined in both hot plate and tail flick tests. Bremazocine and other benzomorphan analogs were synthesized in an effort to produce opiates with greater kappa-opioid receptor selectivity and with minimal morphine-like side effects. Unlike morphine bremazocine is devoid of physical and psychological dependence liability in animal models and produces little or no respiratory depression. While bremazocine does not produce the characteristic euphoria associated with morphine and its abuse, it has been shown to induce dysphoria, a property that limits its clinical usefulness.