Papaverine

Papaverine (Latinpapaver, "poppy") is an opiumalkaloidantispasmodic drug, used primarily in the treatment of visceral spasms and vasospasms (especially those involving the intestines, heart, or brain), occasionally in the treatment of erectile dysfunction and acute mesenteric ischemia. While it is found in the opium poppy, papaverine differs in both structure and pharmacological action from the analgesic morphine and its derivatives (such as codeine).

One study has suggested that excessive consumption of uncooked katuk leaves can cause lung damage due to the high concentrations of papaverine present.