Asimadoline

Asimadoline (EMD-61753) is a drug which acts as a peripherally selective κ-opioid receptor (KOR) agonist. Because of its poor ability to cross the blood–brain barrier, asimadoline lacks the psychotomimetic effects of centrally acting KOR agonists, and consequently has more potential for medical use, and has been researched as a possible treatment for irritable bowel syndrome, with reasonable efficacy seen in clinical trials.