GR-89696 is a drug which acts as a highly selective κ-opioidagonist. It shows selective effects in different animal models and it is thought it may be a subtype-selective agonist for the κ2 subtype. Recent studies have suggested that GR-89696 and related κ2-selective agonists may be useful for preventing the itching which is a common side effect of conventional opioidanalgesic drugs, without the additional side effects of non-selective kappa agonists.
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