Tonicity clinical significance

Oripavine is an opiate and the major metabolite of thebaine. It is the parent compound from which a series of semisynthetic opioids are derived, which includes the compounds etorphine and buprenorphine. Although its analgesic potency is comparable to morphine, it is not used clinically due to its severe toxicity and low therapeutic index. Oripavine possesses an analgesic potency comparable to morphine however, it is not clinically useful due to severe toxicity and low therapeutic index. In both mice and rats, toxic doses caused tonic-clonic seizures followed by death, similar to thebaine. Oripavine has a potential for dependence which is significantly greater than that of thebaine but slightly less than that of morphine. 

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