Morphine therapeutic applications

Thebaine was isolated from opium in 1835 by Pelletier (439). The therapeutic applicability of thebaine was studied by Balint et al. (440). It was found to be more toxic than morphine. It is a more effective narcotic but a weaker analgesic than morphine. The analgesic effect of thebaine in doses of 0.01 g/kg is greater than that of amidopyrine this effect persists, however, only over a period of 30 min. Dihydro-thebaine is somewhat more effective but it is more toxic (441). The number and the location of the double bonds in ring D of the morphinane skeleton is of importance for the analgesic effect. Teraoko... 

Finally, the ability of aprepitant to block emesis, a therapeutically relevant endpoint for the ultimate clinical application of the drug, as discussed below, was tested in the presence of several emetogens in the ferret. This species is believed to be a valid animal model for cancer chemotherapy-induced emesis in humans. Aprepitant (1) effectively blocked retching and vomiting due to cisplatin, apomorphine, and morphine at a dose of 3.0 mg/kg p.o. and 0.3 mg/kg i.v. (in the case of cisplatin).8... 

One of the earliest applications of organic chemistry to therapeutics was the synthesis of compounds that have narcotic (sleep-inducing) and anesthetic properties free of the dangers of morphine-containing preparations that had been in use for these purposes prior to modem chemistry. 

Morphine is also stiU in use today for extreme pain, as in cases of severe burns or open fractures, where its application is limited to emergencies, because of the significant risk of addiction. Conversely (+)-morphine, like (+)-codeine or (+)-heroin, possesses no analgesic effect. By comparison with (-)-morphine, (-)-codeine is much less effective however, it inhibits selectively the cough centre, and has a substantially lower potential for addiction. It is therefore the main component of many cough syrups. Thebaine, on the other hand, produces like strychnine severe convulsions, and finds therefore no therapeutic applica-... 

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