Propoxyphene formulations

Propoxyphene (Schedule II) is another opiate prescribed for pain which is much weaker than those mentioned above. Notice the structural similarities to methadone. Its effects last longer than many other drugs in this class which means it can be taken less frequently and the potential of abuse will be lessened. It can also be formulated with aspirin or acetaminophen in order to have a summation effect. 

SCHEDULE II Certain barbiturates, cocaine, codeine, codeine + acetaminophen (depends on dose and formulation), fentanyl (depends on dose), hydrocodone, hydromorphone, meperidine, methadone, morphine (depends on combination with other pain relievers), oxycodone, propoxyphene... 

As described previously, unpleasant tasting drugs for administration as oral liquids are often presented as suspensions of insoluble salts to improve patient acceptability. An example of this is the bitter tasting analgesic drug, propoxyphene, which is presented as the hydrochloride salt in tablets and as the napsylate salt in oral suspension formulations. 

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