Note the following:

8.1 Propoxyphene (Darvon)

If used regularly to control cancer pain will likely cause frequent unpleasant side-effects (confusion, nausea) and usually poor pain control.

8.2 Pethidine/ Meperidine (Demerol)

This is a poor choice in treatment of chronic cancer pain because it is poorly absorbed by mouth, has a shorter duration of action than most other narcotics, and when used regularly over weeks causes myoclonus and sometimes convulsions because of accumulation of normeperidine which is toxic to the central nervous system.

8.3 Pentazocine (Talwin)

Another poor choice in treatment of chronic pain of cancer because of poor oral absorption and prominent central nervous system excitatory side-effects, such as hallucinations and confusion.

Note: This drug is a partial antagonist of morphine, hence should never be combined with morphine or its congeners (e.g. hydromorphone, fentanyl).

8.3.1 Brompton's Cocktail

Formerly used to control cancer pain but no longer advised because of frequent unpleasant side-effects due to presence of chloroform, cocaine and sometimes alcohol; much better pain control with fewer side-effects is achieved by using one narcotic and perhaps one co-analgesic.

Note: Some hospital pharmacies call their morphine solution "Brompton's," presumably to disguise the word "morphine," so be sure you know what you are prescribing.