Hello from JustAnswer.
I am sorry that you are having to deal with pancreatic cancer.
There are two primary reasons why hydrocodone/APAP is not working at controlling pain associated with pancreatic cancer. The most common reason is that the pain is of such severity that a stronger opiate is needed. The hydrocodone is one of the lower potency opiates, which is why it is also one of the controlled substances in the lower schedules. In this situation, the usual approach would be to use a stronger opiate, such as oxycodone or morphine. It is also frequently better to use one of these stronger opiates in a sustained release formulation, so that there is a steady level, rather than peaks and valleys.
The other primary reason is that certain pain can occur that even strong opiates are not good at controlling, with the moast common being pain from pressure on a nerve or the cancer growing into a nerve. In these situations, it is usually better to use a medicine that eases the firing of the nerve, and the most commonly used are gabapentin or pregabalin.
In some patients, both approaches are used - both a stronger opiate and a medicine to ease the firing of the nerve carrying the pain message.
Most of these products are available as liquid formulations, although the sustained release formulations of opiates are not. However, there are skin patches that are sustained release preparations of stronger opiates, such as Duragesic patches.
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