Medics were, unsurprisingly, often put to work in POW camps as camp medics. Usually, POWs were separated by nationality within the camp, and each nationality group would have their own medics, in addition to the German medical personnel within the camp. They were provided with medical supplies by the Germans, although the quality and quantity of those supplies depended on local logistics and dwindled across the board by the end of the war. The quality of medical care provided to Allied prisoners was generally decent and international observers generally regarded it as being within the requirements of the Geneva Convention.

I assume by "Allied" you're referring to the Western Allies rather than Soviets. As you probably know, Soviet POWs were treated far worse than every other prisoner group in German POW camps and were denied even the most basic food and medical care; their medics were allowed to serve as the camp doctors as well, but they were generally given few or no supplies and were often unable to provide any care to their patients. This led to mass death due to epidemics of diseases like typhus and dysentery, particularly in the winter of 1941-1942 when the death rate for Soviet POWs was about 1% per day.

Sorry if that deviated a bit from what you really wanted but I wanted to make sure I gave a substantial answer and gave adequate context for the experience of Western Allied POWs vs. Soviet POWs. If I didn't cover something I can obviously answer follow ups, I spent most of the last five years researching this subject.