There is a saying among non-allopathic health care folks that goes, “You can’t heal what you can’t feel.” It’s the argument for not using analgesics unnecessarily: If you don’t really need it, don’t take a pain killer. It impairs your body’s ability to feel itself (by definition, right?) and that will impair your body’s ability to heal itself.

Is this true? Is there any evidence that taking a ibuprofin prolongs the whatever-it-is that’s causing your headache? That taking dextromathorphan makes your cough last longer? I understand that taking drugs can allow you to continue pushing your body, and that that could prolong a sickness. I understand that your liver has to deal with these chemicals, and that’s probably not good for it. But if all other things were equal–the same amount of rest and your liver is just fine, for example–would you get better faster if abstain from drugs than if you take them?