Question
Hello
You have pain in your body. Let's say your shoulder. You take a pain pill. The pain eventually goes away. How do pain pills do this? I know they are probably blocking the pain, but how does the chemicals in the pills go through your body and find that specific part that is in pain?

Thanks for the time.

Answer
David,

I'm not sure which type of pain pill you're asking about so I'll mention a bit about Tylenol, advil, etc (the NSAIDS) and then mention a bit about narcotics and how they work.

When you swallow an NSAID, it does not get digested in your stomach and proceeds directly into your blood system. Once in your blood system, it begins to work, blocking prostaglandins and causing areas of pain to swell. Once those areas swell, the nerve impulses that reach the brain decrease (causing less pain)for as long as the NSAID works.

When it comes to narcotics, they do not help solve the problem of pain. I'm not sure how specific you want me to get, but they do block the pain cycle by binding to proteins that enter the brain. They do not block the pain signal, just the way that the brain interprets the pain. When they cross the blood-brain barrier into the brain. They bind to receptors (different drugs will bind to different receptors- usually endorphins (your body's normal pain relief)). It is the neurotransmitters in your brain that help direct the drug to the receptors. Drugs then interact and change the way which the neurotransmitters interact with the protein receptors.

Inside the central nervous system is also a series of specialized receptors. They are also located within other body systems. These receptors are what bind to drugs and alcohol. Drugs are absorbed into the body moving from area of greatest concentration to lowest concentration.

To eliminate drugs, they must be filtered through the liver more than once to clear your system of the drug.

I hope that helps give you a general explanation about how chemicals find pain in your body. If you are looking for something more specific, I can help but you might also look at a pharmaceutical book that explains how the drug(s) you are looking for work and the name of the receptors. In some cases I'm not sure the entire process or all the mechanisms are completely known but yes for example in  the above cases this is how drugs work in general.

Of course to complicate things, some drugs work on certain people better than others. It is an individualistic response.

I Hope you have a great remainder of your weekend and if you have further questions, don't hesitate to clarify again.

Sincerely,

Jess