How does oral medication travel from the stomach to the problem area?


For example, when I take antidepressant pills, how does the active ingredient get from my stomach all the way up to the synapses in my brain?

In: Biology

Your digestive system absorbs the chemical directly into the blood stream. However these chemicals are designed to attach to only certain receptors, so your antidepressant attaches to certain seretonin receptors and blocks them from absorbing the naturally created seretonin. This increases the amount of seretonin in your brain and let’s you have a higher baseline level. This is why they are called Selective Seretonin Reuptake Inhibitors or SSRIs

Chemicals you eat diffuse every where in the body. This is why side effects may exist, because there’s the spot where we want the drugs to go, but they may also cause something somewhere else in the body as well (since the drug goes everywhere).

This is why chemotherapy sucks. Ideally the drug would only go to the tumor, but instead it goes everywhere and wrecks the rest of bodily functions as well, and causes the hairloss. However, there are some cool newer drug designs meant to ‘target’ the tumor instead of being active everywhere, resulting in less chemotherapy side effects.

Different capsules also breakdown at different rates so unload their medication at different areas of your digestive track which is why some are quicker acting than others

When you see the phrase “Targets the source of the pain” or “goes straight to the site of the pain” on pain meds, it’s misleading because it doesnt “target” anything. Like many have already said here, once the meds enter the bloodstream, the active ingredient will go everywhere but only attach to the correct receptors (think the right key for the right lock). So, they can’t “target” anything but will attach (or block) to every available receptor it encounters. Its also worth mentioning that the chemical in the meds often isn’t the cause of the desired effect, it acts as a trigger in a chain reaction resulting in the desired action. This is often through a chain of several protein receptors known as “secondary “messengers” where the triggered receptor will interact with another receptor that could intern interact with another protein receptor (in a message relay) or trigger the release of another chemical or protein that will again illicit some sort of response.