/sci/ - Science & Math

>>15160932
>Or is my mistake, as you mentioned, thinking that all medication works by irreversibly binding to enzymes/receptors and in- or activating them? Is there medication that just flows around, occasionally doing its thing until it gets, for example, eliminated by the kidney?
Yes that's it, lots of medications work that way, they don't permanently bond, they interact in a statistical likelihood depending on their concentration, so it's in a balance like any chemical reaction. So you have a set amount of receptors that you want to target with a drug, you give a certain amount of the drug to built up a concentration of the drug in various compartments of the body that are in a chemical balance wih each other. Say one of these compartments is your intercellular space, another one is your blood and another compartment would be the molecule being bound to the receptors that you want to target. The concentration of the drug molecules in these compartments is in a constant balance. Your blood gets filtered by the kidneys, so the blood concentration of the molecules constantly decreases, which leads to molecules from the other compartments shifting into the blood and decreasing the amount of molecules that are bound to and interacting with the targeted receptor, so the effect of the drug starts wearing off. Even drugs that get used up work in that way, with the difference that the molecules that bind permanently to their target can't shift back into the other compartments, but the normal dosage you'll administer includes the anticipation that some of the drug will get filtered out before it can permanently bind to it's target. This is the general simplified gist of it