I’m a doctor. Medications act on enzymes or receptors. These medications can activate receptors, de-activate them or turn on/off chemical pathways.
The question becomes which pathways, when activated/inactivated cause I disruption of homeostasis (the bodies ability to regulate itself). If a drug turns on/off a receptor and the body senses that as a disruption of homeostasis, then the cell will make more receptors so there is more activation or stop
production of those receptors. These are the medications that cause tolerance.
Some medications don’t affect a pathway where upregulation or down regulation by receptor expression is possible, these are the drugs that do not cause tolerance.
Lingering_Louse t1_j79r2b6 wrote
Reply to why you DON'T develop resistance to some medications? by sadra-the-legend
I’m a doctor. Medications act on enzymes or receptors. These medications can activate receptors, de-activate them or turn on/off chemical pathways.
The question becomes which pathways, when activated/inactivated cause I disruption of homeostasis (the bodies ability to regulate itself). If a drug turns on/off a receptor and the body senses that as a disruption of homeostasis, then the cell will make more receptors so there is more activation or stop production of those receptors. These are the medications that cause tolerance.
Some medications don’t affect a pathway where upregulation or down regulation by receptor expression is possible, these are the drugs that do not cause tolerance.