Most common mechanism of action
Most drugs bind to a macromolecular target structure called a drug target. These are usually proteins such as receptors, transporters, channels, and enzymes, or nucleic acids. For example, opioids interact with endogenous opioid receptors to relieve pain. Targets can also be exogenous structures. Penicillins inhibit bacterial enzymes responsible for building the cell wall of bacteria. And conversely, macromolecules such as false receptors that bind small molecules can be administered as active agents.
More examples
Numerous other mechanisms exist:
- Substitution therapy involves replacing substances, compounds, or cells that the body lacks. For example, vitamins, trace elements, minerals, enzymes, hormones, bacteria (with probiotics), fluid, and blood and its components.
- In an acid-base reaction, neutralization takes place. The antacids taken when the stomach burns are typical representatives with this mechanism.
- Some laxatives osmotically draw fluid into the intestine, making the stool more slippery and promoting bowel emptying.
- Activated charcoal adsorbs toxins to itself and is therefore used as an antidote.
- Chelating agents such as deferoxamine form complexes with ions and lead them to excretion.
- Monoclonal antibodies bind selectively to endogenous or -exogenous structures and cause activation or inactivation. They can also mediate destruction of unwanted cells.
- Destruction of cells and tissues, for example, by means of acids for the external therapy of warts.
- Incorporation of an incorrect substrate in DNA or RNA synthesis (antimetabolites).
- Decay of the active substance under the formation of radioactive radiation.
- In gene therapy, the genetic code of somatic cells of a patient is changed. This can be used to treat hereditary diseases. It can also be intervened at the level of transcription, splicing and translation. In the process, the genes themselves are not changed.
- In cell therapy, the body’s own or foreign cells are multiplied (expanded) and administered locally or systemically. The cells can be modified by genetic engineering. Stem cells are also used.
- Oncolytic viruses are genetically modified and attenuated viruses that selectively attack and destroy cancer cells in the body.
