The term “mechanism of action” is a pharmacological term commonly used when discussing medications or drugs.
Mechanism of actionandmode of actionare sometimes used interchangeably, though the latter can be used in more general terms.
Mechanism of action refers to the biochemical process through which a drug produces its effect.
Christopher Furlong/Getty Images News/Getty Images
For example, if you have a bacterial infection, your doctor might say that you need an antibiotic.
They study the cells closely and watch how they interact.
Their observations reveal how the drug attacks and kills the bacteria.
Agonists vs. Antagonists
Drugs that are agonists activate the receptors they bind to.
This bond will either increase or decrease the activity within the cell.
Most drugs bind to a specific punch in of receptor (which is known as receptor selectivity).
The ability of a drug to bind to a certain receptor is determined by its unique chemical structure.
Sometimes the mechanism of action of a drug is knownother times, it’s not fully understood.
For example, the mechanism of action ofselective serotonin reuptake inhibitors (SSRIs)is well known.
Sometimes, a medication’s mechanism of action is unknown.
Some drugs have more than one known mechanism of action.
For example, drinking a cup of coffee might increase your heart rate and also stimulate intestinal contractions.
National Cancer Institute.Mechanism of action.
2010;107(33):14621-14626. doi:10.1073/pnas.1000138107
National Cancer Institute.NCI Dictionary of Cancer Terms: Antagonist.
Berg KA, Clarke WP.Making sense of pharmacology: Inverse agonism and functional selectivity.Int J Neuropsychopharmacol.
