Antagonist

How it is used

Many drug classes are antagonists even though their names say 'blocker': beta blockers, H2 blockers. Antagonists can be competitive or non-competitive. Naloxone, an opioid antagonist, reverses the effects of an opioid overdose by pushing opioids off their receptors.

Example sentences

1. Naloxone is an opioid antagonist used in emergencies.

2. Beta blockers act as antagonists at beta-adrenergic receptors.

Common collocations

• receptor antagonist
• competitive antagonist
• opioid antagonist
• act as an antagonist

Related terms

• agonistA drug that binds to a receptor and activates it, producing an effect similar to that of the body's own natural substance.
• receptorA protein on or inside a cell that a drug or a natural substance such as a hormone binds to, starting a change in how the cell works.
• beta blockerA medicine that blocks the effects of adrenaline on beta receptors and slows the heart rate, used for angina, heart failure, irregular heartbeat and high blood pressure.
• opioidA strong painkiller that acts on opioid receptors in the brain and spinal cord, such as morphine, oxycodone, fentanyl, codeine or tramadol.

This word in other fields

The same English word can have a different meaning in another field:

• antagonist · Literature

More terms: Pharmacodynamics and Drug Action

• pharmacology
• pharmacodynamics
• mechanism of action
• therapeutic index
• efficacy
• potency
• tolerance
• onset of action