Recreational drugs
Recreational drugs can affect neurotransmitters in the reward pathway within the brain. They can act as either agonists or antagonists. Recreational drugs can also stimulate the release of neurotransmitters or inhibit their reuptake.
By affecting the neurotransmission at synapses, recreational drugs can cause changes in mood, awareness, perception and behaviour.
Agonists
Repeated use of drugs which act as agonists leads to drug tolerance.
Agonists stimulate specific receptors which decreases the number and sensitivity of the receptors. As the sensitivity has decreased, as individual must take more of the drug to trigger the receptors and therefore feel the effects.
Antagonists
Repeated use of drugs which act as antagonists can lead to drug addiction.
Antagonists block specific receptors which increases both the number and sensitivity of these receptors. As a result of this sensitisation leads to the individual craving more of the drug.