Partial agonist at 5HT1A and D2, and 5HT2A antagonist
F.
Pure opioid antagonist (will reverse mu, delta, and kappa)
G.
Partial agonist at the mu-opioid receptor
H.
NMDA agonist
I.
Alpha 2 agonist
J.
Weak MAOI and weak SNRI
Match the following with the correct mechanism of action
NaN.
St John's Wort
Weak MAOI and weak SNRI 87%
NaN.
Varenicline
Nicotinic receptor partial agonist 85%
NaN.
Buprenorphine
Partial agonist at the mu-opioid receptor 79%
Mechanism of action
It is important to know the mechanisms of action of the different drugs. These are common questions in the exam, and easy marks if you make an effort to learn them.
Antidepressant
Mechanism
Mirtazapine
Noradrenaline and serotonin specific antidepressant (NaSSa) 5HT2 antagonist, 5HT3 antagonist, H1 antagonist, alpha 1 and alpha 2 antagonist, moderate muscarinic antagonist
Venlafaxine
Serotonin and noradrenaline reuptake inhibitor (SNRI)
Duloxetine
Serotonin and noradrenaline reuptake inhibitor (SNRI)
Reboxetine
Noradrenaline reuptake inhibitor (NaRI)
St John's Wort
Weak MAOI and weak SNRI (also considered by some to be a weak SSRI)
Trazodone
Weak antagonist and SARI (Serotonin antagonist and reuptake inhibitor)
Moclobemide
Reversible inhibitor of monoamine oxidase type A
Agomelatine
Melatonergic agonist (MT1 and MT2 receptors) and 5-HT2C antagonist
Bupropion (Zyban)
Norepinephrine-dopamine reuptake inhibitor (NDRI), and nicotinic acetylcholine receptor antagonist
Antidementia drug
Mechanism
Donepezil
Reversible acetylcholinesterase inhibitor
Rivastigmine
Reversible acetylcholinesterase inhibitor and butyrylcholinesterase inhibitor
Galantamine
Reversible acetylcholinesterase inhibitor and binds allosterically to the nicotinic acetylcholine receptor
Tacrine
Reversible acetylcholinesterase inhibitor
Memantine
NMDA antagonist
Mood stabiliser
Mechanism
Valproate
GABA agonist and NMDA antagonist
Gabapentin
GABA agonist
Topiramate
GABA agonist, NMDA antagonist, and Na channel stabiliser
Carbamazepine
Stabilises Na channels
Phenytoin
Stabilises Na channels
Lamotrigine
NMDA antagonist and stabilises Na channels
Pregabalin
Potent ligand for the alpha-2-delta subunit of voltage-gated calcium channels in the central nervous system
Anxiolytic/hypnotic drug
Mechanism
Benzodiazepines
GABA-A agonists
Z-drugs
GABA-A agonists
Buspirone
5HT1A partial agonist
Antipsychotic
Mechanism
Amisulpride
D2/D3 selective antagonist (low affinity selective antagonist of 'D2 like' receptors (D2=D3>D4) it has little affinity for D1 like' receptors (D1 and D5) or non dopaminergic receptors (serotonin, histamine, adrenergic, and cholinergic)
Olanzapine
Dopamine and 5HT2 antagonism
Aripiprazole
Partial agonist at 5HT1A and D2, and 5HT2A antagonist
Clozapine
High affinity for D4, (to a lesser extent D1, D2, D3, D5) also 5 HT 1A partial agonist and 5HT2 antagonist
Drug of abuse
Mechanism
Ketamine
NMDA antagonist
Phencyclidine
NMDA antagonist
Other drug
Mechanism
Lofexedine
Alpha 2 agonist
Clonidine
Alpha 2 agonist
Buprenorphine
Partial agonist at the mu-opioid receptor
Naloxone
Pure opioid antagonist (will reverse mu, delta, and kappa)
Atomoxetine
Noradrenaline reuptake inhibitor
Varenicline (Champix)
Nicotinic receptor partial agonist
Disulfiram
Binds irreversibly to aldehyde dehydrogenase
Acamprosate
Metabotropic glutamate receptor antagonist and GABA-A agonist
Selegiline
selective, irreversible inhibition of monoamine oxidase type B (also inhibits MAO-A at higher doses
Sildenafil
Inhibits cGMP-specific phosphodiesterase type 5 (PDE5)
