Atypical antidepressants Flashcards
What is the effect of activation of alpha 2 receptors of the pre-synaptic neurones by dopamine and 5-HT ?
It inhibit the release of dopamine and 5HT to the synaptic cleft.
What is the indication for atypical depressants in treating MDD?
They are used when the patients do not respond to the conventional first line anti depressants.
What are the commonly used atypical depressants?
Mirtazapine, Trazodone, Nefazodone, Vilazodone, Vortioxetine, Bupropoin.
What is the MOA of Mirtazapine ?
It inhibits alpha 2 receptors, 5HT2a and 3a receptors, and H1 receptors. Its main depressant effect comes from the inhibition of alpha 2 receptors which reduces the inhibition of presynaptic neurones leading to increased norepeinephrine and dopamine release.
What is the effect of mirtazapine on serotonergic transmission and its significance to depression?
Mirtazapine selectively binds to 5HT2a and 3a receptors, but spares 5HT1a which has a stronger anti-depressent effect. While inhibition of 5-HT3a receptors reduces nausea and vomiting. inhibition of H1 leads to sedation.
What are the side effects of Mirtazapine ?
- dry mouth
- Increased appetite
- Weight gain
What is the MOA of Trazadone and Nefazodone ?
They inhibit 5HT2a which leads to more serotonin binds to 5HT1a receptor. In addition, they are also weak inhibitors of SERT which increases the availability of serotonin in the synaptic cleft.
Why are Trazadone and Nefazodone used to treat insomnia ?
Due to strong H1 inhibition.
What is the consequence of alpha o1 inhibition by Trazadone and Nefazodone ?
Orthostatic hypotension and Priapism.
What is the rare side effect of Nefazodone ?
Severe liver damage.
What is the MOA of Vilazodone and Vorteoxitine ?
They are potent inhibitors of SERTs and directly agonise 5-HT1R.
_______is a partial agonist of 5HT1R.
Vilazodone.
_______is a full agonist of 5HT1R
Vortioxitine.
What is the major side effect of Vilazodone and Vorteoxitine ?
Serotonin syndrome
Vortioxitine can cause _______?
abnormal dreams.
