[PCOL-FIN-01-PT4] ANTIPSYCHOTICS

THIS FLASHCARDS IS ABOUT [PCOL] MOA OF 1ST & 2ND GEN ANTIPSYCHOTICS.

Blocks D₂-receptors

What is the general MOA of 1st Generation Antipsychotics?

Brain

D₂-receptors are most distributed where?

• Histamine

• Alpha

• Muscarinic

Miscellaneous Effect of 1st Gen Antipsychotics:

It blocks what receptors?

Hint: HAM (Anti HAM = Anticholinergic)

Cholinergic

Muscarinic receptors are?

Dose

Potency has something to do with the?

1. D₂-receptors affinity

2. HAM-receptors affinity

The MOA of 1st Gen Antipsychotics:

1. Potency is directly proportional to?

2. Potency is Inversely proportional to?

Info

Directly Proportional: Potency

If the drug (antipsychotic) is more potent, the D₂-receptor blocking activity is enhanced.

Info

Inversely Proportional: Potency

If the drug (antipsychotic) is more potent, the anti-HAM activity is decreased.

Efficacy

This has something to do with the maximal or peak response/effectivity of the drug.

Potency

This is the dose required to achieve 50% of maximal response of the drug.

(Lower dose = higher potency)

Info

• The D₂-receptors blockade activity is enhanced if the drug is potent. Because at lower dose of antipsychotics it targets D₂-receptors.

• At lower dose, D₂-receptors are enhanced.

• If the dose is lower, the antipsychotics will not reach HAM receptors.

Info

Potent drugs requires low dose, because of the low dose, the HAM will not be reached.

Info

butyrophenone = piperazines > piperidines ≥ thioxanthenes > aliphatic

• Butyrophenone and piperazines are equally potent.

• Piperazines are much potent.

• Piperidines is potency is greater than or equal to thioxanthenes

• Aliphatic are least potent in the 1st gen antipsychotics.

Info

1st Generation Antipsychotics is taken to block D₂-receptors and could also have anti-HAM properties but it varies in potency.

Info

2nd Generation Antipsychotics has the same efficacy with the 1st Generation but it has lesser side/adverse effects.

• Clozapine

• Olanzapine

• Loxapine

• Risperidone

• Paliperidone

• Quetiapine

• Ziprasidone

• Aripiprazole

• Molindone

• Amisulpride

What are the (10) Drugs under 2nd Generation/Atypical Antipsychotics?

Hint: COLoRis PaQueZ AMA

• D₂

• D₄

• 5-HT₂

2nd Generation Antipsychotics blocks what receptors (3)?

Info

What would happen if the 5-HT receptors are blocked?

Decrease dopamine in the limbic system.

Schizophrenia

Clinical Applications of 1st/2nd Gen Antipsychotics:

They are effective in treating positive/negative symptoms of?

2nd Gen

This generation of antipsychotics is much more effective in treating negative symptoms of schizophrenia.

• Mania

• Tourette’s syndrome

• Depression

There are few antipsychotics that is also used for?

Hint: Man-Tou-Dep