Typical antipsychotic

anti psychotic drugs

1. Prepared by : Hamad Emad D huhayr Typical antipsychotic

2. General concepts Mechanism of action Indications Side effects SPECIFIC ANTIPSYCHOTIC MEDICATIONS Conclusion Contents:-

3. They have an equal or greater affinity for D 2 receptors than for 5-HT 2 receptors Antagonism of D 2 receptors in mesolimbic pathways suppress the positive symptoms of Schezophrenia . Blockade of D 2 receptors in the basal ganglia is responsible for parkinsonian and other extrapyramidal side effects of anti psychotic drugs General concepts for typical

4. The exact mechanism of action of antipsychotic drugs is unknown . According to the dopamine theory of schizophrenia, positive symptoms are the result of an overactivity in the mesolimbic dopamine pathway . first-generation antipsychotics are D2 antagonists . As a result, they reduce dopaminergic neurotransmission in the four dopamine pathways. Mechanism of action

5. Psychomotor Agitation: High potency APMs ( Haloperidol ) are used because injections are available Schizophrenia : Treatment of choice for acute psychotic episodes & for prophylaxis Other Psychotic Disorders: Treatment of Psychoses & Cognitive disorders due to general medical conditions & substances, delusional disorder, brief psychotic disorder , Indications

6. schizophreniform disorder & other rarer psychotic disorders ! Mood Disorders: Treatment of Agitation & Psychosis during mood episodes ! Sedation: Useful when Benzodiazepines are contraindicated (specially in older patients) or as an adjunct during anesthesia ! Movement Disorders: Treatment of choice for Huntington disease & Tourette disorder

7. Side effects

8. TARDIVE DYSKINESIA (TD) Characterized by irreversible Choreoathetosis & other involuntary movements Movements often occur first in the tongue or fingers & later involve the trunk Movements disappear during sleep Etiology may be a form of “chemical denervation hypersensitivity”, which is caused by chronic Dopamine blockade in the basal ganglia Older Patients who take high doses of older APMs for long periods of time are at highest risk & movements gradually worsen with continued use o Treatment ! Stop older APMs ! Use newer APMs

9. ! Chlorpromazine (Older Low-Potency D2) o Highly Sedating. More Hypotension. More Anticholinergic effects o Low frequency of EPS o Few remaining indications for primary selection ! Haloperidol (Older High-Potency D2) Less Sedating. Less Hypotension. Less Anticholinergic effects High frequency of EPS Remain useful for Rx of Acute Agitation , especially via IM injections Long acting ( Haloperidol : once q 4 wks & Fluphenazine : once q 2 wks ) SPECIFIC ANTIPSYCHOTIC MEDICATIONS

10. First-generation antipsychotics are also known as: typical antipsychotics, conventional or classic antipsychotics and dopamine antagonists. FGAs reduce dopaminergic neurotransmission in the four dopamine pathways by blocking D2 receptors. FGAs differ in potency, not effectiveness. High-potency: haloperidol, fluphenazine Mid-potency: perphenazine , loxapine Low-potency: chlorpromazine Conclusion

11. References &