Pharmacology

1. ANTIPSYCHOTIC DRUGS
ROLL NO; 40,41

2. OBJECTIVES
 Classification
Mechanism of action
Pharmacological action
Pharmacokinetics
Uses
Adverse effects

3. CLASSIFICATION

4. MECHANISM OF ACTION

5. PHARMACOLOGICAL ACTION
Chlorpromazine
CNS:
Reduce irritational behaviour,aggressiveness
and agitation.
Reduce psychotic symptomatology.
ANS:
Alpha adrenergic blocking activity.
Weak anti-cholinergic action.
LOCAL ANAESTHETIC:
Potent action but has irritant action.

6. CVS:
Produce hypotension due to central and
peripheral action in sympathetic tone.
complication;reflex bradycardia
ENDOCRINE:
Increase prolactin release.
Gynecomastia and galactorrhea can occur.

7. PHARMACOKINETICS:
 Oral and parenteral doses are available.
Oral doses peak at 11/2 hours
intramuscular doses peak at 30 mins
 Highly bound to plasma as well as tissues
protien.
 Metabolites are excreted in bile and urine.
 Divided doses followed by whole doses to
avoid adverse effect

8. CHLORPROMAZINE:
Oral dose:300-1000mg/day
IM:50-100mg/day
TRIFLUPROMAZINE:
ORAL:100-400mg/day
IM:30-60mg/day
THIORIDAZINE:
Oral:300-600mg/day
RISK:Eye damage in long term use

9. TRIFLUOPERAZINE:
15-50mg/day(oral)
1-5mg(IM)
FLUPHENAZINE:
2-20mg/day(oral)
More extra pyramidal side effects and tardive
dyskinesia

10. BUTYROPHENONES:
Haloperidol:
High potency and most widely typical
antipsychotic drug
Features:
Very high incidence of extrapyramidal
adverse effects and tardive dyskinesia
Does not cause weight gain
Preffered drug for acute
schizophrenia,Huntingtons disease , Tourette’s
syndrome
5-30 mg/day oral,5-10 mg(IM)

11. Trifluperidol:
0.5-8.0mg/day oral
2.5-5.0mg(IM)
THIOXANTHINE:
Flupenthixol:
Infrequently used now
Indicated in Schizophrenia and aphathetic
patient
3-18 mg/day (oral)

12. Other Heterocyclic compounds:
Pimozide:
Selective DA antagonist with little alpha
adrenergic or cholinergic blocking activity
Used in Tourett’s syndrome
4-20 mg/day (oral)
Loxapine:
25-250 mg/day (oral)

13. USES:
ORGANIC PSYCHIATRIC DISORDERS
Haloperidol: Delerium ,Dementia , Delerium
tremors
NON ORGANIC PSYCHOTIC DISORDERS:
 Schizophrenia
 Acute psychoses
 Mania
 Bipolar disorders
 Delusional disorders

14. MEDICAL DISORDERS:
 Haloperidol: Huntington’s chorea, Gilles de
la Tourette syndrome
 Chlorpromazine: Intractable hiccups
NEUROTIC AND OTHER PSYCHIATRIC DISORDER:
 Severe anxiety disorder
 Refractory obscessive compulsive disorder
 Anorexia nervosa

15. ADVERSE EFFECTS :
 CNS: Drowsiness , Lethargy
 CVS: Postural hypotension , Palpitation
 Anticholinergic : Dry mouth , Blurred vision
 Metabolic Disturbance: Blood sugar
elevation
 Extrapyramidal effect: Acute dystonia,
Parkinsonism , Akathesia , Neuroleptic
malignant syndrome ,Tardive dyskinesia
 Weight gain