Antipsychotic drugs by Dr. Nagaveni Gorla

1. Dr. Nagaveni
ASST.PROF
PHARMACOLOGY

2. Psychiatric conditions are divided into-
 Psychosis,
 Neurosis
 Affective disorders.

3.  PSYCHOSES:
 Loss of ability to recognize reality
 Severe distortion of thinking process
 Delusions and hallucinations
E.g. Schizophrenia
 It could be due to:
 An organic cause
 Functional cause .

4. NEUROSIS:
 Anxiety
 Phobias
 Obsessive compulsive disorders
 hysteria
 reactive depression

5. Affective disorders ( mood disorders):
 Endogenous depression
 Mania
Bipolar
unipolar

6. Limbic system
Mania
Depression
Schizophrenia
Increased NA activity
Depletion of NA or 5-HT
Increased DA activity

7. What are psychotropic drugs:
The drugs that affects the mental function
are called psychotropic agents.

8.  Neuroleptic or antipsychotic drugs or
antischizophrenic drugs
 Anxiolytic drugs
 Antidepressants
 Antimanic drugs

9.  TRANQUILLIZER is a drug that brings about
tranquility by calming, soothing and quietening
effects.
 major: neuroleptics and barbiturates
 minor: Benzodiazepines

10.  Also called anti-schizophrenic or major
tranquilizers.
 Definition:
The drugs which are effective in the
treatment of schizophrenia and other
agitated states.

11.  It is a type of functional psychoses in
which severe personality changes and
thought disorders.

12. POSITIVE SYMPTOMS NEGATIVE SYMPTOMS
 Delusions
 Auditory
hallucinations
 Distortion of thought
 Abnormal behavior
 Flattening of
emotional response
 Poverty of speech
 Inability to get
pleasure from any
activity
 Lack of energy to
work
 Failure to pay
attention

13. 1. Genetic predisposition.
2. Abnormalities in amine neurotransmitter function.
 Dopamine (DA) Hypothesis:
Excessive dopaminergic activity
 5-HT Hypothesis:

15.  TYPICAL
ANTIPSYCHOTICS:
 Phenothiazines:
Chlorpromazine,
Thioridazine,
Trifluperazine
 Thioxanthines:
Flupenthixol, Thiothixine,
 Butyrophenones:
Haloperidol, Droperidol
ATYPICAL OR NOVEL
ANTIPSYCHOTICS
Clozapine
Olanzapine
Quetiapine
Risperidone,
Ziprasidone
Aripiprazole

16.  Competitive blockade of post synaptic D2 receptors
 Blockade of D4 and 5-HT2A receptors by atypical anti
psychotic drugs

17. 
 Blockade of D2 in mesolimbic system - Antipsychotic
effect
 Blockade of D 2 in NST – extra pyramidal effects.
 Blockade of D2 in CTZ – antiemetic.
 Blockade of D2 in ant.pituitary – hyperprolactinemia
 Blockade of D2 in cortex – Sedation
 Blockade of D2 in hypothalamus – Hypothermia

18.  Other actions:
AUTONOMIC NERVOUS SYSTEM:
 Blocks alpha receptors
Orthostatic hypotension & tachycardia
 cholinergic receptor blockade:
dry mouth, blurred vision, tachycardia, urinary retention
HISTAMINE RECEPTOR BLOCKADE:
Sedation
LOCAL ANESTHETIC ACTION

19.  Due to extension of pharmacological actions
 Hypersensitivity reactions

20.  Due to extension of pharmacological actions
CNS:
 Sedation, drowsiness, mental confusion, convulsions
 Increased appetite and weight gain

21. ANS:
 Antiadrenergic:
postural hypotension, tachycardia, inhibition of ejaculation
Anticholinergic:
Dry mouth, blurred vision, urinary retention, constipation,
ENDOCRINE:
Hyperprolactinemia, gynaecomastia, galactorrhoea in
males
Amenorrhea and infertility in females

22. Extrapyramidal side effects:
 Acute dystonias
 Akathisia
 Parkinsonism
 Nueroleptic malignant syndrome
 Tardive dyskinesia
 Perioral tremors

23. Dystonias:
Charecterized by spasm of muscles of tongue, face neck and
back.
Treated by anti histaminic –Anti Cholinergic drug – Promethazine.
2. Akathisia:
Characterized by uncontrollable motor restlesness.
Treated by a non –selective beta blocker-propronolol.
3. Parkinsonism:
Due to disturbance in the balance between DA-Ach balance
in the basal ganglia due to D2 receptor blockade.
Rx-centrally acting anti cholinergics –
Benzhexol,Procyclidine,Benztropine.

24. . Neuroleptic - malignant syndrome (NMS):
Characterized by Hyperthermia, muscular rigidity, autonomic
dysfunction with tachycardia, sweating, urinary incontinence
and labile BP.
 Management:
 Discontinuation of neuroleptic
 Supportive therapy for fever and muscular rigidity.
 Peripherally acting muscle relaxant – Dantrolene.

25. Perioral tremors(Rabbit syndrome) :
occurs after long term Rx with potent classical
neuroleptic.
Characterized by rapid chewing movements.
Rx -Anti cholinergic- Anti parkinsonian drugs.
Tardive dyskinesia:
Characterized by repetitive involuntary movements of
eyelids and face
Supersensitivity of DA rec caudate

26. B. DUE TO HYPERSENSITIVITY REACTIONS
 Agrnulocytosis
 Cholestatic jaundice.
 Photosensitivity
 Contact dermatitis

27. 1) With CNS depressants
2) Levodopa
3) Metoclopramide
4) The drugs producing anticholinergic side effects
( Antidepressants and antihistamines )
5) With morphine

28.  Schizophrenia
 Manic depressive psychosis
 Behavioral disorders in children
 Vomiting
 Hiccups
 Drug dependence
 Pre-anesthetic medication.
 To induce hypothermia in cardiac surgery
 Tourette’s syndrome

29. ADVANTAGES:
 Relieve the negative symptoms
 Effective for Resistant cases
 less extra pyramidal side effects
 Less ANS side effects
 Less hyperprolactinemia
 Suitable for levodopa induce psychosis

30. DISADVANTAGES:
 More weight gain
 Seizures with clozapine
 Agranulocytosis with clozapine
 Hyperlipidemia and hyperglycemia with clozapine
and olanzapine

31.  Antipsychotic
 Anti-manic
Anti-anxiety
 Anti-emetic
 Anti-GH,
 Anti-arrhythmic
 Anti-hiccough
 Anti fertility
 Anti-dopaminergic
 Anti-serotinergic
 Anti-cholinergic
 Anti-histaminic
 Anti-adrenergic
 Anti-allergic
 Anti-shock, anti-
tetany,
 LA, increase PL