An Overview of Antipsychotic Drugs

Introduction to An Overview of Antipsychotic Drugs
Definition of psychosis, Causes of psychosis, Symptoms of psychosis, Classification of anti psychotic drugs, Mechanism of action, Pharmacokinetics, Adverse effects, Therapeutic uses, Contraindications, New inventions
Presented by
T. Niranjan Reddy
Department of Pharmacology

1. AN OVERVIEW OF ANTIPSYCHOTIC DRUGS   A Seminar as a part of curricular requirement for M . Pharmacy I year I Semester Presented by T.Niranjan Reddy (20L81S0109) Department of Pharmacology Under the guidance of Mr . A .Sudheer Kumar M.Pharm . Associate Professor

2. Contents : Introduction Definition of psychosis Causes of psychosis Symptoms of psychosis Classification of anti psychotic drugs Mechanism of action Pharmacokinetics Adverse effects Therapeutic uses Contraindications New inventions References 2

3. Introduction: The psychosis usually involves severe symptoms such as delusions and paranoia. The common belief that anyone who goes crazy or aggressive must be psychotic is not strictly correct in medical terminology. Psychotic disorders focus mainly on the symptoms where the person is detached from reality About 12-23 percentage of people experience psychotic symptoms at some point in their lives. 3

4. DEFINITION Psychosis refers to an abnormal condition of the mind described as involving a “loss of contact with reality” The word Psychosis derived from the Greek i.e ,“ psyche” means mind/ soul and osis - abnormal condition. People experiencing psychosis may exhibit some personality changes and thought disorder. Depending on its severity, this may be accompanied by unusual or bizarre behaviour, as well as difficulty with social interaction and impairment in carrying out daily life activities.

5. The causes of psychosis can be different for everyone, and the exact cause is not always clear . Psychosis could be triggered by the number of factors, such as; Genetics Trauma Psychiatric disorder Medical conditions Psychoactive drugs (alcohol etc ) Medication Causes of psychosis:

6. 6 Signs and symptoms of psychosis INTIAL SYMPTOMS Feeling of suspicion General anxiety Depression Obsessive thinking Distorted perceptions Obsessive thinking

7. 7 Hallucinations Delusions Disorganization in thought, speech or behaviour Disordered thinking Catatonia Difficulty in concentrating Main symptoms:

8. 8 Schizophrenia Bipolar disorder Psychotic depression Schizoaffective disorder Substance induced psychosis Schizophreniform disorder paraphrenia Types of psychotic disorders :

9. 9 Schizophrenia: It is one of the most common type of psychotic disorder The main symptoms are hallucinations (you hear voices or see things that are not real) and delusions (strong beliefs in things hat are not true). Schizoaffective disorder: It is a condition where you can experience both schizophrenia and a mood disorder (depression and bipolar disorder). Bipolar disorder: It is a type of mood disorder that is often characterised by cyclic changes between extreme highs (mania) and low (depression).

10. Substance induced psychotic disorder: When you start or stop certain drugs, you may get substance induced Psychotic disorder. The symptoms include hallucinations and delusions. Drugs which an cause these type of disorder are alcohol amphetamines cocaine LSD opioids Paraphrenia: It is similar to schizophrenia that can be seen in the elderly patients with the age group of 40 It is characterized by paranoid delusions and hallucinations. 10

11. 11 Anti psychotic drugs are also known as neuroleptics or major tranquilizers are a class of medications primarily used to manage psychosis principally in schizophrenia and bipolar disorder First generation antipsychotics known as typical antipsychotics were discovered in the 1950s Second generation drugs known as atypical antipsychotics were discovered in 1960s and introduced clinically in the 1970s. Anti psychotic drugs:

12. 12 Pharamacological classification first generation antipsychotic (low potency) Chlorpromazine Prochlorperazine Thioridazine First generation antipsychotic (high potency) Fluphenazine thiothixene Haloperidol Pimozide Second generation antipsychotics Aripiprazole olanzapine Asenapine quetiapine Clozapine risperidone Lurasidone ziprasidone Classification of anti psychotic drugs:

13. 13 Mechanism of action:

14. 14

15. 15 Oral absorption of chlorpromazine is somewhat unpredictable and bioavailability is low It is highly bound to plasma as well as tissue proteins Volume of distribution therefore is large (20L\KG) It is metabolized in liver mainly by CYP 2D6 into a number of metabolites The acute effects of a single dose of chlorpromazine generally last for 6-8 hours The t1\2 ( elimination )half life is usually 18-30 hours The metabolites are excreted in urine and bile. Pharmacokinetics

16. Adverse effects Drowsiness, lethargy, mental confusion with low potency typical antipsychotics and some atypical ones like quetiapine and clozapine Increased appetite and and aggravation of seizures in epileptics Weight gain Orthostatic hypotension, palpitation, Q-T interval prolongation and cardiac arrythmiasis Dry mouth and blurred vision Constipation and urinary retention Extrapyramidal symptoms such as pseudo parkinsonism , akinesia (muscular weakness), akathisia (continuous restlessness and fidgeting) and dystonia (involuntary movements of face, legs , arms and neck). 16

17. Therapeutic uses: Used to treat schizophrenia Used in the prevention of severe nausea and vomiting Used to treat depression and mania Chlorpromazine is used to treat intractable hiccups Risperidone and haloperidol are also commonly prescribed for this tic disorder Used to treat alcoholic hallucinations. 17

18. contraindications: These drugs are contraindicated in Hypotension CNS depression Pregnant women Liver, renal or cardiac insufficiency. NEW INVENTIONS: Paliperidone Asenapine Lurasidone 18

19. References : TRIPATHI , K.D. “Essentials of Medical Pharmacology Textbook of pharmacology 7 th edition 2013 p.463. eucht , S. et al. Second-generation versus first-generation antipsychotic drugs for schizophrenia: a meta-analysis.  Lancet   373 , 31–41 (2009).  Emsley R, Rabinowitz J, Medori R. Time course for antipsychotic treatment response in first episode schizophrenia.  Am J Psychiatry  2006 19

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