Anti Psychotics Flashcards
1
Q
Classification of anti psychotic?
A
CLASSIFICATION
PIABO
1. Phenothiazines: Chlorpromazine, triflupromazine, trifluoperazine, thioridazine, fluphenazine
2. Thioxanthene: Flupenthixol
3. Butyrophenones: Haloperidol, trifluperidol
4. Atypical antipsychotics: Risperidone, clozapine, olanzapine, quetiapine, zotepine, aripip-
razole, amisulpride, ziprasidone
5. Others: Loxapine, pimozide
2
Q
Adverse effects of anti psychotics ?
A
- Important side effects of these drugs are dose-dependent extra-pyramidal symptoms (EPS).
Parkinsonism: They are tremors, rigidity, hypokinesia, etc. Centrally acting anticholiner-gics (benzhexol, benztropine and antihistamines like promethazine, diphenhydramine, etc.) are effective in controlling these symptoms.
• Acute dystonias: Sudden onset of muscle spasms resulting in uncontrolled muscular movements involving the face, tongue, neck, etc. It responds to centrally acting anticholinergics (eg. ben-zhexol) or antihistaminics with anticholinergic action, e.g. promethazine and diphenhydramine.
• Akathisia: Feeling of restlessness - the person cannot sit at a place and has a desire to move about. It is treated with a BZD (eg. clonazepam) or B-blocker (eg. propranolol) or centrally acting anticholinergic.
• Neuroleptic malignant syndrome: It is a rare but serious complication, characterized by muscular rigidity, hyperpyrexia, mental confusion and coma. It is treated with i.v. dantrolene.
• Tardive dyskinesia (Tardive - late occurring): It is characterized by involuntary movements of the mouth) tongue and the upper limbs. It develops in approximately 20% of patients after months or years of antipsychotic treatment. Treatment is usually unsuccessful. - Muscarinic, a-adrenergic and H,-receptor-blocking side effects (Fig. 7.14).
- Weight gain is common with clozapine and olanzapine.
/ Endocrine side effects are due to increased prolactin level resulting in amenorthoea, galac-torthoea and inferfility in females; gynaecomastia in males. Hyperglycaemia and precipitation of diabetes can occur with chlorpromazine.
Hypersensitivity reactions can occur - skin rashes, itching, dermatitis, leukopaenia and rarely obstructive jaundice. Agranulocytosis is a serious adverse effect with clozapine.
3
Q
Therapeutic uses of anti psychotics
A
- Schizophrenia: The neuroleptics are the only efficacious drugs available for the treatment of schizophrenia (for effects in schizophrenia (see p. 226). The atypical antipsychotics are commonly prescribed owing to the lower risk of EPS. They suppress both positive symptoms (hallucinations, delusions, etc) and negative symptoms (social withdrawal, lack of motivation, inability to feel pleasure). Risperidone, olanzapine, aripiprazole, ziprasidone and quetiapine are frequently used. Clozapine is reserved for resistant cases of schizophrenia because of risk of agranulocytosis. Of the older agents, haloperidol and fluphen-azine are commonly used. For acute schizophrenia, haloperidol is used. Older agents are less effective than atypical antipsychotics against negative symptoms of schizophrenia.
- Mania and bipolar disorder: For treatment of acute mania, i.m. haloperidol/olanzapine is effective. For oral administration, olanzapine, quetiapine, risperidone and aripiprazole can be used. Atypical antipsychotics can be combined with lithium for maintenance therapy of bipolar disorder.
- As antiemetic: These drugs (phenothiazines, haloperidol, etc.) produce antiemetic effect by blocking Dz-receptors in CTZ. However, they are not routinely used as antiemetics because of their side effects. Phenothiazine, such as prochlorperazine, is useful for prevention and treatment of nausea and vomiting associated with migraine or emesis due to anticancer
drugs.
%. Intractable hiccough has been treated with chlorpromazine. - As adjuvant with selective serotonin reuptake inhiitors (SSRIs) in anxiety.