Himalayan College of Nursing

Presenter: Mr. Muthuvenkatachalam S., D.Pharm, M.Sc (AIIMS), PhD Scholar (RGUHS)

Antipsychotic agents

Classification• Typical antipsychotics• Phenothiazines

– Chlorpromazine: 40-800 mg– Perphenazine: 12-64 mg– Fluphenazine: 1-40 mg– Thioridazine: 150-800 mg

• Thioxanthenes– Thiothixene: 6-30 mg

• Butyrophenones– Haloperidol: 1-100 mg

• Dibenzothiazepine– Quetiapine: 150-750 mg

Atypical antipsychotics Clozapine: 300-900 mgRisperidone: 4-16 mgOlanzapine: 5-20 mg

Indications

• Acute and chronic psychoses, particularly when accompanied by increased psychomotor activity.

• Selected agents used as antiemetics (Chlorpromazine, perpohenazine, prochlorperazine)

• Interactable hiccoughs (chlorpromazine, perphenazine)

• Tics and vocal utterances in Tourette’s disorder (haloperiod, pimozide)

Action

• The exact mechanism is not known.• Blocking postsynaptic dopamine receptors in

the basal ganglia, hypothalamus, limbic system, brainstem, and medulla.

• Newer medications may exert antipsychotic properties by blocking action on receptors specific to dopamine, sertonin, and other neurotransmitters.

• Inhibition of Dopamine mediated transmission of neural impulses

Contraindications• Known hypersensitity• Should not be used when CNS depression is

evident.• Blood dyscrasias• Parkinson’ disease• Liver/renal/cardiac insufficiencies.Caution:• Elderly, severely ill or debilitated• Diabetic, respiratory insufficiency, prostatic

hypertrophy, or intestinal obstruction.• Safety in pregnancy and lactation has not been

established.

Interactions• Additive anticholinergic effects are observed when

antipsychotics are taken concurrently with other drugs that produce these properties.

• Additive hypotensive effect with beta-adrenergic blockers.

• Antacids and antidiarrheals may decrease absoption of antipsychotics.

• Barbiturates may increase metabolism and decrease effectiveness of antipsychotics.

• Additive CNS depression with alcohol, sedative hypnotics and anxiolytics.

Nsg diagnosis

• Risk for other-directed violence related t panic anxiety and mistrust of others.

• Risk for injury related medication side effects• Risk for activity intolerance related to

medication side effects of sedation, blurred vision and weakness

• Noncompliance with medication regimen related to suspiciousness and mistrust of others.

Side effects

• Anticholinergic effects– Dry mouth– Blurred vision– Constipation– Urinary retention

• Nausea• Skin rash• Sedation• Orthostatic hypotension• Photosensitivity• Hormonal effects

– Decreased libido, retrograde ejaculation, gynecomastia, Amenorrhea, weight gain.

Side effects (contd..)

• ECG changes: prolongation of the QT interval, are possible with most of the antipsychotics.– Caution: patient with arrhythmias

• Reduction of seizure threshold.• Agranulocytosis

– Clozapine: weekly/biweekly blood investigation.

• Hypersalivation (clozapine)

Extrapyramidal symptoms (EPS)• Pseudoparkinsonism

– Tremor, shuffling gait, drooling, rigidity.– 1-5 days after initiation of antipsychotics

• Akinesia• Akathisia (50-60 days after initiation of therapy)• Dystonia

– Men; <25• Oculogyric crisis

– Treated as emergency– Physician should be contacted immediately– IV benztropine mesyulate

• Tardive dyskinesia

Side effects (contd..)

• Neuroleptic malignant syndrom (NMS)– Severe parkinsonian muscle ridigidity– Upto 1070C, tachycardia, tachypnea– Fluctuations in blood pressure, diaphoresis, and

rapid deterioration of mental status to stupor and coma.

– This is rare but potentially fatal complication of treatment with neuroleptic drugs.

– Within hours – year after drug initiation.]– Discontinue neuroleptic immediately.– Bromocryptine or dantrolene

Antiparkinsonian agents

• Anticholinergics– Benztropine: 0.5-9mg– Biperiden: 2-8 mg– Procyclidine: 5-20 mg– Trihexyphenidyl: 1-15 mg

• Antihistamines:– Diphenhydramine: 10-400 mg

• Dopaminergic agents: – Amantadine: 200-400 mg– Bromocriptine: 10-40 mg

Indications

• Indicated for the treatment of all forms of parkinsonism and for the relief of drug-induced extrapyramidal reactions.

Actions

• Restoring the natural balance of two major neurotransmitters in the CNS: Ach, Dopamine.

• Deficiency in dopamine results in excessive cholinergic activity.

• Anticholinergics or dopaminergic agonists.

Contraindications/precautions• Hypersensitity• Angle-closure glaucoma• Pyloric or duodenal obstruction• Peptic ulcers,• Prostatic hypertrophy• Bladder neck obstruction, megacolon.• Myasthenia gravis.Caution

– Tachycardia, cardiac arrhythmias, hypertension, hypotension, and tendency toward urinary retention.

– Elderly, hepatic/renal/cardiac insufficiency

Side effects

• Anticholinergic effects– Dry mouth, blurred vision, constipation,

paralytic ileus, Urinary retention, tachycardia• Nausea, GI upset• Sedation, drowsiness, dizziness.• Exacerbation of psychoses.• Orthostatic hypotension.