Home Drug Guide Propiomazine Hydrochloride

Drug Guide

Generic Name

Propiomazine Hydrochloride

Brand Names Largon

Classification

Therapeutic: Antipsychotic, Sedative

Pharmacological: Phenothiazine derivative

FDA Approved Indications

Short-term treatment of insomnia in adults

Mechanism of Action

Propiomazine acts primarily as an antihistamine with sedative properties. It exerts its effects by blocking H1 histamine receptors in the brain, and may have some anticholinergic and sedative effects due to its phenothiazine structure.

Dosage and Administration

Adult: 25-50 mg at bedtime; maximum 100 mg/day

Pediatric: Not typically recommended for children due to safety concerns

Geriatric: Start at lower doses, e.g., 25 mg at bedtime, and adjust carefully due to increased sensitivity

Renal Impairment: Use with caution, consider dose reduction

Hepatic Impairment: Use with caution; liver function may affect metabolism and clearance

Pharmacokinetics

Absorption: Well absorbed after oral administration

Distribution: Widely distributed throughout the body, crosses the blood-brain barrier

Metabolism: Metabolized in the liver, primarily via hepatic enzymes

Excretion: Excreted mainly in urine

Half Life: Approximately 10-12 hours, may be prolonged in elderly or hepatic impairment

Contraindications

Severe CNS depression
ComA intolerances to phenothiazines

Precautions

Use with caution in elderly due to potential for sedation and falls, patient with liver impairment, history of seizure disorders, or history of Parkinson's disease

Adverse Reactions - Common

Sedation (Common)
Dizziness (Common)
Dry mouth (Common)

Adverse Reactions - Serious

Extrapyramidal symptoms (Uncommon)
Hypotension (Uncommon)
QT prolongation, arrhythmias (Rare)

Drug-Drug Interactions

Alcohol, CNS depressants (additive sedation), Anticholinergic agents (increased anticholinergic effects)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for excessive sedation, respiratory status, mental status, and involuntary movements

Diagnoses:

Risk for falls due to sedation
Impaired sleep pattern

Implementation: Use lowest effective dose, advise to avoid alcohol and CNS depressants, assess sleep pattern and side effects

Evaluation: Efficacy in reducing sleep disturbances and monitoring adverse effects

Patient/Family Teaching

Take medication exactly as prescribed, preferably before bedtime
Avoid alcohol and CNS depressants
Report any excessive drowsiness, unusual movements, or cardiovascular symptoms
Do not operate heavy machinery until sedative effects are known

Special Considerations

Black Box Warnings:

Potential for serious adverse effects including respiratory depression in overdose

Genetic Factors: Metabolism may vary with CYP2D6 polymorphisms

Lab Test Interference: None significant

Overdose Management

Signs/Symptoms: Excess sedation, hallucinations, seizures, respiratory depression, hypotension, extrapyramidal symptoms, arrhythmias

Treatment: Supportive care, activated charcoal if early, IV fluids, monitoring cardiac status, airway management, symptomatic treatment, and measures to control seizures if they occur

Storage and Handling

Storage: Store at room temperature away from light and moisture

Stability: Stable within the expiration date when properly stored