Home Drug Guide Pyrilamine Maleate

Drug Guide

Generic Name

Pyrilamine Maleate

Brand Names

Classification

Therapeutic: Antihistamine

Pharmacological: H1 antihistamine

FDA Approved Indications

N/A

Mechanism of Action

Pyrilamine Maleate is an H1 histamine receptor antagonist that blocks the effects of histamine at H1 receptor sites, thereby reducing allergic responses.

Dosage and Administration

Adult: Dosage varies; typically 25-50 mg orally every 4-6 hours as needed, not exceeding 300 mg/day.

Pediatric: Use with caution; dosage is usually 1 mg/kg body weight per day divided into multiple doses.

Geriatric: Start at lower doses due to increased sensitivity and risk of adverse effects.

Renal Impairment: Adjust dosage based on renal function; consult prescribing information.

Hepatic Impairment: Use caution; no specific guidelines, monitor for efficacy and toxicity.

Pharmacokinetics

Absorption: Rapidly absorbed from the gastrointestinal tract.

Distribution: Widely distributed; crosses the blood-brain barrier, causing sedation.

Metabolism: Metabolized in the liver.

Excretion: Excreted primarily in urine.

Half Life: Approx. 4-6 hours.

Contraindications

Hypersensitivity to pyrilamine or similar antihistamines.
Use caution in patients with glaucoma, urinary retention, hypertension, or cardiovascular disease.

Precautions

Use with caution in elderly, children, and those with central nervous system depression.

Adverse Reactions - Common

Sedation, drowsiness (Common)
Dry mouth, dizziness (Common)

Adverse Reactions - Serious

CNS depression, respiratory depression (Rare)
Allergic reactions including rash, urticaria (Rare)

Drug-Drug Interactions

CNS depressants, alcohol, other sedatives

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for sedative effects, allergic reactions, and anticholinergic side effects.

Diagnoses:

Risk for falls in elderly due to sedation or dizziness.
Altered sleep pattern related to sedative effects.

Implementation: Administer with food to reduce gastrointestinal upset; educate patients about sedation and safety measures.

Evaluation: Assess symptom relief and monitor for adverse effects.

Patient/Family Teaching

Take medication exactly as prescribed.
Avoid activities requiring alertness until response is known.
Do not consume alcohol or CNS depressants without consulting healthcare provider.
Report excessive drowsiness, allergic reactions, or other side effects.

Special Considerations

Black Box Warnings:

CNS depression, especially in elderly, young children, or if combined with other CNS depressants.

Genetic Factors: Not specifically linked to genetic testing.

Lab Test Interference: None known.

Overdose Management

Signs/Symptoms: Severe drowsiness, hallucinations, seizures, respiratory depression.

Treatment: Supportive care, ensure airway patency, administer activated charcoal if within appropriate time frame, and provide symptomatic treatment.

Storage and Handling

Storage: Store at room temperature away from moisture, light, and heat.

Stability: Stable under proper storage conditions.