Home Drug Guide Bromodiphenhydramine Hydrochloride

Drug Guide

Generic Name

Bromodiphenhydramine Hydrochloride

Brand Names Ambodryl

Classification

Therapeutic: Antihistamine, Anticholinergic

Pharmacological: H1-antihistamine, Anticholinergic

FDA Approved Indications

  • Allergic rhinitis
  • Seasonal allergic conjunctivitis
  • Urticaria (hives)

Mechanism of Action

Bromodiphenhydramine is an H1 antihistamine that blocks the effects of histamine at H1 receptor sites, reducing allergy symptoms. Its anticholinergic properties also contribute to drying effects such as reduced mucus secretion.

Dosage and Administration

Adult: Typically 25-50 mg every 4-6 hours as needed, not exceeding 300 mg/day

Pediatric: Dosage varies by age; generally 6-12 mg every 4-6 hours, not exceeding 12 mg/kg/day or as directed by physician

Geriatric: Start with lower doses due to increased sensitivity; monitor for anticholinergic side effects and sedation

Renal Impairment: Adjust dosing based on severity of impairment; consult specific guidelines

Hepatic Impairment: Use with caution; dose adjustments may be necessary depending on hepatic function.

Pharmacokinetics

Absorption: Well absorbed following oral administration

Distribution: Widely distributed including into tissues and body fluids

Metabolism: Metabolized in the liver (CYP450 pathway)

Excretion: Excreted primarily in urine, both as metabolites and unchanged drug

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

Contraindications

  • Known hypersensitivity to bromodiphenhydramine or other antihistamines
  • Newborns and premature infants

Precautions

  • Use with caution in patients with glaucoma, urinary retention, prostatic hypertrophy, or gastric retention; avoid in patients with asthma or COPD without medical advice; caution in elderly due to anticholinergic effects

Adverse Reactions - Common

  • Sedation or drowsiness (Common)
  • Dry mouth (Common)
  • Dizziness (Uncommon)

Adverse Reactions - Serious

  • Seizures (rare) (Rare)
  • Cardiac arrhythmias (rare) (Rare)
  • Allergic reactions including rash, pruritus (rare) (Rare)

Drug-Drug Interactions

  • Additive sedative effects with other CNS depressants (e.g., alcohol, benzodiazepines)
  • Anticholinergic drugs may enhance anticholinergic side effects

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor for effectiveness in relieving allergy symptoms; assess mental status, sedation levels, and respiratory status

Diagnoses:

  • Risk for sedation and falls
  • Impaired comfort related to allergy symptoms

Implementation: Administer with food if gastrointestinal upset occurs; instruct patient to avoid activities requiring alertness until response is known

Evaluation: Assess symptom relief and monitor for adverse effects regularly

Patient/Family Teaching

  • Take medication exactly as prescribed; do not exceed recommended doses.
  • Warn about possible drowsiness; avoid driving or operating heavy machinery until response is known.
  • Caution to avoid alcohol and other CNS depressants.
  • Report any signs of allergic reactions, severe side effects, or unusual symptoms.

Special Considerations

Black Box Warnings:

  • None specific to this medication

Genetic Factors: Pharmacogenetic variations may influence metabolism and response

Lab Test Interference: None known

Overdose Management

Signs/Symptoms: Seizures, hallucinations, pupil dilation, dry mouth, flushing, tachycardia, urinary retention, hypotension, hallucinations, coma

Treatment: Supportive care; activated charcoal if ingestion is recent; intravenous fluids; management of agitation or seizures; cardiac monitoring

Storage and Handling

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

Stability: Stable for the duration of the expiration date when properly stored

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.