Pharmacology: First-Generation Antihistamines - Diphenhydramine

These flashcards cover essential information about the first-generation antihistamine diphenhydramine, including its therapeutic uses, side effects, contraindications, precautions, administration, and client instructions.

Therapeutic Use of Diphenhydramine

Management of mild allergic reactions, anaphylaxis, motion sickness, and short-term insomnia.

Adverse Drug Reactions of Diphenhydramine

Drowsiness, dizziness, and anticholinergic effects such as dry mouth and constipation.

Precautions for Diphenhydramine

Use with caution in children, older adults, individuals with asthma history, urinary retention, open-angle glaucoma, hypertension, and impaired kidney or liver function.

Contraindications for Diphenhydramine

Not recommended for newborns, children under 2 years, breastfeeding women, those with narrow-angle glaucoma, prostatic hypertrophy, or during acute asthma exacerbation.

Administration Instructions for Diphenhydramine

Do not crush or chew enteric-coated formulations. Take 30 min to 2 hr before activity for motion sickness, and avoid alcohol or other CNS depressants.

Client Instructions for Diphenhydramine

Take medication at bedtime or before required activities, increase fluid and fiber intake, report difficulty urinating.

Monitoring for Diphenhydramine

Monitor client while ambulating and for urinary retention, and advise against driving or operating machinery.