Week 6: Antihistamines 1st generation: Upper Respiratory Meds

Question 1

Antihistamine 1st Generation Drug

Answer 1

diphenhydramine

Question 2

Expected Pharmacologic Action

Answer 2

• work on H2 receptor blocking histamine release in the small blood vessels, capillaries, and nerves
• relieve itching, sneezing, and rhinorrhea
• do not relieve nasal congestion

Question 3

Therapeutic Use

Answer 3

• allergic reactions (seasonal allergic rhinitis, urticaria, mild transfusion reactions)
• relieve itching, sneezing, and rhinorrhea
• anaphylaxis (hypotension, acute laryngeal edema, bronchospasms)
• motion sickness
• insomnia

Question 4

Complications

Answer 4

• produce cholinergic effects and drowsiness
• sedation
• GI discomfort
• acute toxicity, excitation, hallucinations, incoordination and seizures in children

Question 5

Contraindications

Answer 5

• pregnancy risk category B
• contraindicated during third trimester of pregnancy, for clients who are breastfeeding, and for newborns (sensitive to sedation effects)
• use cautiously in clients who have asthma. seizure disorder, cardiac disease, renal disease, urinary retention, open-angle glaucoma, hypertension, and prostate hypertrophy
• cautiously in children and older adults

Question 6

Medication Administration

Answer 6

• take with food
• take sips of water
• take at night to minimize daytime sedative effects

Question 7

Nursing Interventions

Answer 7

• avoid alcohol and other CNS depressants
• administer activated charcoal and cathartic to decrease absorption of antihistamine
• administer acetaminophen (Tylenol) for fever
• apply ice packs or sponge bath

Question 8

Client Education

Answer 8

• beware of sedating effects

- avoid alcohol and medications causing CNS depression (opioids, barbiturates, benzodiazepines)

Question 9

Evaluation of Medication Effectiveness

Answer 9

• improvement of allergic reaction (absence of rhinitis, urticaria)
• relief of motion sickness (decreased nausea and vomiting)