cetirizine hydrochloride


cetirizine hydrochloride

All-Day Allergy, Aller-Relief, Allergy Relief, Benadryl Allergy Oral Solution (UK), Benadryl One a Day (UK), Piriteze (UK), Pollenshield Hayfever (UK), Reactine, Zirtec (UK), Zyrtec

Pharmacologic class: Histamine1-receptor antagonist (peripherally selective)

Therapeutic class: Allergy, cold, and cough agent; antihistamine

Pregnancy risk category B

Action

Antagonizes histamine's effects at histamine1-receptor sites, preventing allergic response. Also has mild bronchodilatory effects and blocks histamine-induced bronchoconstriction in asthma.

Availability

Syrup: 5 mg/5 ml

Tablets: 5 mg, 10 mg

Indications and dosages

➣ Allergic symptoms caused by histamine release
Adults and children older than age 6: 5 to 10 mg P.O. daily
Children ages 2 to 5: 2.5 to 5 mg P.O. daily

Dosage adjustment

• Renal impairment

• Hepatic impairment

Contraindications

• Hypersensitivity to drug or hydroxyzine

• Acute asthma attacks

• Angle-closure glaucoma

• Pyloroduodenal obstruction

• Breastfeeding

Precautions

Use cautiously in:

• renal impairment, significant hepatic dysfunction

• elderly patients

• pregnant patients

• children younger than age 2 (safety not established).

Administration

• Give with or without food.

• Administer at same time each day.

Adverse reactions

CNS: dizziness, drowsiness, fatigue

CV: palpitations, edema

EENT: pharyngitis

GI: nausea, vomiting, abdominal distress, dry mouth

Musculoskeletal: myalgia, joint pain

Respiratory: bronchospasm

Skin: photosensitivity, rash, angioedema

Other: fever

Interactions

Drug-drug. CNS depressants: additive CNS effects

Theophylline: decreased cetirizine clearance

Drug-diagnostic tests. Allergy skin tests: false-negative results

Drug-behaviors. Alcohol use: additive CNS effects

Sun exposure: photosensitivity

Patient monitoring

• Monitor creatinine levels in patients with renal dysfunction.

• Assess hepatic enzyme levels in patients with hepatic disease.

Patient teaching

• Tell patient to take with full glass of water.

• Inform patient that drug may impair alertness and that alcohol may exaggerate this effect.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.