carbinoxamine

General

**BEERS Drug**

Pronunciation:
car-bi-nox-a-meen

Trade Name(s)

• Karbinal ER

Ther. Class.
allergy, cold and cough remedies
none assigned

Pharm. Class.
antihistamines

Indications

• Seasonal and perennial allergic rhinitis.
• Vasomotor rhinitis.
• Allergic conjunctivitis due to inhalant allergens and foods.
• Mild, uncomplicated allergic skin manifestations of urticaria and angioedema.
• Dermatographism.
• Anaphylaxis (as adjunct to epinephrine after acute manifestations controlled).
• Allergic reactions to blood or plasma.

Action

Antagonizes the effects of histamine at H₁ –receptor sites; does not bind to or inactivate histamine. Significant CNS depressant and anticholinergic properties.

Therapeutic Effect(s):

Decreased symptoms of histamine excess (sneezing, rhinorrhea, nasal/ocular pruritus, ocular tearing/redness and skin itching/urticaria).

Pharmacokinetics

Absorption: Well absorbed following oral administration

Distribution: Unknown

Metabolism and Excretion: Extensively metabolized by the liver, inactive metabolites excreted in urine. Negligible renal elimination of unchanged drug.

Half-life: 17 hr

TIME/ACTION PROFILE (plasma concentrations)

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity, including sulfite allergy
• Lactation: Lactation (risk of death in children <2 yr);
• Concurrent use of MAO inhibitors
• Pedi:   Children <2 yr (deaths have been reported).

Use Cautiously in:

• Increased intraocular pressure or narrow angle glaucoma
• Hyperthyroidism
• Cardiovascular disease including hypertension
• Stenosing peptic ulcer or pyloroduodenal obstruction
• Symptomatic prostatic hypertrophy or bladder neck obstruction
• OB:  Safety not established in pregnancy
• Pedi:  Younger children may be more sensitive to sedation or excitation
• Geri:  Older adults may be more susceptible to adverse reactions.

Adverse Reactions/Side Effects

Resp: thickened bronchial secretions

GI: epigastric distress

Neuro: disturbed coordination, dizziness, drowsiness, sedation

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

• Concurrent use with  MAO inhibitors  may ↑ anticholinergic effects.
• ↑ risk of CNS depression with other  CNS depressants  including  alcohol, other  antihistamines ,  opioid analgesics  and  sedative/hypnotics.

Route/Dosage

PO (Adults and Children ≥ 12 yr): Immediate-release tablets or solution– 4–8 mg 3–4 times daily;  Extended-release suspension– 6–16 mg every 12 hr.

PO (Children 6–11 yr): Immediate-release tablets or solution– 2–4 mg 3–4 times daily;  Extended-release suspension– 6–12 mg every 12 hr.

PO (Children 4–5 yr): Immediate-release solution– 1–2 mg 3–4 times daily;  Extended-release suspension– 3–8 mg every 12 hr.

PO (Children 2–3 yr): Immediate-release solution– 1–2 mg 3–4 times daily;  Extended-release suspension– 3–4 mg every 12 hr.

Availability (generic available)

Immediate-release tablets: 4 mg

Immediate-release oral solution (banana bubble gum flavor): 4 mg/5 mL

Extended-release oral suspension (contains metabisulfite) (strawberry banana flavor): 4 mg/5 mL

Assessment

• Assess allergy symptoms (rhinitis, conjunctivitis, hives) before and periodically during therapy
• Assess lung sounds and character of bronchial secretions. Maintain fluid intake of 1500–2000 mL/day to decrease viscosity of secretions

Lab Test Considerations:

May case ↑ uric acid levels.

Potential Diagnoses

• Ineffective airway clearance (Indications) 
• Risk for injury (Adverse Reaction) 

Implementation

• Begin with lowest dose and increase as needed and tolerated. Dose is based on condition severity and patient response.
• PO 

  Administer twice daily.

  • Use a calibrated measuring device for accurate dose; household tablespoon is not accurate and could lead to overdose. May be fatal if administered to children under 2 yr.

Patient/Family Teaching

• Instruct patient to take medication as directed
• May cause dizziness and drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known
• Advise patient to avoid taking alcohol or other CNS depressants concurrently with this drug
• Advise patient that good oral hygiene, frequent rinsing of mouth with water, and sugarless gum or candy may minimize dry mouth. Patient should notify dentist if dry mouth persists >2 wk
• Rep:  Instruct females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding. Monitor infants breastfeeding mothers taking carbinoxamine for drowsiness and irritability.

Evaluation/Desired Outcomes

Decrease in allergic symptoms