carbinoxamine

General

Pronunciation:
car-bi-nox-a-meen

Trade Name(s)

• Karbinal ER

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

Pharm. Class.
antihistamines

Indications

Relief of allergic symptoms caused by histamine release including seasonal/perennial allergic rhinitis, vasomotor rhinitis, allergic conjunctivitis (due to inhalant allergens or foods), mild/uncomplicated allergic skin conditions (urticaria or angioedema), dermatographism, as adjunctive management (with epinephrine and other standard acute treatments) of anaphylaxis, and to decrease severity of allergic reactions to blood/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: Unk

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

Half-life: 17 hr

TIME/ACTION PROFILE (antihistaminic effects)

Contraindication/Precautions

Contraindicated in:

• Hypersensitivity, including sulfite allergy
• Lactation: Avoid if breast-feeding (risk of death in infant);
• Concurrent use of MAOIs
• 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
• Geri: Elderly may be more susceptible to adverse reactions;
• OB: Use in pregnancy only if clearly needed
• Pedi: Younger children may be more sensitive to sedation or excitation.

Adverse Reactions/Side Effects

CNS: dizziness, drowsiness, sedation

Resp: thickened bronchial secretions

GI: epigastric distress

Neuro: disturbed coordination

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

Interactions

Drug-Drug

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

Route/Dosage

Use appropriate measuring device

PO (Adults and Children) ≥ 12 yr) 6–16 mg (7.5–20 mL) every 12 hr.

PO (Children 2–11 yr) 0.2–0.4 mg/kg/day in divided doses every 12 hr; Children 6–11 yr–6–12 mg (7.5–15 mL) every 12 hr; Children 4–5 yr–3–8 mg (3.75–10 mL) every 12 hr; Children 2–3 yr–3–4 mg (3.75–5 mL) every 12 hr.

Availability

Extended-release oral suspension (contains metabisulfite) (strawberry banana): 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.

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
• Instruct female patient to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes

Decrease in allergic symptoms