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    DEA Class;  (OTC)

    Common Brand Names; ChlorTrimeton, Diabetic Tussin

    • Antihistamines, 1st Generation

    Histamine H1-receptor antagonist in blood vessels, respiratory tract, and gastrointestinal tract

    Indicated for the treatment of Allergic Rhinitis

    Perennial & seasonal allergic & vasomotor rhinitis, relief of symptoms from colds, urticaria, angioedema, anaphylactic reactions, pruritus, allergic conjunctivitis


    Documented hypersensitivity

    Lower respiratory disease, eg, asthma (controversial)

    Preemies & neonates

    Nursing women

    Acute asthma, sleep apnea

    Varies in incidence & severity with the individual drug; also individual patients vary in susceptibility

    • CNS depression
    • Drowsiness
    • Sedation ranging from mild drowsiness to deep sleep (most frequent)
    • Dizziness
    • Lassitude
    • Disturbed coordination
    • Muscular weakness
    • Restlessness, insomnia, tremors, euphoria, nervousness, delirium, palpitation, seizures is less common
    • Epigastric distress
    • Anorexia
    • Nausea
    • Vomiting
    • Diarrhea
    • Constipation

    Caution in narrow angle glaucoma, prostatic hypertrophy, stenosing peptic ulcer, pyloroduodenal obstruction, or bladder neck obstruction

    Chlor Trimeton non-drowsy contains no chlorpheniramine, only pseudoephedrine

    All injections discontinued

    Antihistamine exposure in first trimester not reported to be associated with increased risk of malformations; animal studies not reported; there are no controlled data in human pregnancy; only recommended for use during pregnancy when benefit outweighs risk

    Excretion into human milk; the manufacturer recommends that caution be used when administering chlorpheniramine to nursing women

    Allergic Rhinitis

    Tablets or syrup: 4 mg PO q4-6hr; not to exceed 24 mg/day

    Extended-release tablets: 8 mg PO q8-12hr or 12 mg q12hr; not to exceed 24 mg/day

    Extended-release capsules: 12 mg PO qDay; not to exceed 24 mg/day

    Sustained-release capsules: 8-12 mg PO q8-12hr, up to 16-24 mg/day



    • 4mg
    • 8mg
    • 12mg


    • 2mg/5mL