acetaminophen/doxylamine/dextromethorphan (OTC)

Frequency Not Defined

Angioedema

Laryngeal edema

Dizziness

Drowsiness

Pruritic maculopapular rash

Urticaria

Dry mouth, throat, and nose

Agranulocytosis

Leukopenia

Neutropenia

Pancytopenia

Thrombocytopenia

Thrombocytopenic purpura

Hepatotoxicity

Thickening of mucus in nose or throat

Anaphylactoid reaction

Contraindications

Hypersensitivity

Asthma

Narrow-angle glaucoma

Symptomatic prostate hypertrophy

Bladder-neck obstruction

Stenosing peptic ulcer

G-6-PD deficiency

Severe hepatic impairment

Cautions

Acetaminophen hepatotoxicity possible in chronic alcoholics following various dose levels

Severe or recurrent pain or high or continued fever may indicate a serious illness

Acetaminophen contained in many OTC products and combined use with these products may result in toxicity due to cumulative doses exceeding recommended maximum dose

Acetaminophen: Risk for rare, but serious skin reactions that can be fatal; these reactions include Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP); symptoms may include skin redness, blisters and rash

Doxylamine may exacerbate angle closure glaucoma, hyperthyroidism, peptic ulcer, or urinary tract obstruction; xerostomia may occur

Do not take dextromethorphan for persistent or chronic cough associated with smoking, asthma, or emphysema, or if it is accompanied by excessive phlegm unless directed by a healthcare provider; dextromethorphan may slow the breathing

Pregnancy category: C

Lacation: excreted in breast milk, use caution

Pregnant or breastfeeding patients should seek advice of health professional before using OTC drugs

Pregnancy Categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

Mechanism of Action

Acetaminophen: Blocks pain impulse generation peripherally and may inhibit prostaglandin generation in CNS; reduces fever by inhibiting hypothalamic heat-regulating center

Doxylamine: Competitively blocks histamine from binding to H1 receptors; significant antimuscarinic activity and penetrates CNS, which causes pronounced tendency to induce sedation

Dextromethorphan: Cough suppressant that acts centrally on cough center in medulla