acetaminophen/doxylamine/dextromethorphan/pseudoephedrine (Vicks NyQuil D, Vicks NyQuil)

Dosing and uses of Vicks NyQuil D, Vicks NyQuil (acetaminophen/doxylamine/dextromethorphan/pseudoephedrine)

• Adult
• Pediatric

 

Adult dosage forms and strengths

acetaminophen/doxylamine/dextromethorphan/pseudoephedrine

liquid

• (325mg/6.25mg/15mg/30mg)/15mL

 

Nasal Congestion, Rhinorrhea, Sore Throat, Cough, Fever, Headache

30 mL PO q6-8hr; not to exceed 4 doses/day

 

Pediatric dosage forms and strengths

acetaminophen/doxylamine/dextromethorphan/pseudoephedrine

liquid

• (325mg/6.25mg/15mg/30mg)/15mL

 

Nasal Congestion, Rhinorrhea, Sore Throat, Cough, Fever, Headache

Vicks NyQuil d

• <12 years old: Ask a pediatrician
• >12 years old: 30 mL PO q6-8hr; not to exceed 4 doses/day

 

Vicks NyQuil D, Vicks NyQuil (acetaminophen/doxylamine/dextromethorphan/pseudoephedrine) adverse (side) effects

Frequency not defined

Arrhythmia

Palpitations

Convulsion

Dizziness

Drowsiness

Excitability

Tremor

Weakness

Dermatologic rash

GI disturbances

Anemia blood dyscrasias (neutropenia, pancytopenia, leukopenia)

Bilirubin and alkaline phosphatase may increase

Dry mouth, throat, and nose

Thickening of mucus in nose or throat

 

Warnings

Contraindications

Hypersensitivity to any of the drugs

Asthma

Narrow-angle glaucoma

<2 years of age

Symptomatic prostate hypertrophy

Use of MAO inhibitors within 14 days

Severe hypertension

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

Dextromethorphan: Do not take 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; may slow respiration rate

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

Pseudoephedrine: Caution in cardiovascular disease, diabetes mellitus, prostatic hypertrophy and increased intraocular pressure

 

Pregnancy and lactation

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.

 

Pharmacology of Vicks NyQuil D, Vicks NyQuil (acetaminophen/doxylamine/dextromethorphan/pseudoephedrine)

Mechanism of action

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

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

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

Pseudoephedrine: Stimulates the alpha-adrenergic receptors causing bronchodilation & vasoconstriction

 

Acetaminophen

Peak plasma time: 10-60 min (PO immediate release); 60-120 min (PO extended release); 6 hr (PO 500 mg tablet); 8 hr (PO 650 mg extended release tablet)

Vd: 1 L/kg

Protein binding: 10-25%

Metabolism: Liver (microsomal enzyme systems); conjugation (glucuronic acid)

Half-life: 1.25-3hr

Excretion: Urine

 

Dextromethorphan

Onset: 15-30 min

Duration: 3-6 hr

Metabolism: Hepatic P450 enzyme CYP2D6

Excretion: Urine

Half-life: 2-4 hr (extensive metabolizers); 24 hr (poor metabolizers)

Peak plasma time: 2-3 hr

 

Doxylamine

Peak plasma time: 2-3 hr

Half-life: 10-12 hr

Excretion: Urine

Metabolism: Liver (CYP450)

 

Pseudoephedrine

Half-Life: 3 hr (children); 9-16 hr (adults)

Onset: 30 min (decongestant)

Duration: 3-8 hr  

Peak Plasma

Time: 1.97 hr

Concentration: 422 ng/mL

Metabolism: Liver, by N-demethylation

Metabolites: Inactive

Clearance: 7.3-7.6 mL/min/kg

Excretion: Urine (43-96%)