acetaminophen/dextromethorphan/phenylephrine (Alka-Seltzer Plus Day Cold, Theraflu Daytime Severe Cold and Cough, Tylenol Cold Multi-Symptom Daytime, Tylenol Cold Head Congestion Daytime, Vicks DayQuil Cold/Flu, Alka-Seltzer Plus Day Severe Cold, Cough and Flu, Alka-Seltzer Plus Day Sinus Congestion, Allergy and Cough, Alka-Seltzer Plus Severe Sinus Congestion and Cough)

Dosing and uses of Alka-Seltzer Plus Day Cold, Theraflu Daytime Severe Cold and Cough (acetaminophen/dextromethorphan/phenylephrine)

• Adult
• Pediatric

 

Adult dosage forms and strengths

acetaminophen/dextromethorphan/phenylephrine

caplet

• 325mg/10mg/5mg

rapid release gelcap

• 325mg/10mg/5mg

capsule

• 325mg/10mg/5mg

oral solution

• (80mg/2.5mg/1.25mg)/1mL

oral suspension

• (160mg/5mg/2.5mg)/5 mL

liquid

• (325mg/10mg/5mg)/15mL

powder for solution

• (650mg/20mg/10mg)/packet

syrup

• (325mg/10mg/5mg)/15mL

 

Symptomatic Relief of Cough & Congestion

1 packet PO q4hr; not to exceed 6 doses/day

2 caplets/capsules PO q4hr; not to exceed 12 caplets/capsules/day

30 mL liquid/syrup PO q4hr; not to exceed 6 doses (12 tablespoons)/day

2 gelcaps q4hr; not to exceed 12 gelcaps/day

 

Pediatric dosage forms and strengths

acetaminophen/dextromethorphan/phenylephrine

tablet

• 325mg/10mg/5mg
• 162.5mg/5mg/2.5mg
• 250mg/10mg/5mg

rapid release gelcap

• 325mg/10mg/15mg

capsule

• 325mg/10mg/5mg

liquid

• (325mg/10mg/5mg/)30/mL
• (160mg/5mg/2.5mg)/5mL

 

Symptomatic Relief of Cough & Congestion

<4 Years Old

• Not recommended

4-6 Years (36-47 lb)

• Oral suspension: 5 mL PO q4hr; not to exceed 25 mL/day
• Oral solution: 2 mL PO q4hr PRN; not to exceed 12 mL/day

6-12 Years Old

• Oral suspension: 10 mL PO q4hr; not to exceed 50 mL/day
• Oral solution: 4 mL PO q4hr PRN; not to exceed 24 mL/day

>12 Years Old

• 1 packet PO q4hr; not to exceed 6 doses/day
• 2 caplets/capsules PO q4hr; not to exceed 12 caplets/capsules/day
• 30 mL liquid/syrup PO q4hr; not to exceed 6 doses (12 tablespoons)/day
• 2 gelcaps q4hr; not to exceed 12 gelcaps/day

 

Barbiturates, carbamazepine, hydantoins, isoniazid, and rifampin may increase the hepatotoxic potential of acetaminophen and may decrease the analgesic effects of acetaminophen; cholestyramine may decrease acetaminophen absorption

Quinidine may inhibit the metabolism of dextromethorphan increasing its toxicity (adjust dose); concurrent use of dextromethorphan with MAO inhibitors may cause hyperpyrexia, abnormal muscle movement, hypotension, coma, and death (avoid use for 2 weeks after stopping the MAO inhibitor; coadministration of dextromethorphan with sibutramine may cause serotonin syndrome (concomitant use not recommended)

Guanethidine may increase pressor response of direct-acting vasopressors, like phenylephrine, possibly resulting in severe hypertension

 

Alka-Seltzer Plus Day Cold, Theraflu Daytime Severe Cold and Cough (acetaminophen/dextromethorphan/phenylephrine) adverse (side) effects

Frequency not defined

Hypertension

Reflex tachycardia

Severe peripheral and visceral vasoconstriction

Dizziness

Drowsiness

Excitability

Headache

Restlessness

Tremor

GI disturbances

Anemia blood dyscrasias (neutropenia, pancytopenia, leukopenia)

Bilirubin and alkaline phosphatase may increase

 

Warnings

Contraindications

Documented hypersensitivity to the drugs

Within 14 days of MAO inhibitor therapy; known G-6-PD deficiency

 

Cautions

Caution in elderly patients, hyperthyroidism, myocardial disease, bradycardia, partial heart block or severe arteriosclerosis when administering phenylephrine; in hypovolemia, phenylephrine use is not a substitute for replacement of blood, fluids and electrolytes, and plasma (promptly restore with loss); dilute IV and administer via large vein; extravasation precautions required

Acetaminophen hepatotoxicity possible in chronic alcoholics following various dose levels; severe or recurrent pain or high or continued fever may indicate a serious illness; contained in many OTC products and combined use with these products may result in toxicity due to cumulative doses exceeding recommended maximum dose

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

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

 

Pregnancy and lactation

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 Alka-Seltzer Plus Day Cold, Theraflu Daytime Severe Cold and Cough (acetaminophen/dextromethorphan/phenylephrine)

Mechanism of action

Acetaminophen blocks pain impulse generation peripherally and may inhibit the generation of prostaglandin in the CNS. Reduces fever by inhibiting the hypothalamic heat-regulating center.

Dextromethorphan is a cough suppressant that acts centrally on the cough center in the medulla.

Pseudoephedrine stimulates the alpha-adrenergic receptors causing bronchodilation and vasoconstriction.

 

Pharmacokinetics

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

Phenylephrine

• Half-life: 2-3 hr
• Onset: 10-15 min
• Duration: 15 min
• Bioavailability: < 38%
• Excretion: Urine (80-90%)
• Peak plasma time: 0.75-2 hr
• Vd: 26-61 L
• Vdss: 340 L