Acetaminophen: Substrate (minor) of CYP1A2, 2A6, 2C8/9, 2D6, 2E1, 3A4; Inhibits CYP3A4 (weak)

Chlorpheniramine: Substrate of CYP2D6 (minor), 3A4 (major); Inhibits CYP2D6 (weak)

Also see individual agents.

Analgesic: Based on acetaminophen component:

Children: 10-15 mg/kg/dose every 4-6 hours as needed; do not exceed 5 doses in 24 hours

Adults: 325-650 mg every 4-6 hours as needed; do not exceed 4 g/day

Antihistamine: Based on chlorpheniramine maleate component:

Children:

2-6 years: 1 mg every 4-6 hours (maximum: 6 mg/24 hours)

6-12 years: 2 mg every 4-6 hours (maximum: 12 mg/24 hours)

Children >12 years and Adults: 4 mg every 4-6 hours (maximum: 24 mg/24 hours)

Decongestant: Based on pseudoephedrine component:

Children:

2-6 years: 15 mg every 4 hours (maximum: 90 mg/24 hours)

6-12 years: 30 mg every 4 hours (maximum: 180 mg/24 hours)

Children >12 years and Adults: 60 mg every 4 hours (maximum: 360 mg/24 hours)

Product labeling:

Alka-Seltzer Plus Cold Medicine Liqui-Gels:

Children 6-12 years: 1 softgel every 4 hours with water (maximum: 4 doses/24 hours)

Children >12 years and Adults: 2 softgels every 4 hours with water (maximum: 4 doses/24 hours)

Sinutab Sinus Allergy Maximum Strength: Children >12 years and Adults: 2 tablets/caplets every 6 hours (maximum: 8 doses/24 hours)

Thera-Flu Cold and Sore Throat Night Time: Children >12 years and Adults: 1 packet dissolved in hot water every 6 hours (maximum: 4 packets/24 hours)

Children's Tylenol Plus Cold contains phenylalanine 6 mg/tablet.

Thera-Flu Cold and Sore Throat Night Time contains phenylalanine 11 mg/packet.

Chlorpheniramine: Significant xerostomia with prolonged use (normal salivary flow resumes upon discontinuation).

Pseudoephedrine: Xerostomia (normal salivary flow resumes upon discontinuation).

Caplet (Actifed Cold and Sinus, Comtrex Maximum Strength Sinus and Nasal Decongestant, Sinutab Sinus Allergy Maximum Strength, Tylenol Allergy Sinus): Acetaminophen 500 mg, chlorpheniramine maleate 2 mg, and pseudoephedrine hydrochloride 30 mg

Capsule, softgel (Alka-Seltzer Plus Cold Liqui-Gels): Acetaminophen 325 mg, chlorpheniramine maleate 2 mg, and pseudoephedrine hydrochloride 30 mg

Gelcap (Tylenol Allergy Sinus): Acetaminophen 500 mg, chlorpheniramine maleate 2 mg, and pseudoephedrine hydrochloride 30 mg

Geltab (Tylenol Allergy Sinus): Acetaminophen 500 mg, chlorpheniramine maleate 2 mg, and pseudoephedrine hydrochloride 30 mg

Powder for oral solution [packet] (Thera-Flu Cold and Sore Throat Night Time): Acetaminophen 650 mg, chlorpheniramine maleate 4 mg, and pseudoephedrine hydrochloride 60 mg [contains phenylalanine 11 mg/packet; lemon flavor]

Suspension (Children's Tylenol Plus Cold): Acetaminophen 160 mg, chlorpheniramine maleate 1 mg, and pseudoephedrine hydrochloride 15 mg per 5 mL (120 mL) [contains sodium benzoate; grape flavor]

Tablet, chewable (Children's Tylenol Plus Cold): Acetaminophen 80 mg, chlorpheniramine maleate 0.5 mg, and pseudoephedrine hydrochloride 7.5 mg [contains phenylalanine 6 mg/tablet; grape flavor]

Barker JD Jr, de Carle DJ, and Anuras S, "Chronic Excessive Acetaminophen Use in Liver Damage,"Ann Intern Med, 1977, 87(3):299-301.

Dionne RA, Campbell RA, Cooper SA, et al, "Suppression of Postoperative Pain by Preoperative Administration of Ibuprofen in Comparison to Placebo, Acetaminophen, and Acetaminophen Plus Codeine,"J Clin Pharmacol, 1983, 23(1):37-43.

Licht H, Seeff LB, and Zimmerman HJ, "Apparent Potentiation of Acetaminophen Hepatotoxicity by Alcohol,"Ann Intern Med, 1980, 92(4):511.

Mokhlesi B, Leikin JB, Murray P, et al, "Adult Toxicology in Critical Care: Part II: Specific Poisonings,"Chest, 2003, 123(3):897-922.