Yes

Analgesic, Miscellaneous

Dental: Treatment of postoperative pain

Medical: Treatment of mild to moderate pain and fever; does not have antirheumatic effects (analgesic)

B

Patients with known G-6-PD deficiency; hypersensitivity to acetaminophen

May cause severe hepatic toxicity on overdose; use with caution in patients with alcoholic liver disease; chronic daily dosing in adults of 5-8 g of acetaminophen over several weeks or 3-4 g/day of acetaminophen for 1 year have resulted in liver damage

Percentage unknown: May increase chloride, bilirubin, uric acid, glucose, ammonia, alkaline phosphatase; may decrease sodium, bicarbonate, calcium

Refer to the Acetaminophen Toxicity Nomogram in the Appendix

Acetylcysteine 140 mg/kg orally (loading) followed by 70 mg/kg every 4 hours for 17 doses. Therapy should be initiated based upon laboratory analysis suggesting high probability of hepatotoxic potential. Activated charcoal is very effective at binding acetaminophen.

CYP1A2 enzyme substrate (minor), CYP2E1 and 3A3/4 enzyme substrate

Increased toxicity: Barbiturates, carbamazepine, hydantoins, sulfinpyrazone can increase the hepatotoxic potential of acetaminophen; chronic ethanol abuse increases risk for acetaminophen toxicity; effect of warfarin may be enhanced

Inhibits the synthesis of prostaglandins in the central nervous system and peripherally blocks pain impulse generation; produces antipyresis from inhibition of hypothalamic heat-regulating center

Onset: <1 hour

Duration: 4-6 hours

Protein binding: 20% to 50%

Metabolism: At normal therapeutic dosages, the parent compound is metabolized in the liver to sulfate and glucuronide metabolites, while a small amount is metabolized by microsomal mixed function oxidases to a highly reactive intermediate (acetylimidoquinone) which is conjugated with glutathione and inactivated; at toxic doses (as little as 4 g in a single day) glutathione conjugation becomes insufficient to meet the metabolic demand causing an increase in acetylimidoquinone concentration, which is thought to cause hepatic cell necrosis

Half-life:

Neonates: 2-5 hours

Adults: Normal renal function: 1-3 hours; End-stage renal disease: 1-3 hours

Time to peak serum concentration: Oral: 10-60 minutes after normal doses, may be delayed in acute overdoses

Oral, rectal (if fever not controlled with acetaminophen alone, administer with full doses of aspirin on an every 4- to 6-hour schedule, if aspirin is not otherwise contraindicated):

0-3 months: 40 mg

4-11 months: 80 mg

1-2 years: 120 mg

2-3 years: 160 mg

4-5 years: 240 mg

6-8 years: 320 mg

9-10 years: 400 mg

11 years: 480 mg

Adults: 325-650 mg every 4-6 hours or 1000 mg 3-4 times/day; do not exceed 4 g/day

Dosing interval in renal impairment:

Cl_cr 10-50 mL/minute: Administer every 6 hours

Cl_cr <10 mL/minute: Administer every 8 hours (metabolites accumulate)

Hemodialysis: Moderately dialyzable (20% to 50%)

Dosing adjustment/comments in hepatic impairment: Appears to be well tolerated in cirrhosis; serum levels may need monitoring with long-term use

Food: May slightly delay absorption of extended-release preparations; rate of absorption may be decreased when given with food high in carbohydrates

Alcohol: Excessive intake of alcohol may increase the risk of acetaminophen-induced hepatotoxicity; avoid or limit alcohol intake

Relief of pain or fever

Therapeutic concentration (analgesic/antipyretic): 10-30 mg/mL

Toxic concentration (acute ingestion) with probable hepatotoxicity: >200 mg/mL at 4 hours or 50 mg/mL at 12 hours after ingestion

None reported

Barbiturates and carbamazepine may increase the hepatotoxic potential of acetaminophen

No information available to require special precautions

No effects or complications reported

Take exactly as directed (do not increase dose or frequency); most adverse effects are related to excessive use. Take with food or milk. While using this medication, avoid alcohol and other prescription or OTC medications that contain acetaminophen. Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). This medication will not reduce inflammation; consult prescriber for anti-inflammatory, if needed. Report unusual bleeding (stool, mouth, urine) or bruising; unusual fatigue and weakness; change in elimination patterns; or change in color of urine or stool.

Suppositories: Do not freeze

Suspension, oral: Shake well before pouring a dose

Caplet: 160 mg, 325 mg, 500 mg

Caplet, extended: 650 mg

Capsule: 80 mg

Drops: 48 mg/mL (15 mL); 60 mg/0.6 mL (15 mL); 80 mg/0.8 mL (15 mL); 100 mg/mL (15 mL, 30 mL)

Elixir: 80 mg/5 mL, 120 mg/5 mL, 160 mg/5 mL, 167 mg/5 mL, 325 mg/5 mL

Liquid, oral: 160 mg/5 mL, 500 mg/15 mL

Solution: 100 mg/mL (15 mL); 120 mg/2.5 mL

Suppository, rectal: 80 mg, 120 mg, 125 mg, 300 mg, 325 mg, 650 mg

Suspension, oral: 160 mg/5 mL

Suspension, oral drops: 80 mg/0.8 mL

Tablet: 325 mg, 500 mg, 650 mg

Tablet, chewable: 80 mg, 160 mg

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