Acetaminophen

1 INDICATIONS AND USAGE Acetaminophen injection is indicated for the management of mild to moderate pain in adult and pediatric patients 2 years and older the management of moderate to severe pain with adjunctive opioid analgesics in adult and pediatric patients 2 years and older the reduction of fever in adult and pediatric patients. Acetaminophen injection is indicated for the Management of mild to moderate pain in adult and pediatric patients 2 years and older ( 1 ) Management of moderate to severe pain with adjunctive opioid analgesics in adult and pediatric patients 2 years and older ( 1 ) Reduction of fever in adult and pediatric patients ( 1 )

2 DOSAGE AND ADMINISTRATION Acetaminophen injection may be given as a single or repeated dose. ( 2.1 ) Acetaminophen injection should be administered only as a 15-minute intravenous infusion. ( 2.4 ) Adults and Adolescents Weighing 50 kg and Over: 1000 mg every 6 hours or 650 mg every 4 hours to a maximum of 4000 mg per day. Minimum dosing interval of 4 hours. ( 2.2 ) Adults and Adolescents Weighing Under 50 kg: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours to a maximum of 75 mg/kg per day. Minimum dosing interval of 4 hours. ( 2.2 ) Children: Children 2 to 12 years of age: 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours to a maximum of 75 mg/kg per day. Minimum dosing interval of 4 hours. ( 2.3 ) Neonates and Infants: Neonates including premature neonates born at ≥ 32 weeks gestational age to 28 days chronological age, 12.5 mg/kg every 6 hours to a maximum of 50 mg/kg per day. Minimum dosing interval of 6 hours. ( 2.4 ) Infants (29 days to 2 years of age): 15 mg/kg every 6 hours to a maximum of 60 mg/kg per day. Minimum dosing interval of 6 hours. ( 2.4 ) 2.1 General Dosing Information Acetaminophen injection may be given as a single or repeated dose for the treatment of acute pain or fever. No dose adjustment is required when converting between oral acetaminophen and acetaminophen injection dosing in adults and adolescents who weigh 50 kg and above. Calculated maximum daily dose of acetaminophen is based on all routes of administration (i.e., intravenous, oral, and rectal) and all products containing acetaminophen. Exceeding the maximum mg/kg daily dose of acetaminophen as described in Tables 1 to 3 may result in hepatic injury, including the risk of liver failure and death. To avoid the risk of overdose, ensure that the total amount of acetaminophen from all routes and from all sources does not exceed the maximum recommended dose. 2.2 Recommended Dosage: Adults and Adolescents Adults and adolescents weighing 50 kg and over: the recommended dosage of acetaminophen injection is 1000 mg every 6 hours or 650 mg every 4 hours, with a maximum single dose of acetaminophen injection of 1000 mg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 4000 mg per day (includes all routes of administration and all acetaminophen-containing products including combination products). Adults and adolescents weighing under 50 kg: the recommended dosage of acetaminophen injection is 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours, with a maximum single dose of acetaminophen injection of 15 mg/kg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 75 mg/kg per day (includes all routes of administration and all acetaminophen-containing products including combination products). Table 1. Dosing for Adults and Adolescents Age group Dose given every 4 hours Dose given every 6 hours Maximum single dose Maximum total daily dose of acetaminophen (by all routes) Adults and adolescents (13 years and older) weighing ≥ 50 kg 650 mg 1000 mg 1000 mg 4000 mg in 24 hours Adults and adolescents (13 years and older) weighing < 50 kg 12.5 mg/kg 15 mg/kg 15 mg/kg (up to 750 mg) 75 mg/kg in 24 hours (up to 3750 mg) 2.3 Recommended Dosage: Children Children 2 to 12 years of age: the recommended dosage of acetaminophen injection is 15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours, with a maximum single dose of acetaminophen injection of 15 mg/kg, a minimum dosing interval of 4 hours, and a maximum daily dose of acetaminophen of 75 mg/kg per day. Table 2. Dosing for Children Age group Dose given every 4 hours Dose given every 6 hours Maximum single dose Maximum total daily dose of acetaminophen (by all routes) Children 2 to 12 years of age 12.5 mg/kg 15 mg/kg 15 mg/kg (up to 750 mg) 75 mg/kg in 24 hours (up to 3750 mg) 2.4 Recommended Dosage For Treatment of Fever in Neonates and Infants Neonates, including premature neonates born at ≥ 32 weeks gestational age, up to 28 days chronological age: t…

5 WARNINGS AND PRECAUTIONS Administration of acetaminophen in doses higher than recommended (by all routes of administration and from all acetaminophen-containing products including combination products) may result in hepatic injury, including the risk of liver failure and death. ( 5.1 ) Use caution when administering acetaminophen in patients with the following conditions: hepatic impairment or active hepatic disease, in cases of alcoholism, chronic malnutrition, severe hypovolemia, or severe renal impairment (creatinine clearance ≤ 30 mL/min). ( 5.1 ) Discontinue acetaminophen injection immediately at the first appearance of skin rash and if symptoms associated with allergy or hypersensitivity occur. Do not use in patients with acetaminophen allergy. ( 5.2 , 5.4 ) Take care when prescribing, preparing, and administering acetaminophen injection to avoid dosing errors which could result in accidental overdose and death. ( 5.3 ) 5.1 Hepatic Injury Administration of acetaminophen in doses higher than recommended may result in hepatic injury, including the risk of liver failure and death [see Overdosage (10) ] . Do not exceed the maximum recommended daily dose of acetaminophen [see Dosage and Administration (2) ] . The maximum recommended daily dose of acetaminophen includes all routes of acetaminophen administration and all acetaminophen-containing products administered, including combination products. Use caution when administering acetaminophen in patients with the following conditions: hepatic impairment or active hepatic disease, alcoholism, chronic malnutrition, severe hypovolemia (e.g., due to dehydration or blood loss), or severe renal impairment (creatinine clearance ≤ 30 mL/min) [see Use in Specific Populations ( 8.6 , 8.7) ] . 5.2 Serious Skin Reactions Rarely, acetaminophen may cause serious skin reactions such as acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), and toxic epidermal necrolysis (TEN), which can be fatal. Patients should be informed about the signs of serious skin reactions, and use of the drug should be discontinued at the first appearance of skin rash or any other sign of hypersensitivity. 5.3 Risk of Medication Errors Take care when prescribing, preparing, and administering acetaminophen in order to avoid dosing errors which could result in accidental overdose and death. In particular, be careful to ensure that: the dose in milligrams (mg) and milliliters (mL) is not confused; the dosing is based on weight for patients under 50 kg; infusion pumps are properly programmed; and the total daily dose of acetaminophen from all sources does not exceed maximum daily limits [see Dosage and Administration (2) ] . 5.4 Allergy and Hypersensitivity There have been post-marketing reports of hypersensitivity and anaphylaxis associated with the use of acetaminophen. Clinical signs included swelling of the face, mouth, and throat, respiratory distress, urticaria, rash, and pruritus. There were infrequent reports of life-threatening anaphylaxis requiring emergent medical attention. Discontinue acetaminophen immediately if symptoms associated with allergy or hypersensitivity occur. Do not use acetaminophen in patients with acetaminophen allergy.

4 CONTRAINDICATIONS Acetaminophen is contraindicated: in patients with known hypersensitivity to acetaminophen or to any of the excipients in the intravenous formulation. in patients with severe hepatic impairment or severe active liver disease [see Warnings and Precautions (5.1) ] . Acetaminophen is contraindicated: In patients with known hypersensitivity to acetaminophen or to any of the excipients in the IV formulation. (4) In patients with severe hepatic impairment or severe active liver disease. (4)

7 DRUG INTERACTIONS Substances that induce or regulate hepatic cytochrome enzyme CYP2E1 may alter the metabolism of acetaminophen and increase its hepatotoxic potential. ( 7.1 ) Chronic oral acetaminophen use at a dose of 4000 mg/day has been shown to cause an increase in international normalized ratio (INR) in some patients who have been stabilized on sodium warfarin as an anticoagulant. ( 7.2 ) 7.1 Effects of Other Substances on Acetaminophen Substances that induce or regulate hepatic cytochrome enzyme CYP2E1 may alter the metabolism of acetaminophen and increase its hepatotoxic potential. The clinical consequences of these effects have not been established. Effects of ethanol are complex, because excessive alcohol usage can induce hepatic cytochromes, but ethanol also acts as a competitive inhibitor of the metabolism of acetaminophen. 7.2 Anticoagulants Chronic oral acetaminophen use at a dose of 4000 mg/day has been shown to cause an increase in international normalized ratio (INR) in some patients who have been stabilized on sodium warfarin as an anticoagulant. As no studies have been performed evaluating the short-term use of acetaminophen in patients on oral anticoagulants, more frequent assessment of INR may be appropriate in such circumstances.

8.1 Pregnancy Risk Summary Published epidemiological studies with oral acetaminophen use during pregnancy have not reported a clear association with acetaminophen use and birth defects, miscarriage, or adverse maternal or fetal outcomes [see Data] . Animal reproduction studies have not been conducted with IV acetaminophen. Reproductive and developmental studies in rats and mice from the published literature identified adverse events at clinically relevant doses with acetaminophen. Treatment of pregnant rats with doses of acetaminophen approximately equal to the maximum human daily dose (MHDD) showed evidence of fetotoxicity and increases in bone variations in the fetuses. In another study, necrosis was observed in the liver and kidney of both pregnant rats and fetuses at doses approximately equal to the MHDD. In mice and rats treated with acetaminophen at doses within the clinical dosing range, cumulative adverse effects on reproductive capacity were reported. In mice, a reduction in number of litters of the parental mating pair was observed as well as retarded growth, abnormal sperm in their offspring and reduced birth weight in the next generation. In rats, female fertility was decreased following in utero exposure to acetaminophen [see Data]. The estimated background risk of major birth defects and miscarriages for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively. Data Human Data The results from a large population-based prospective cohort, including data from 26,424 women with live born singletons who were exposed to oral acetaminophen during the first trimester, indicate no increased risk for congenital malformations, compared to a control group of unexposed children. The rate of congenital malformations (4.3%) was similar to the rate in the general population. A population-based, case-control study from the National Birth Defects Prevention Study showed that 11,610 children with prenatal exposure to acetaminophen during the first trimester had no increased risk of major birth defects compared to 4,500 children in the control group. Other epidemiological data showed similar results. However, these studies cannot definitely establish the absence of any risk because of methodological limitations, including recall bias. Animal Data Studies in pregnant rats that received oral acetaminophen during organogenesis at doses up to 0.85 times the maximum human daily dose (MHDD = 4 grams/day, based on a body surface area comparison) showed evidence of fetotoxicity (reduced fetal weight and length) and a dose-related increase in bone variations (reduced ossification and rudimentary rib changes). Offspring had no evidence of external, visceral, or skeletal malformations. When pregnant rats received oral acetaminophen throughout gestation at doses of 1.2 times the MHDD (based on a body surface area comparison), areas of necrosis occurred in both the liver and kidney of pregnant rats and fetuses. These effects did not occur in animals that received oral acetaminophen at doses 0.3 times the MHDD, based on a body surface area comparison. In a continuous breeding study, pregnant mice received 0.25, 0.5, or 1.0% acetaminophen via the diet (357, 715, or 1430 mg/kg/day). These doses are approximately 0.43, 0.87, and 1.7 times the MHDD, respectively, based on a body surface area comparison. A dose related reduction in body weights of fourth and fifth litter offspring of the treated mating pair occurred during lactation and post-weaning at all doses. Animals in the high dose group had a reduced number of litters per mating pair, male offspring with an increased percentage of abnormal sperm, and reduced birth weights in the next generation pups.

8.3 Females and Males of Reproductive Potential Based on animal data use of acetaminophen may cause reduced fertility in males and females of reproductive potential. It is not known whether these effects on fertility are reversible. Published animal studies reported that oral acetaminophen treatment of male animals at doses that are 1.2 times the MHDD and greater (based on a body surface area comparison) result in decreased testicular weights, reduced spermatogenesis, and reduced fertility. In female animals given the same doses, reduced implantation sites were reported. Additional published animal studies indicate that acetaminophen exposure in utero adversely impacts reproductive capacity of both male and female offspring at clinically relevant exposures [see Nonclinical Toxicology (13.1) ] .

6 ADVERSE REACTIONS The following serious adverse reactions are discussed elsewhere in the labeling: Hepatic Injury [see Warnings and Precautions (5.1) ] Serious Skin Reactions [see Warnings and Precautions (5.2 )] Allergy and Hypersensitivity [see Warnings and Precautions (5.4) ] The most common adverse reactions in patients treated with acetaminophen injection were nausea, vomiting, headache, and insomnia in adult patients; nausea, vomiting, constipation, and pruritus in pediatric patients. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Aspiro Pharma Limited at 1-866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed cannot be directly compared to rates in other clinical trials and may not reflect the rates observed in practice. Adult Population A total of 1020 adult patients have received acetaminophen in clinical trials, including 37.3% (n=380) who received 5 or more doses, and 17.0% (n=173) who received more than 10 doses. Most patients were treated with acetaminophen 1000 mg every 6 hours. A total of 13.1% (n=134) received acetaminophen 650 mg every 4 hours. All adverse reactions that occurred in adult patients treated with either acetaminophen or placebo in repeated dose, placebo-controlled clinical trials at an incidence ≥ 3% and at a greater frequency than placebo are listed in Table 4. The most common adverse events in adult patients treated with acetaminophen (incidence ≥ 5% and greater than placebo) were nausea, vomiting, headache, and insomnia. Table 4. Treatment-Emergent Adverse Reactions Occurring in ≥ 3% of Acetaminophen-treated Adult Patients and at a Greater Frequency than Placebo in Placebo-Controlled, Repeated Dose Studies System Organ Class–Preferred Term Acetaminophen (N=402) n (%) Placebo (N=379) n (%) Gastrointestinal Disorders Nausea Vomiting 138 (34) 62 (15) 119 (31) 42 (11) General Disorders and Administration Site Conditions Pyrexia* 22 (5) 52 (14) Nervous System Disorders Headache 39 (10) 33 (9) Psychiatric Disorders Insomnia 30 (7) 21 (5) * Pyrexia adverse reaction frequency data is included in order to alert healthcare practitioners that the antipyretic effects of acetaminophen may mask fever. Other Adverse Reactions Observed During Clinical Studies of Acetaminophen in Adults The following additional treatment-emergent adverse reactions were reported by adult subjects treated with acetaminophen in all clinical trials (n=1020) that occurred with an incidence of at least 1% and at a frequency greater than placebo (n=525). Blood and lymphatic system disorders: anemia General disorders and administration site conditions: fatigue, infusion site pain, edema peripheral Investigations: aspartate aminotransferase increased, breath sounds abnormal Metabolism and nutrition disorders: hypokalemia Musculoskeletal and connective tissue disorders: muscle spasms, trismus Psychiatric disorders: anxiety Respiratory, thoracic and mediastinal disorders: dyspnea Vascular disorders: hypertension, hypotension Pediatric Population A total of 483 pediatric patients (72 neonates, 167 infants, 171 children, and 73 adolescents) have received acetaminophen in active-controlled (n=250) and open-label clinical trials (n=225), including 43.9% (n=212) who received 5 or more doses and 31.2% (n=153) who received more than 10 doses. Pediatric patients received acetaminophen doses up to 15 mg/kg on an every 4 hours, every 6 hours, or every 8 hours schedule. The maximum exposure was 7.7, 6.4, 6.8, and 7.1 days in neonates, infants, children, and adolescents, respectively. The most common adverse events (incidence ≥ 5%) in pediatric patients treated with acetaminophen were nausea, vomiting, constipation, and pruritus. Other Adverse Reactions Observed During Clinical Studies of Acetaminophen in Pediatrics The following additional treatment-emergent adverse reactions were reported by pediat…