Acetaminophen (Page 2 of 6)

2.6 Instructions for Intravenous Administration of Doses Not Equivalent to 500 mg or 1,000 mg

Doses that are not equivalent to 500 mg or 1,000 mg require aseptic transfer to a separate container prior to dispensing. Discard unused portion. Using aseptic technique, withdraw the appropriate dose (650 mg or weight-based) from an intact sealed PAB container and place the measured dose in a separate empty, sterile container (e.g., glass bottle, plastic intravenous container, or syringe) for intravenous infusion to avoid the inadvertent delivery and administration of the total volume of the commercially available container. The entire 100 mL container is not intended for use in patients weighing less than 50 kg. Acetaminophen injection is supplied in a single-dose container and the unused portion must be discarded.

Place small volume pediatric doses up to 60 mL in volume in a syringe and administer over 15 minutes using a syringe pump.

3 DOSAGE FORMS AND STRENGTHS

Acetaminophen Injection is a sterile, clear, colorless, non-pyrogenic, preservative free, isotonic formulation of acetaminophen available as:

• 1,000 mg acetaminophen in 100 mL (10 mg/mL) injection for intravenous infusion

• 500 mg acetaminophen in 50 mL (10 mg/mL) injection for intravenous infusion

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)].

5 WARNINGS AND PRECAUTIONS

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 less than or equal to 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 Injection 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 Injection immediately if symptoms associated with allergy or hypersensitivity occur. Do not use Acetaminophen Injection in patients with acetaminophen allergy.

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) ]

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 1,020 adult patients have received Acetaminophen Injection 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 Injection 1,000 mg every 6 hours. A total of 13.1% (n=134) received Acetaminophen Injection 650 mg every 4 hours.

All adverse reactions that occurred in adult patients treated with either Acetaminophen Injection or placebo in repeated dose, placebo-controlled clinical trials at an incidence greater than or equal to 3% and at a greater frequency than placebo are listed in Table 4. The most common adverse events in adult patients treated with Acetaminophen Injection (incidence greater than or equal to 5% and greater than placebo) were nausea, vomiting, headache, and insomnia.

Table 4. Treatment-Emergent Adverse Reactions Occurring in greater than or equal to 3% of Acetaminophen Injection-treated Adult Patients and at a Greater Frequency than Placebo in Placebo-Controlled, Repeated Dose Studies

* Pyrexia adverse reaction frequency data is included in order to alert healthcare practitioners that the antipyretic effects of Acetaminophen Injection may mask fever.
System Organ Class – Preferred Term	Acetaminophen Injection (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)

Other Adverse Reactions Observed During Clinical Studies of Acetaminophen Injection in Adults

The following additional treatment-emergent adverse reactions were reported by adult subjects treated with Acetaminophen Injection in all clinical trials (n=1,020) 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