Acetaminophen Interactions

Brand names: Acetaminophen

Route: Intravenous

FDA Black Box Warning

WARNING: RISK OF MEDICATION ERRORS AND HEPATOTOXICITY Take care when prescribing, preparing, and administering acetaminophen injection 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. Acetaminophen injection contains acetaminophen. Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed the maximum daily limits, and often involve more than one acetaminophen-containing product [see Warnings and Precautions (5.1) ]. WARNING: RISK OF MEDICATION ERRORS AND HEPATOTOXICITY See full prescribing information for complete boxed warning Take care when prescribing, preparing, and administering acetaminophen injection to avoid dosing errors which could result in accidental overdose and death. Acetaminophen injection contains acetaminophen. Acetaminophen has been associated with cases of acute liver failure, at times resulting in liver transplant and death. Most of the cases of liver injury are associated with the use of acetaminophen at doses that exceed the recommended maximum daily limits, and often involve more than one acetaminophen-containing product. ( 5.1 )

Contraindications

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 )

Pregnancy & Breastfeeding

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%)

55 interactions on record

Acetaminophen + DapsoneMajor

Induces methemoglobinemia; concomitant use may increase risk for developing methemoglobinemia.

Source: NLP:dapsone

Acetaminophen + IsoniazidMajor

Isoniazid induces P-450IIE1 enzyme, increasing conversion of acetaminophen to toxic metabolites and potentiating hepatotoxicity. Severe acetaminophen toxicity has been reported.

Source: NLP:isoniazid

Acetaminophen + LidocaineMajor

Increased risk of methemoglobinemia when used concurrently with lidocaine.

Source: NLP:lidocaine

Acetaminophen + Lidothol PatchMajor

Increased risk of methemoglobinemia when local anesthetics are concurrently exposed to oxidizing agents.

Source: NLP:lidothol patch

Acetaminophen + MetyraponeMajor

Metyrapone inhibits glucuronidation of acetaminophen, decreasing elimination and increasing risk of adverse reactions. Avoid concomitant use.

Source: NLP:metyrapone

Acetaminophen + Triamcinolone AcetonideMajor

Increased risk of methemoglobinemia when concurrently exposed.

Source: NLP:bupivacaine hydrochloride, lidocaine hydrochloride, triamcinolone acetonide, povidine iodine

Acetaminophen + AlcoholModerate

Ethanol has complex effects on acetaminophen metabolism; excessive alcohol can induce hepatic cytochromes increasing hepatotoxic potential, while also acting as competitive inhibitor of acetaminophen metabolism.

Source: NLP:acetaminophen

Acetaminophen + BupivacaineModerate

May increase risk of methemoglobinemia when concurrently exposed with bupivacaine.

Source: NLP:bupivacaine

Acetaminophen + BusulfanModerate

Use within 72 hours prior to or concurrent with busulfan may result in reduced busulfan clearance by decreasing glutathione levels.

Source: NLP:busulfan

Acetaminophen + DiflunisalModerate

Concomitant administration resulted in approximately 50% increase in plasma levels of acetaminophen. Should be used cautiously with careful monitoring due to hepatotoxicity risk of acetaminophen at high doses.

Source: NLP:diflunisal

Acetaminophen + ExenatideModerate

Exenatide slows gastric emptying, potentially reducing the rate of absorption of orally administered drugs like acetaminophen. Use caution with oral medications.

Source: NLP:exenatide

Acetaminophen + MetoclopramideModerate

Metoclopramide may increase the rate and/or extent of absorption of acetaminophen from the small bowel.

Source: NLP:metoclopramide

Acetaminophen + NicotineModerate

Smoking cessation with nicotine replacement may require dose decrease due to deinduction of hepatic enzymes.

Source: NLP:nicotine

Acetaminophen + ProbenecidModerate

Probenecid increases plasma elimination half-life and concentrations of acetaminophen; lower dosage may be required.

Source: NLP:probenecid

Acetaminophen + Probenecid And ColchicineModerate

Probenecid increases mean plasma elimination half-life and plasma concentrations of acetaminophen; use lower dosages cautiously.

Source: NLP:probenecid and colchicine

Acetaminophen + Warfarin SodiumModerate

Chronic oral acetaminophen use at 4000 mg/day increases INR in some patients stabilized on warfarin. More frequent INR assessment may be appropriate during concurrent use.

Source: NLP:acetaminophen

Acetaminophen + ArgatrobanMinor

No drug-drug interactions have been demonstrated between argatroban and acetaminophen.

Source: NLP:argatroban

Acetaminophen + FinasterideMinor

Used concomitantly in clinical studies without evidence of clinically significant adverse interactions.

Source: NLP:finasteride

Acetaminophen + TerazosinMinor

Terazosin has been used concomitantly with acetaminophen in at least 50 patients with no interactions observed.

Source: NLP:terazosin