warnings and cautions
5 WARNINGS AND PRECAUTIONS Renal Impairment : Evaluate the risks and benefits in patients with known renal impairment or taking nephrotoxic drugs; monitor renal function ( 5.1 , 7.1 , 8.6 , 13.2 ) Mesalamine-induced Acute Intolerance Syndrome : Symptoms may be difficult to distinguish from an ulcerative colitis exacerbation; monitor for worsening symptoms; discontinue if acute intolerance syndrome suspected ( 5.2 ) Hypersensitivity Reactions , including Myocarditis and Pericarditis : Evaluate patients immediately and discontinue if a hypersensitivity reaction is suspected ( 5.3 ) Hepatic Failure : Evaluate the risks and benefits in patients with known liver impairment ( 5.4 ) Iron Content of Asacol HD : Consider the iron content of Asacol HD in patients taking iron supplementation and those at risk of iron overload. ( 5.5 ) 5.1 Renal Impairment Renal impairment, including minimal change nephropathy, acute and chronic interstitial nephritis, and, rarely, renal failure, has been reported in patients taking products such as Asacol HD that contain or are converted to mesalamine [see Adverse Reactions (6.2) ] . Evaluate renal function prior to initiation of Asacol HD and periodically while on therapy. Evaluate the risks and benefits of using Asacol HD in patients with known renal impairment or history of renal disease or taking concomitant nephrotoxic drugs [ see Drug Interactions (7.1) , Use in Specific Populations (8.6) and Nonclinical Toxicology (13.2) ] . 5. 2 Mesalamine-Induced Acute Intolerance Syndrome Mesalamine has been associated with an acute intolerance syndrome that may be difficult to distinguish from an exacerbation of ulcerative colitis. Exacerbation of the symptoms of colitis has been reported in 2.3% of Asacol HD-treated patients in controlled clinical trials. This acute reaction, characterized by cramping, abdominal pain, bloody diarrhea, and occasionally by fever, headache, malaise, pruritus, rash, and conjunctivitis, has been reported after the initiation of Asacol HD tablets as well as other mesalamine products. Symptoms usually abate when Asacol HD tablets are discontinued. 5. 3 Hypersensitivity Reactions Hypersensitivity reactions have been reported in patients taking sulfasalazine. Some patients may have a similar reaction to Asacol HD tablets or to other compounds that contain or are converted to mesalamine. As with sulfasalazine, mesalamine-induced hypersensitivity reactions may present as internal organ involvement, including myocarditis, pericarditis, nephritis, hepatitis, pneumonitis, and hematologic abnormalities. Evaluate patients immediately if signs or symptoms of a hypersensitivity reaction are present. Discontinue Asacol HD if an alternative etiology for the signs or symptoms cannot be established. 5. 4 Hepatic Failure There have been reports of hepatic failure in patients with pre-existing liver disease who have been administered mesalamine. Caution should be exercised when administering Asacol HD to patients with liver impairment. 5.5 Iron Content of Asacol HD Asacol HD contains iron oxide as a colorant in the coating of the delayed-release tablets. Each 800 mg delayed-release tablet contains 4.9 mg of iron. The total content of iron is 29.2 mg at the recommended daily dosage [see Dosage and Administration ( 2.2 )]. Before prescribing Asacol HD to patients receiving iron supplementation or those at risk for developing iron overload, consider the combined daily amount of iron from all sources, including Asacol HD.