Olsalazine

Mesalamine-induced acute intolerance syndrome may occur; drug is converted to mesalamine, which has been associated with acute intolerance syndrome that may be difficult to distinguish from exacerbation of ulcerative colitis; symptoms include cramping, acute abdominal pain and bloody diarrhea, sometimes fever, headache, and rash; monitor patients for worsening of symptoms while on treatment; discontinue therapy if acute intolerance syndrome suspected

Some patients who have experienced a hypersensitivity reaction to sulfasalazine have similar reaction to drug or to other compounds that contain or are converted to mesalamine; 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 present; discontinue therapy if an alternative etiology for signs and symptoms cannot be established

There have been reports of hepatic failure in patients with pre-existing liver disease receiving therapy; because drug is converted to mesalamine, evaluate risks and benefits of therapy in patients with known liver impairment

Patients with pre-existing skin conditions such as atopic dermatitis and atopic eczema have reported more severe photosensitivity reactions when receiving therapy; advise patients to avoid sun exposure, wear protective clothing, and use a broad-spectrum sunscreen when outdoors

Cases of nephrolithiasis have been reported with use of mesalamine; active moiety in drug, including stones with 100% mesalamine content; mesalamine-containing stones are radiotransparent and undetectable by standard radiography or computed tomography (CT); ensure adequate hydration during treatment

Severe cutaneous adverse reactions, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) reported with use, discontinue therapy at first signs or symptoms of severe cutaneous adverse reactions or other signs of hypersensitivity and consider further evaluation