Anemia, changes in the number of WBC & platelets eg, agranulocytosis, leukopenia, methemoglobinemia, neutropenia, pancytopenia, thrombocytopenia; thrombocytopenic purpura; allergic reactions which may cause difficulty swallowing, unexplained wheezing, shortness of breath or difficulty in breathing, skin rash, hives, or angioedema, proneness to infections, swelling around the eyes; hyperchloremia, hyperuricemia, loss of appetite, metabolic acidosis, sudden wt loss; headache; unusual bleeding or bruising; resp distress, runny nose, laryngeal edema; mouth ulcers, nausea, sore throat, vomiting; fixed eruption, itchy rash, severe skin reactions (ie, SJS, TEN, & acute generalized exanthematous pustulosis); chronic hepatic necrosis in prolonged use, liver dysfunction & injury, yellowing of eyes & skin; kidney toxicity, papillary necrosis in prolonged use; fatigue or unusual tiredness; decreased serum bicarbonate, Ca & Na; increases in serum alkaline phosphatase, glucose & transaminase levels.