From the digestive system: decreased or loss of appetite, increased salivation, nausea, vomiting, flatulence, abdominal pain, diarrhea or constipation, heartburn; increased activity of "hepatic" transaminases, hyperbilirubinemia, jaundice; drug-induced hepatitis (including fatal), hepatomegaly, partially pronounced malabsorption syndrome, bleeding peptic ulcers.
From the hematopoiesis: thrombocytopenia, neutropenia, lengthening prothrombin time, accompanied by bleeding and hemorrhagic purpura, lymphocytosis, leukopenia (up to agranulocytosis), B 12-deficient megaloblastic anemia, hemolytic anemia with a positive Coombs breakdown.
From the genitourinary system: proteinuria, hematuria, crystalluria, glucosuria, an increase in urea concentration in the blood plasma.
Allergic reactions: rash (hives, purpura, enanthema, exfoliative dermatitis, a syndrome reminiscent of infectious mononucleosis or lymphoma), Quincke's edema, fever, bronchospasm, arthralgia, eosinophilia, Stevens-Johnson syndrome, Lyell's syndrome. anaphylactic shock, itching, erythema.
Other: fever, arthralgia, sore throat, unusual bleeding and bruising, swelling of the joints, lupus-like syndrome, accompanied by lesions of the spleen, liver, kidneys, digestive tract, bone marrow and nervous system (eg, radicular pain, meningism); with prolonged use in high doses - Hypothyroidism, goiter (with or without myxedema); pericarditis, hypoglycemia, hyperglycemia, hypokalemia, optic neuritis, encephalopathy, psychosis, seizures,symptoms of paralysis, Leffler's syndrome (eosinophilic pneumonia, migratory pulmonary infiltrate), vasculitis, a decrease in prothrombin content, superinfection.