According to the World Health Organization (WHO), adverse reactions are classified according to their frequency of development as follows: very often (> 1/10), often (>1/100, <1/10), infrequently (>1/1000, <1/100), rarely (>1/10000, <1/1000) and very rarely (<1/10000); frequency seemed possible.
From the gastrointestinal side tract:
often: nausea, vomiting, diarrhea, dyspepsia, abdominal pain, flatulence, anorexia;
rarely: gastritis, vomiting with an admixture of blood, gastrointestinal
bleeding, melena, gastric or intestinal ulcers, possibly with complications (bleeding, perforation), frequent stools with a trace of blood, proctitis;
rarely: stomatitis, glossitis, esophagitis, esophageal motility disorder, pancreatitis, intestinal stricture, nonspecific
hemorrhagic colitis, exacerbation of ulcerative colitis or Crohn's disease, constipation, exacerbation of hemorrhoids.
From the nervous system:
often: headache, dizziness;
rarely: drowsiness;
rarely: depression, irritability, aseptic meningitis (usually in patients with systemic lupus erythematosus and other systemic connective tissue diseases), weakness,disorientation, nightmarish dreams, a sense of fear, memory impairment, tremor, cerebrovascular disorders, impaired sensitivity (including paresthesia), seizures.
From the senses: often: vertigo, coordination disorder;
rarely: noise in the ears, hearing impairment, blurred vision, diplopia, a violation of taste sensations.
From the urinary system:
rarely: acute renal failure, hematuria, proteinuria, nephrotic syndrome, interstitial nephritis, papillary necrosis.
From the organs of hematopoiesis and the immune system:
rarely: anaphylactic reactions (including lowering blood pressure and anaphylactic shock);
rarely: anemia (including hemolytic and aplastic anemia), leukopenia, thrombocytopenia, eosinophilia, agranulocytosis, thrombocytopenic purpura, worsening of the course of infectious processes (development of necrotizing fasciitis, pneumonia), angioedema (including Quincke's edema).
From the respiratory system:
rarely: cough, bronchospasm, laryngeal edema;
rarely: pneumonitis.
From the cardiovascular system:
infrequently: myocardial infarction, chronic heart failure, palpitations and chest pain;
rarely: increased blood pressure, vasculitis, extrasystole.
From the skin:
often: skin itching, skin rash; rarely: hives; rarely: erythema, bullous rashes, chronic dermatitis, eczema, polymorphic erythema, toxic epidermal necrolysis (Lyell's syndrome, Stevens-Johnson syndrome), photosensitivity, purpura, Henoch-Schönlein purpura, exfoliative dermatitis, alopecia, photosensitivity.
From the hepatobiliary system:
often: increased activity of "liver" transaminases;
rarely: hepatitis, jaundice, dysfunction of the liver;
rarely: hepatitis (fulminant possible), hepatic necrosis, cirrhosis, hepatorenal syndrome, hepatic failure.
Other:
rarely: edema.