The frequency of this or that side effect is determined by the following table:
| Frequency | The appearance of side effects |
| often: | in 1-10 patients out of 100 |
| infrequently: | less than 1 patient out of 100 |
| rarely: | less than 1 patient out of 1,000 |
| rarely: | less than 1 patient out of 10 000 |
| in some cases: | less than 1 patient out of more than 10 000 |
From the digestive system
Often: nausea, diarrhea, increased activity of liver enzymes (eg, alanine aminotransferase and aspartate aminotransferase).
Infrequently: decreased appetite, vomiting, abdominal pain, digestive disorders.
Rarely: Diarrhea (including blood), which in very rare cases can be a sign of inflammation of the intestine and even pseudomembranous colitis (see section "Special instructions"), increased serum bilirubin concentration, dysbacteriosis.
Rarely: increased serum creatinine concentration, impaired liver function, acute renal failure, hepatitis.
From the nervous system
Infrequently: headache, dizziness, drowsiness, insomnia.
Rarely: depression, anxiety, psychotic reactions (for example, with hallucinations), unpleasant sensations (for example, paresthesia in the hands), tremor, weakness, excited state, motor disorders, convulsions and confusion, suicidal thoughts.
Rarely: impaired vision and hearing, impaired taste sensitivity and smell, decreased tactile sensitivity, peripheral sensory neuropathy, peripheral sensory-motor neuropathy, dyskinesia, extrapyramidal frustration, fear, agitation, mental disorders with behavioral disorders with self-harm, suicide attempts.
From the side of cardiovascular systems
Rarely: tachycardia, decrease blood pressure.
Rarely: cardiovascular collapse.
In some cases: lengthening interval QT, atrial fibrillation.
From the side of metabolism
Rarely: decrease in concentration glucose in the blood (hypoglycemia), which is of particular importance for diabetics, with symptoms: increased appetite, nervousness, sweating, trembling.
From the side of the locomotor system apparatus
Rarely: affections of tendons (including tendonitis), arthralgia, myalgia.
Rarely: rupture of tendons (for example, Achilles tendon), muscle weakness.
In some cases: muscle damage (rhabdomyolysis).
From the urinary system
Rarely: hypercreatininaemia, interstitial nephritis, renal dysfunction, acute renal failure.
On the part of the organs of hematopoiesis
Infrequently: eosinophilia, leukopenia.
Rarely: neutropenia; thrombocytopenia, hemorrhage.
Rarely: agranulocytosis.
In some cases: hemolytic anemia, pancytopenia.
Allergic reactions
Infrequently: itching and redness of the skin.
Rarely: are common reactions hypersensitivity (anaphylactic and anaphylactoid reactions) with symptoms such as urticaria, bronchospasm and laryngospasm, severe suffocation.
In very rare cases: swelling of the skin and mucous membrane (for example, in the face and pharynx), anaphylactic shock, allergic pneumonitis, vasculitis.
In some cases: severe skin rashes with the formation of blisters, for example, Stevens-Johnson syndrome, toxic epidermal necrolysis (Lyell's syndrome), and exudative erythema multiforme.
Other
Infrequently: general weakness (asthenia).
Rarely: "tinnitus".
Rarely: exacerbation of porphyria, fever, photosensitivity, development of superinfection, dyspnea; the development of severe infections (persistent or recurrent fever, sore throat and persistent worsening of health).