According to the World Health Organization (WHO), undesirable effects are classified according to their frequency of development as follows: very often (>1/10), often (from >1/100 to <1/10), infrequently (from >1 / 1,000 to <1/100), rarely (from >1 / 10,000 to <1 / 1,000), very rarely (<1 / 10,000); frequency is unknown - according to available data, it was not possible to establish the frequency of occurrence.
Allergic reactions:
rarely: itching of the skin, hives, rashes, including bullous, angioedema, bronchospasm, wheezing, anaphylaxis.
From the side of the cardiovascular system:
infrequently: tachycardia, orthostatic hypotension, palpitations,
cardiovascular failure, collapse;
rarely: fainting, bradycardia, increased blood pressure.
From the digestive system:
Often: nausea;
often: dryness of the oral mucosa, vomiting, constipation;
infrequently: a urge to vomit, diarrhea, irritation of the gastrointestinal tract, a feeling of heaviness in the stomach, bloating, dyspepsia;
rarely: abdominal pain, difficulty in swallowing.
From the central nervous system:
Often: dizziness; often: headache, drowsiness;
rarely: weakness, increased fatigue, paradoxical stimulation central nervous system (nervousness, agitation, anxiety, tremor, muscle spasms, euphoria, dysphoria, emotional lability, hallucinations), sleep disorders, sweating, confusion, disorders of coordination of motion, convulsions of central genesis (with intravenously in high doses or with simultaneous use of drugs that reduce the threshold convulsive
preparedness), depression, amnesia, cognitive impairment and sensory perception (for example, the ability to make a decision, to realize problems), paresthesia, unsteadiness of gait, blurred vision, a violation of appetite, "nightmarish" dreams;
frequency is unknown: speech disorders.
From the skin:
often: increased sweating;
infrequently: urticaria, rash, including bullous, itching.
From the side of the musculoskeletal system:
rarely: muscle weakness.
From the urinary system:
rarely: different types of dysuria.
Laboratory indicators:
rarely: increased activity of "liver" transaminases.
From the sense organs:
rarely: impaired vision, taste;
frequency is unknown: mydriasis.
From the respiratory system:
rarely: respiratory depression, dyspnea.
Other:
often: fatigue,
rarely: violation of the menstrual cycle.
Symptoms of the withdrawal reaction, similar to the response of opiate withdrawal: agitation, anxiety, increased excitability, sleep disturbance, hyperkinesia, tremor and symptoms of violations of the gastrointestinal tract.
rarely: withdrawal symptoms: panic attack, strong excitability, hallucinations, parasthesia, tinnitus and unusual symptoms from the side central nervous system.