The pregabalin clinical programme involved over 8,900 patients exposed to pregabalin, of whom over 5,600 were in double-blind placebo-controlled trials. The most commonly reported adverse reactions were dizziness and somnolence. Adverse reactions were usually mild to moderate in intensity. In all controlled studies, the discontinuation rate due to adverse reactions was 12% for patients receiving pregabalin and 5% for patients receiving placebo. The most common adverse reactions resulting in discontinuation from pregabalin treatment groups were dizziness and somnolence.
In the list as follows all adverse reactions, which occurred at an incidence greater than placebo and in more than one patient, are listed by class and frequency (very common (≥1/10); common (≥1/100 to <1/10): uncommon (≥1/1,000 to <1/100); rare (≥1/10,000 to <1/1,000); very rare (<1/10,000), not known (cannot be estimated from the available data). Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.
The adverse reactions listed may also be associated with the underlying disease and/or concomitant medicinal products.
Additional reactions reported from post-marketing experience are included in the list as follows.
Infections and infestations: Common: Nasopharyngitis
Blood and lymphatic system disorders: Uncommon: Neutropenia
Immune system disorders: Uncommon: Hypersensitivity. Rare: Angioedema, allergic reaction
Metabolism and nutrition disorders: Common: Appetite increased. Uncommon: Anorexia, hypoglycaemia.
Psychiatric disorders: Common: Euphoric mood, confusion, irritability, disorientation, insomnia, libido decreased. Uncommon: Hallucination, panic attack, restlessness, agitation, depression. depressed mood, elevated mood, aggression, mood swings, depersonalisation, word finding difficulty, abnormal dreams, libido increased, anorgasmia, apathy. Rare: Disinhibition.
Nervous system disorders: Very common: Dizziness, somnolence, headache. Common: Ataxia, coordination abnormal, tremor, dysarthria, amnesia, memory impairment, disturbance in attention, paraesthesia, hypoaesthesia, sedation, balance disorder, lethargy. Uncommon: Syncope, stupor, myoclonus, loss of consciousness, psychomotor hyperactivity, dyskinesia, dizziness postural, intention tremor, nystagmus, cognitive disorder, mental impairment, speech disorder, hyporeflexia, hyperaesthesia, burning sensation, ageusia, malaise. Rare: Convulsions, parosmia, hypokinesia, dysgraphia.
Eye disorders: Common: Vision blurred, diplopia. Uncommon: Peripheral vision loss, visual disturbance, eye swelling, visual field defect, visual acuity reduced, eye pain, asthenopia, photopsia, dry eye, lacrimation increased, eye irritation. Rare: Vision loss, keratitis, oscillopsia, altered visual depth perception, mydriasis, strabismus, visual brightness
Ear and labyrinth disorders: Common: Vertigo. Uncommon: Hyperacusis.
Cardiac disorders: Uncommon: Tachycardia, atrioventricular block first degree, sinus bradycardia, congestive heart failure. Rare: QT prolongation, sinus tachycardia, sinus arrhythmia.
Vascular disorders: Uncommon: Hypotension, hypertension, hot flushes, flushing, peripheral coldness.
Respiratory, thoracic and mediastinal disorders: Uncommon: Dyspnoea, epistaxis, cough, nasal congestion, rhinitis, snoring, nasal dryness. Rare: Pulmonary oedema, throat tightness.
Gastrointestinal disorders: Common: Vomiting, nausea, constipation, diarrhoea, flatulence, abdominal distension, dry mouth. Uncommon: Gastroesophageal reflux disease, salivary hypersecretion, hypoaesthesia oral. Rare: Ascites, pancreatitis, swollen tongue, dysphagia.
Skin and subcutaneous tissue disorders: Uncommon: Rash papular, urticaria, hyperhidrosis, pruritus. Rare: Stevens Johnson syndrome, cold sweat.
Musculoskeletal and connective tissue disorders: Common: Muscle cramp, arthralgia, back pain, pain in limb, cervical spasm. Uncommon: Joint swelling, myalgia, muscle twitching, neck pain, muscle stiffness. Rare: Rhabdomyolysis.
Renal and urinary disorders: Uncommon: Urinary incontinence, dysuria. Rare: Renal failure, oliguria, urinary retention.
Reproductive system and breast disorders: Common: Erectile dysfunction. Uncommon: Sexual dysfunction, ejaculation delayed, dysmenorrhoea, breast pain. Rare: Amenorrhoea, breast discharge, breast enlargement, gynaecomastia.
General disorders and administration site conditions: Common: Oedema peripheral, oedema, gait abnormal, fall, feeling drunk, feeling abnormal, fatigue. Uncommon: Generalised oedema, face oedema, chest tightness, pain, pyrexia, thirst, chills, asthenia.
Investigations: Common: Weight increased. Uncommon: Blood creatine phosphokinase increased, alanine aminotransferase increased, aspartate aminotransferase increased, blood glucose increased, platelet count decreased, blood creatinine increased, blood potassium decreased, weight decreased. Rare: White blood cell count decreased.
After discontinuation of short-term and long-term treatment with pregabalin withdrawal symptoms have been observed in some patients.
The following reactions have been mentioned: insomnia, headache, nausea, anxiety, diarrhoea, flu syndrome, convulsions, nervousness, depression, pain, hyperhidrosis and dizziness, suggestive of physical dependence.
The patient should be informed about this at the start of the treatment.
Concerning discontinuation of long-term treatment of pregabalin, data suggest that the incidence and severity of withdrawal symptoms may be dose-related.
Paediatric population: The pregabalin safety profile observed in two paediatric studies (pharmacokinetic and tolerability study, n=65; 1 year open label follow on safety study, n=54) was similar to that observed in the adult studies (see Pharmacology: Pharmacodynamics and Pharmacokinetics under Actions and Dosage & Administration).