Clozapineside effects
clozapine 25 MG Disintegrating Oral Tablet
Adverse reactions
The following adverse reactions are discussed in more detail in other sections of the labeling: Severe Neutropenia Orthostatic Hypotension, Bradycardia, and Syncope Falls Seizures Myocarditis, Pericarditis, and Cardiomyopathy and Mitral Valve Incompetence Increased Mortality in Elderly Patients with Dementia-Related Psychosis Gastrointestinal Hypomotility with Severe Complications Eosinophilia QT Interval Prolongation Metabolic Changes (Hyperglycemia and Diabetes Mellitus, Dyslipidemia, and Weight Gain) Neuroleptic Malignant Syndrome Hepatotoxicity Fever Pulmonary Embolism Anticholinergic Toxicity Interference with Cognitive and Motor Performance Tardive Dyskinesia Patients with Phenylketonuria Cerebrovascular Adverse Reactions Recurrence of Psychosis and Cholinergic Rebound after Abrupt Discontinuation Most common adverse reactions (≥5%) were: CNS reactions (sedation, dizziness/vertigo, headache, and tremor); cardiovascular reactions (tachycardia, hypotension, and syncope); autonomic nervous system reactions (hypersalivation, sweating, dry mouth, and visual disturbances); gastrointestinal reactions (constipation and nausea); and fever. To report SUSPECTED ADVERSE REACTIONS, contact Teva at 1-888-838-2872 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
6.1 Clinical
Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The most commonly reported adverse reactions (≥5%) across clozapine clinical trials were: CNS reactions, including sedation, dizziness/vertigo, headache, and tremor; cardiovascular reactions, including tachycardia, hypotension, and syncope; autonomic nervous system reactions, including hypersalivation, sweating, dry mouth, and visual disturbances; gastrointestinal reactions, including constipation and nausea; and fever. Table 9 summarizes the most commonly reported adverse reactions (≥5%) in clozapine-treated patients (compared to chlorpromazine-treated patients) in the pivotal, 6-week, controlled trial in treatment-resistant schizophrenia.
Table 9: Common Adverse Reactions (≥5%) in the 6-Week, Randomized, Chlorpromazine-Controlled Trial in Treatment-Resistant Schizophrenia Clozapine Chlorpromazine Adverse Reaction (N=126) (N=142) (%) (%) Sedation 21 13 Tachycardia 17 11 Constipation 16 12 Dizziness 14 16 Hypotension 13 38 Fever (hyperthermia) 13 4 Hypersalivation 13 1 Hypertension 12 5 Headache 10 10 Nausea/vomiting 10 12 Dry mouth 5 20 Table 10 summarizes the adverse reactions reported in clozapine-treated patients at a frequency of 2% or greater across all clozapine studies (excluding the 2 year InterSePT™ Study). These rates are not adjusted for duration of exposure.
Table 10: Adverse Reactions (≥2%) Reported in Clozapine-treated Patients (N=842) Across all Clozapine Studies (excluding the 2 year InterSePT™ Study) Body System Clozapine Adverse Reaction N=842 Percentage of Patients Central Nervous System Drowsiness/Sedation 39 Dizziness/Vertigo 19 Headache 7 Tremor 6 Syncope 6 Disturbed Sleep/Nightmares 4 Restlessness 4 Hypokinesia/Akinesia 4 Agitation 4 Seizures (convulsions) 3 † Rigidity 3 Akathisia 3 Confusion 3 Fatigue 2 Insomnia 2 Cardiovascular Tachycardia 25 † Hypotension 9 Hypertension 4 Gastrointestinal Constipation 14 Nausea 5 Abdominal Discomfort/Heartburn 4 Nausea/Vomiting 3 Vomiting 3 Diarrhea 2 Urogenital Urinary abnormalities 2 Autonomic Nervous System Salivation 31 Sweating 6 Dry mouth 6 Visual disturbances 5 Skin Rash 2 Hemic/Lymphatic Leukopenia/Decreased WBC/Neutropenia 3 Miscellaneous Fever 5 Weight Gain 4 † Rate based on population of approximately 1700 exposed during premarket clinical evaluation of clozapine. Table 11 summarizes the most commonly reported adverse reactions (≥10% of the clozapine or olanzapine group) in the InterSePT™ Study. This was an adequate and well-controlled, two-year study evaluating the efficacy of clozapine relative to olanzapine in reducing the risk of suicidal behavior in patients with schizophrenia or schizoaffective disorder. The rates are not adjusted for duration of exposure.
Table 11: Incidence of Adverse Reactions in Patients Treated with Clozapine or Olanzapine in the InterSePT™ Study (≥10% in the clozapine or olanzapine group) Clozapine Olanzapine N=479 N=477 Adverse Reactions % Reporting % Reporting Salivary hypersecretion 48% 6% Somnolence 46% 25% Weight increased 31% 56% Dizziness (excluding vertigo) 27% 12% Constipation 25% 10% Insomnia 20% 33% Nausea 17% 10% Vomiting 17% 9% Dyspepsia 14% 8% Dystonia Class effect: Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment.
Dystonic symptoms include: spasm of the neck muscles, sometimes progressing to tightness of the throat, swallowing difficulty, difficulty breathing, and/or protrusion of the tongue. While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups.
6.2 Postmarketing
Experience The following adverse reactions have been identified during post-approval use of clozapine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Central Nervous System Delirium, EEG abnormal, myoclonus, paresthesia, possible cataplexy, status epilepticus, obsessive compulsive symptoms, and post-discontinuation cholinergic rebound adverse reactions. Cardiovascular System Atrial or ventricular fibrillation, ventricular tachycardia, QT interval prolongation, Torsades de Pointes, myocardial infarction, cardiac arrest, pericarditis, and periorbital edema. Endocrine System Pseudopheochromocytoma. Gastrointestinal System Acute pancreatitis, dysphagia, salivary gland swelling, megacolon, fecal incontinence, and intestinal ischemia, infarction, perforation, ulceration or necrosis. Hepatobiliary System Cholestasis, hepatitis, jaundice, hepatotoxicity, hepatic steatosis, hepatic necrosis, hepatic fibrosis, hepatic cirrhosis, liver injury (hepatic, cholestatic, and mixed), and liver failure. Immune System Disorders Angioedema, leukocytoclastic vasculitis. Urogenital System Acute interstitial nephritis, nocturnal enuresis, priapism, and renal failure. Skin and Subcutaneous Tissue Disorders Hypersensitivity reactions: photosensitivity, vasculitis, erythema multiforme, skin pigmentation disorder, and Stevens-Johnson Syndrome. Musculoskeletal System and Connective Tissue Disorders Myasthenic syndrome, rhabdomyolysis, and systemic lupus erythematosus. Respiratory System Aspiration, pleural effusion, pneumonia, lower respiratory tract infection. Hemic and Lymphatic System Mild, moderate, or severe leukopenia, agranulocytosis, granulocytopenia, WBC decreased, deep-vein thrombosis, elevated hemoglobin/hematocrit, erythrocyte sedimentation rate (ESR) increased, sepsis, thrombocytosis, and thrombocytopenia. Vision Disorders Narrow-angle glaucoma. Miscellaneous Creatine phosphokinase elevation, hyperuricemia, hyponatremia, and weight loss.
Text above is quoted in full from the FDA-approved drug label published by openFDA, effective June 24, 2025. Matched to this product by RxNorm code. Cross-references to other sections of the full prescribing information have been removed, since they point to a document not shown here. Nothing else is changed: no sentence is shortened, reworded or summarised.
Contraindications
Clozapine ODT is contraindicated in patients with a history of serious hypersensitivity to clozapine (e.g., photosensitivity, vasculitis, erythema multiforme, or Stevens-Johnson Syndrome) or any other component of Clozapine ODT. Known hypersensitivity to clozapine or any other component of Clozapine ODT
Text above is quoted in full from the FDA-approved drug label published by openFDA, effective June 24, 2025. Matched to this product by RxNorm code. Cross-references to other sections of the full prescribing information have been removed, since they point to a document not shown here. Nothing else is changed: no sentence is shortened, reworded or summarised.
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