The most reported Adverse Drug Reactions (ADRs) with Quetiapine are somnolence, dizziness, dry mouth, withdrawal (discontinuation) symptoms, elevations in serum triglyceride levels, elevation in total cholesterol (predominantly LDL cholesterol), decrease in HDL cholesterol, weight gain, decreased haemoglobin and extrapyramidal symptoms.
Blood and lymphatic system disorders: Very common: Decreased haemoglobin.
Common: Leucopenia, decreased neutrophil count, eosinophils increased.
Uncommon: Thrombocytopenia, anemia, platelet count decreased.
Immune system disorders: Uncommon: Hypersensitivity (including allergic skin reactions).
Very rare: Anaphylactic reaction.
Endocrine disorders: Common: Hyperprolactinaemia, decreases in total T4, decreases in free T4, decreases in total T3, increases in TSH.
Uncommon: Decreases in free T3, hypothyroidism.
Very rare: Inappropriate antidiuretic hormone secretion.
Metabolism and nutritional disorders: Very common: Elevations in serum triglyceride levels, elevations in total cholesterol (predominantly LDL cholesterol), decreases in HDL cholesterol, weight gain.
Common: Increased appetite, blood glucose increased to hyperglycaemic levels.
Uncommon: Hyponatraemia, diabetes mellitus.
Rare: Metabolic syndrome.
Psychiatric disorders: Common: Abnormal dreams and nightmares, suicidal ideation and suicidal behaviour.
Rare: Somnambulism and related reactions such as sleep talking and sleep related eating disorder.
Nervous system disorders: Very common: Dizziness, somnolence, headache, extrapyramidal symptoms.
Uncommon: Seizure, restless legs syndrome, tardive dyskinesia, syncope.
Cardiac disorders: Common: Tachycardia, palpitations.
Uncommon: QT prolongation, bradycardia.
Eye disorders: Common: Vision blurred.
Vascular disorders: Common: Orthostatic hypotension.
Rare: Venous thromboembolism.
Respiratory, thoracic and mediastinal disorder: Common: Dyspnoea.
Gastrointestinal disorders: Very common: Dry mouth.
Common: Constipation, dyspepsia, vomiting.
Rare: Pancreatitis, intestinal obstruction/ileus.
Hepato-biliary disorders: Common: Elevations in ALT, elevations in gamma-GT levels.
Uncommon: Elevations in AST.
Rare: Jaundice, hepatitis (with or without jaundice).
Skin and subcutaneous tissue disorders: Very rare: Angioedema, Stevens-Johnson syndrome.
Unknown: Toxic Epidermal Necrolysis, erythema multiforme.
Musculoskeletal and connective tissue disorders: Very rare: Rhabdomyolysis.
Pregnancy, puerperium and perinatal conditions: Unknown: Drug withdrawal syndrome neonatal.
Reproductive system and breast disorders: Uncommon: Sexual dysfunction.
Rare: Priapism, galactorrhoea, breast swelling, menstrual disorder.
General disorders and administration site conditions: Very common: Withdrawal (discontinuation) symptoms.
Common: Mild asthenia, peripheral oedema, irritability, pyrexia.
Rare: Neuroleptic malignant syndrome, hypothermia.
Renal and urinary disorders: Uncommon: Urinary retention.
Investigations: Rare: Elevations in blood creatine phosphokinase.
Cases of QT prolongation, ventricular arrhythmia, sudden unexplained death, cardiac arrest and torsades de pointes have been reported with the use of neuroleptics and rare considered class effects.