about Quetiapine class, uses, side effects contraindications
Quetiapine
Short Description
Quetiapine is an anticonvulsant drug of unknown etiology used to treat?schizophrenia?, manic episodes of bipolar disorder, and depression.
The efficacy of quetiapine in treating the symptoms of schizophrenia is similar to that of haloperidol, except that it causes fewer side effects, especially those that affect movement, such as Parkinsonism, and does not cause a sharp rise in the proportion of the hormone prolactin (Prolactin hormone), which makes its symptoms less Leakage of breast milk and the disappearance of menstruation.
Category
Chemical class: Dibenzothiazepine derivative
Therapeutic class: Antipsychotic
Pregnancy category: C
Indications
To treat schizophrenia
Adults. Initial: 25 mg b.i.d. on day 1. Increased by 25 to 50 b.i.d. or t.i.d. on days 2 and 3. Usual: 300 to 400 mg daily by day 4, in divided doses b.i.d. or t.i.d. Increased every 2 days in increments of 25 to 50 mg b.i.d., as needed. Maximum: 800 mg daily.
Adults. Initial: 300 mg once daily in evening. Dosage increased daily in increments up to 300 mg, as needed. Maximum: 800 mg daily. To manage psychotic disorders other than schizophrenia
Adults. Initial: 25 mg b.i.d. on day 1. Dosage increased by 25 to 50 mg b.i.d. or t.i.d. on days 2 and 3. Usual: 300 to 400 mg daily by day 4, in divided doses b.i.d. or t.i.d. Dosage increased every 2 days in increments of 25 to 50 mg b.i.d., as needed. Maximum: 800 mg daily. To treat depressive episodes in bipolar disorder
Adults. Initial: On day one, 50 mg once at bedtime; day two, 100 mg once at bedtime; day three, 200 mg once at bedtime; day four, 300 mg once at bedtime. Maintenance: 300 mg once daily at bedtime.
Adults. Initial: 50 mg once daily in evening on day 1, followed by 100 mg once daily in evening on day 2, 200 mg once daily in evening on day 3, and 300 mg once daily in evening on day 4 and thereafter. As adjunct therapy with antidepressants to treat major depressive disorder
Adults. Initial: 50 mg once daily in evening, increased to 150 mg once daily in evening on day 3. Maximum: 300 mg daily in evening. To treat acute manic episodes in bipolar I disorder
Adults. 50 mg b.i.d., increased to 200 mg b.i.d on day 4 (in increments no greater than 100 mg daily) and then further increased to 400 mg b.i.d. on day 6 (in increments no greater than 200 mg daily), as needed. To treat acute manic episodes in bipolar I disorder as monotherapy; as adjunct with lithium or divalproex to treat acute manic episodes in bipolar I disorder
Adults. Initial: 300 mg once daily in evening on day 1, followed by 600 mg once daily in evening on day 2 and 200 to 400 mg b.i.d. on day 3 and thereafter. Maintenance: 200 to 400 mg b.i.d.
DOSAGE ADJUSTMENT For elderly patients and patients with hepatic impairment, initial dosage no higher than 50 mg once daily and increased in increments of 50 mg/day depending on response and tolerance.
Mechanism of Action
May produce antipsychotic effects by interfering with dopamine binding to dopamine type 2 (D2)-receptor sites in the brain and by antagonizing serotonin 5-HT2, dopamine type 1 (D1), histamine H1, and adrenergic alpha1and alpha2receptors.
Contraindications
Hypersensitivity to quetiapine or its components
Interactions
antihypertensives: Possibly enhanced antihypertensive effects of these cimetidine, erythromycin, fluconazole, itraconazole,
ketoconazole: Decreased clearance and possibly increased effects of quetiapine
CNS depressants: Possibly increased CNS depression lorazepam: Possibly increased effects of lorazepam phenytoin, thioridazine: Increased clearance and possibly decreased effectiveness of quetiapine
alcohol use: Possibly enhanced CNS depression
Side Efect
CNS: Depression, dizziness, drowsiness, dystonia, extrapyramidal reactions, hypertonia, lethargy, restless leg syndrome, somnolence, suicidal ideation, tardive dyskinesia
CV: Cardiomyopathy, hypercholesterolemia, myocarditis, orthostatic hypotension, palpitations
EENT: Dry mouth, nasal congestion, pharyngitis, rhinitis
ENDO: Hyperglycemia, syndrome of inappropriate ADH secretion
GI: Anorexia, constipation, indigestion
HEME: Agranulocytosis, leukopenia, neutropenia
MS: Dysarthria, muscle weakness, rhabdomyolysis
RESP: Cough, dyspnea
SKIN: Diaphoresis, Stevens-Johnson syndrome
Other: Anaphylaxis, flulike symptoms, weight gain
Cautions
WARNING Quetiapine shouldn’t be used for elderly patients with dementia-related psychosis because drug increases the risk of death in these patients.
Monitor patients (particularly young adults) closely for suicidal tendencies, especially when therapy starts or dosage changes, because depression may worsen temporarily during these times.
WARNING Monitor patient taking quetiapine for predisposing factors for neuroleptic malignant syndrome, such as heat stress, physical exhaustion, dehydration, and organic brain disease. Neuroleptic malignant syndrome includes hyperpyrexia, muscle rigidity, altered mental status, and autonomic instability (which may include irregular pulse or blood pressure, tachycardia, diaphoresis, and arrhythmias). Monitor patient for signs of tardive dyskinesia, a potentially irreversible complication characterized by involuntary, dyskinetic movements of tongue, mouth, jaw, eyelids, or face. Notify prescriber if such signs develop because quetiapine therapy may need to be stopped. Monitor patient for orthostatic hypotension, especially during initial dosage titration period. Be prepared to correct underlying conditions, such as hypovolemia and dehydration, before starting quetiapine therapy, as prescribed. Monitor patient for prolonged abnormal muscle contractions, especially during the first few days of quetiapine therapy, in male patients, and in younger patients. Assess patient for hypothyroidism because drug can cause dose-dependent decreases in total and free thyroxine (T4) levels. Monitor laboratory results during first 3 weeks of therapy for transient elevations in hepatic enzyme levels. Notify prescriber if they persist or worsen. Monitor patient’s blood glucose and lipid levels routinely, as ordered, because drug increases the risk of hyperglycemia and hypercholesterolemia. Check CBC often during the first few months of therapy, as ordered, in patients with a low white blood cell count or a history of drug-induced hematologic problems. If counts drop or patient develops a fever or other signs of infection, notify prescriber and expect to discontinue drug and provide supportive care. PATIENT SAFTY
Instruct patient to take quetiapine with food to reduce stomach upset. Advise patient not to stop taking quetiapine suddenly because doing so may exacerbate his symptoms. Inform patient that quetiapine therapy may cause dizziness or drowsiness. Advise him not to drive or perform other activities that require alertness until drug’s full CNS effects are known. Instruct patient to rise slowly from a seated or lying position to reduce the risk of dizziness or fainting. Caution patient to avoid consuming alcoholic beverages because they can increase dizziness and drowsiness. Urge family or caregiver to watch patient closely for suicidal tendencies, especially when therapy starts or dosage changes and particularly if patient is a young adult. Encourage patient on long-term therapy to have regular eye examinations so that cataracts can be detected.
trad drugs based on Quetiapine
| Gen name | Trade name | Catagory name |
| Quetiapine | SEROQUEL 100 MG TAB | |
| Quetiapine | SEROQUEL 200 MG TAB | |
| Quetiapine | SEROQUEL 25 MG TAB | |
| Quetiapine | SEROQUEL 300MG FC TABS | |
| Quetiapine | SEROQUEL STARTER PACK 10 TABLETS | |
other drugs from same cataogory
| Gen name | trade name | catogry |