|Trade names||Several trade names worldwide|
|Oral, powder for inhalation|
|ATC code||N05AH01 (WHO)|
|Metabolism||Extensive hepatic; active metabolites include amoxapine and 8-hydroxyloxapine. Inhibits P-gp and is a substrate of CYP1A2, CYP3A4 and CYP2D6<re name = "DrugPoint" />|
|Biological half-life||4 hours (oral); 7.61 hours (inhalation)|
|Excretion||Majority are excreted within 24 hours, main route through urine (conjugated metabolites), small amounts through the feces (unconjugated metabolites)|
|Chemical and physical data|
|Molar mass||327.808 g/mol|
|3D model (Jmol)||Interactive image|
|Melting point||109 to 110 °C (228 to 230 °F)|
|(what is this?)|
Loxapine (several trade names worldwide) is a typical antipsychotic medication, used primarily in the treatment of schizophrenia. The drug is a member of the dibenzoxazepine class and structurally related to clozapine (which belongs to the chemically akin class of dibenzodiazepines). Several researchers have argued that loxapine may behave as an atypical antipsychotic.
Therapeutic uses and dosages
The typical starting dosage is 10 mg twice daily; usual dose range 30–50 mg twice daily; maximum recommended dosage is 250 mg per day. The US Food and Drug Administration (FDA) has approved loxapine inhalation powder 10 mg (Adasuve, Alexza Pharmaceuticals) for the acute treatment of agitation associated with schizophrenia or bipolar I disorder in adults.
A brief review of loxapine found no conclusive evidence that it was particularly effective in patients with paranoid schizophrenia. A subsequent systematic review considered that the limited evidence did not indicate a clear difference in its effects from other antipsychotics.
- Taste sense altered (14%)
- Sedated (12%)
- Pharyngitis (3%)
- Dry mouth
- Intense Sleeping (Highest Percentage)
- Blurred Speech
- Extrapyramidal disease (dose-dependent. At lower dosages its propensity for causing extrapyramidal side effects appears to be similar to that of atypical antipsychotics
- Blurred vision
- Urinary retention
- Somnolence (which appears to be moderate in severity compared to other antipsychotic drugs)
- Nasal congestion
- Paralytic ileus
- Hepatocellular liver damage
- Neuroleptic malignant syndrome
- Tardive dyskinesia
- Transient ischaemic attack
|Molecular target||Binding affinity (Ki [nM]) for loxapine||Binding affinity (Ki [nM]) for amoxapine|
|5-HT2C||13.3||2 (Cloned rat receptor protein)|
|5-HT7||87.6||40.2 (Rat, Cloned)|
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- Product monograph from Medscape (free registration required).