Dosing and uses of Loxitane (loxapine)
Adult dosage forms and strengths
capsule
- 5mg
- 10mg
- 25mg
- 50mg
Schizophrenia
Initial: 10-25 mg PO q12hr
Maintenance: 60-100 mg/day divided q6-12hr; not to exceed 250 mg/day
Pediatric dosage forms and strengths
Not recommended
Loxitane (loxapine) adverse (side) effects
Frequency not defined
Common
- Hypotension, Orthostatic hypotension
- Akathisia, dizziness, drug-induced tardive dystonia, dystonia, extrapyramidal disease, parkinsonian, somnolence, tardive dyskinesia
- Diminished sweating
- Constipation, xerostomia
- Blurred vision
- Urinary retention
- Nasal congestion
Serious
- Prolonged QT interval, torsades de pointes
- Ineffective thermoregulation, heatstroke or hypothermia (rare), neuroleptic malignant syndrome (rare), seizure (rare)
- Paralytic ileus (rare)
- Agranulocytosis (rare), disorder of hematopoietic structure (rare), leukopenia (rare), thrombocytopenia (rare)
- Cholestatic jaundice syndrome (rare)
- Drug-induced lupus erythematosus, systemic (rare)
- Priapism (rare)
Warnings
Black box warnings
Patients with dementia-related psychosis who are treated with antipsychotic drugs are at an increased risk of death as shown in short-term controlled trials. The deaths appeared to be either cardiovascular (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature.
This drug is not approved for the treatment of patients with dementia-related psychosis.
Contraindications
Documented hypersensitivity; severe CNS depression; severe liver or cardiac disease, bone marrow suppression; narrow-angle glaucoma
CNS depression (including coma), neuroleptic malignant syndrome (NMS), poorly controlled seizure disorder
Cautions
Caution in patients with cardiovascular disease or seizures; watch for hypotension if administering IM; in patients taking benzodiazepines, loxapine should be preceded by stopping benzodiazepine therapy for 2 weeks to avoid drug interactions capable of respiratory depression
FDA Warning regarding off-label use for dementia in elderly
Pregnancy and lactation
Pregnancy category: C
Neonates exposed to antipsychotic drugs during the 3rd trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery
These complications vary in severity; in some cases, symptoms have been self-limited, while in other cases neonates have required intensive care unit support and prolonged hospitalization
Lactation: avoid in breastfeeding
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Loxitane (loxapine)
Mechanism of action
Dibenzoxazepine antipsychotic; blocks mesolimbic D1 and D2 receptors in the brain; also has anti-serotonin 5HT2 activity
Pharmacokinetics
Half-Life: 4-12 hr
Duration: 12 hr
Onset: 20-30 min
Peak plasma time: 1-2 hr (PO); 5 hr (IM)
Peak plasma concentration: 0.006-0.013 mcg/mL
Metabolism: Aromatic hydroxylation, N-demethylation, N-oxidation
Metabolites: 8-hydroxyloxapine, 7-hydroxyloxapine
Excretion: Urine (56-70%), feces