Home Drug Guide Loxapine Succinate

Drug Guide

Generic Name

Loxapine Succinate

Brand Names Loxitane

Classification

Therapeutic: Antipsychotic

Pharmacological: First-generation (typical) antipsychotic

FDA Approved Indications

Schizophrenia

Mechanism of Action

Loxapine blocks specific dopamine D2 receptor sites in the brain, which helps to reduce psychotic symptoms. It also has some antagonistic activity at serotonin and adrenergic receptors.

Dosage and Administration

Adult: Typically 10-50 mg two to three times daily, adjusted based on response and tolerability.

Pediatric: Not commonly used in pediatric patients; consult specialist for specific cases.

Geriatric: Use with caution; start at lower end of dosing range due to increased sensitivity.

Renal Impairment: Adjustment may be needed; closely monitor response.

Hepatic Impairment: Use with caution; dose adjustment may be required.

Pharmacokinetics

Absorption: Well absorbed orally

Distribution: Widely distributed in body tissues, crosses the blood-brain barrier

Metabolism: Primarily hepatic via CYP1A2 and CYP2D6 enzymes

Excretion: Primarily via urine as metabolites; some fecal excretion

Half Life: Approximately 10-30 hours, variable depending on individual.

Contraindications

Known hypersensitivity to loxapine or other phenothiazines.
Blockage of certain heart rhythm abnormalities (e.g., QT prolongation).

Precautions

History of seizure disorders.
Elderly patients with dementia-related psychosis treated with antipsychotics are at increased risk of death; use with caution. Monitor for neuroleptic malignant syndrome and extrapyramidal symptoms.

Adverse Reactions - Common

Drowsiness, sedation (Common)
Extrapyramidal symptoms (EPS) (Common)
Dry mouth (Common)
Constipation (Common)

Adverse Reactions - Serious

Neuroleptic malignant syndrome (Rare)
Tardive dyskinesia (Less common with long-term use)
QT prolongation, cardiac arrhythmias (Rare)
Seizures (Rare)

Drug-Drug Interactions

CNS depressants (additive sedation)
Other medications prolonging QT interval (e.g., certain antiarrhythmics, antibiotics)
Other antipsychotics

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor mental status, observe for signs of EPS, tardive dyskinesia, and neuroleptic malignant syndrome. Regularly check cardiac status, including EKG if indicated.

Diagnoses:

Risk for falls due to sedation or orthostatic hypotension
Risk for peripheral anticholinergic effects

Implementation: Administer with food to decrease GI upset. Monitor for adverse effects, especially in elderly.

Evaluation: Assess improvement in psychotic symptoms, monitor for adverse effects, and adjust dose accordingly.

Patient/Family Teaching

Do not operate machinery until you know how this medication affects you.
Report any signs of involuntary movements or muscle stiffness.
Avoid alcohol and other CNS depressants.
Follow dosing schedule closely.

Special Considerations

Black Box Warnings:

Increased mortality in elderly patients with dementia-related psychosis.
Risk of suicidal thoughts and behaviors in children, adolescents, and young adults.

Genetic Factors: Metabolism via CYP1A2; genetic variations may affect drug levels.

Lab Test Interference: May alter certain laboratory tests, including liver function tests.

Overdose Management

Signs/Symptoms: Severe EPS, sedation, hypotension, seizures, coma.

Treatment: Supportive care, monitor vital signs, activated charcoal if recent ingestion, and manage complications per standard protocols.

Storage and Handling

Storage: Store at room temperature, away from light and moisture.

Stability: Stable under recommended storage conditions.