NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine

NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine

Introduction

Loxapine is a tricyclic antipsychotic medication used in the treatment of schizophrenia. As a conventional antipsychotic, this drug helps to treat schizophrenia by decreasing the level of excitement in the brain (Lebel et al., 2023). Excitement in this case means excessive brain activity that are involved in emotion, perception, and thought processing. Overactivity in the brain in schizophrenia is caused by excess dopamine in the brain. It is a first-generation drug that can be taken orally and nasally through inhalation.

Brand names: Adasuve, Loxitane

Off-label use: Psychosis in Parkinson’s, mania in bipolar, treatment-resistant depression.

FDA Approved use: Acute agitation in schizophrenia and bipolar I, schizophrenia.

 

 

Classification

Loxapine is a first-generation antipsychotic. This means that it is an older medication that was developed in the 1950s for the treatment of psychosis.

Sub-classification: Loxapine is a dibenzoxazepine derivative. Dibenzoxazepine is a class of compounds which is used as an incapacitating agent. Loxapine is a molecule derived from this compound and is targeted for psychosis therapy NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine

 

 

 

III.
         Mechanism of Action

Loxapine is a dopamine antagonist and a serotonin 5-HT2 blocker.

It blocks the effects of dopamine in the brain by blocking the D2 receptors, which reduces brain activity in dopaminergic pathways. These pathways are involved in psychotic symptoms such as hallucinations and delusions.

It also blocks serotonin 5-HT2 receptors, which brings about a therapeutic effect on the patient.

 

Pharmacokinetics

After oral administration, sedation begins in 30 minutes, with peak concentration of the drug in 1.5 to 3hours. The duration of sedation lasts about 12 hours after administration. Rate of drug metabolism is contingent on route of administration. It is more rapidly absorbed orally through the GI tract and completely absorbed through IV.

Loxapine is metabolized in the liver through aromatic hydroxylation and N-oxidation to a variety of metabolites.

It is excreted through the urine and feces.

Its half-life is 5 hours at initial phase and 19 hours at terminal phase.

 

Dosing and Administration

Typical adult doses are about 10mg taken twice daily and can be increased gradually. The total daily dosage is about 60mg to 100mg per day based on response to the drug and tolerance (Im et al., 2023).

The drug is often taken by mouth and in capsules. There is also the inhalation form by Adasuve for incidents of acute agitation in the patient. Inhalation delivers the medication faster than the oral route through the lungs.

For patients with liver or kidney complications, the dosing can be adjusted. This may also be adjusted for older adults, who then require lower doses to avoid toxicity and side effects.

Loxapine should be taken at the same time daily to ensure the body has steady levels of the drug (Nuss et al., 2022). Inconsistent timing or missing doses may lead to a relapse of symptoms or an increase in the side effects of the drug.

 

 

VII. Special Populations

Older adults- Loxapine should be cautiously administered to older adults because of their increased risk of falls, sedation, and confusion.

Children and adolescents – The drug is typically not recommended for this age group as safety is yet to be established (Im et al., 2023).

Pregnant women- There is a risk of neonatal complications, such as withdrawal symptoms in the newborn, and therefore loxapine must be cautiously administered (Merino et al., 2022).

Suicidal patients- Those with active suicidal ideation should receive loxapine cautiously. Loxapine can increase impulsivity and cause mood changes, leading to heightened suicidal ideation.

 

VIII. Half-Life

The half-life of a medication is the amount of time it takes for half of the drug to be eliminated from the body. This helps determine how often a drug needs to be taken and how long it stays effective in the system (Im et al., 2023).

It is crucial for the clinician to understand the half-life concept as this determines the dosage of the drug administered. A longer half-life means smaller and less frequent dosage because the drug is in the system for longer.

Loxapine’s half-life is between 4 and 8 hours, with 7-hydroxyloxapine, a metabolite that has a longer effect and contributes to the 12 to 24-hour duration of antipsychotic dynamics NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine

 

 

 

 

IX:
Side Effects and Adverse Reactions

Drowsiness or sedation – feeling sleepy or sluggish.

Dry mouth – decreased saliva production

Constipation – due to slowed gastrointestinal movement (Merino et al., 2022).

Blurred vision – usually temporary

Dizziness or lightheadedness, especially when standing up quic

Seizures – especially at high doses or in those with seizure disorders.

Severe hypotension – low blood pressure that can lead to fainting.

 

 

Clinical Concerns with Extrapyramidal Symptoms (EPS) and Tardive Dyskinesia (TD)

EPS

Acute dystonia: painful muscle stiffness, especially in the neck and face.

Akathisia: feeling restless or unable to sit still

Parkinsonism: tremors, slow movement, and stiffness like Parkinson’s disease (Fadem & Citrome, 2019).

Bradykinesia: slowness in movement.

Tardive Dyskinesia (TD)

Repetitive, involuntary movements—especially of the mouth, tongue, face, or limbs (Im et al., 2023).

Movements may look like lip-smacking, blinking, or twitching

Can occur after months or years of treatment

Risk Factors:

Long-term use of antipsychotics

Higher doses

Older adults

Female patients

History of mood disorders

Screening Tools to Detect EPS and TD

AIMS (Abnormal Involuntary Movement Scale) – helps detect TD.

SAS (Simpson-Angus Scale) – for Parkinsonian symptoms.

BARS (Barnes Akathisia Rating Scale) – for restlessness and akathisia.

NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine

Contraindications and Significant Drug Interactions:

Hypersensitivity

Respiratory issues for the inhaled version.

History of seizures (Fadem & Citrome, 2019).

Drug to Drug interactions

Alcohol, opioids, benzodiazepines

Anticholinergics

Macrolides, citalopram (Fadem & Citrome, 2019).

Patient must:

Avoid alcohol

Monitor ECG if combining with other QT-prolonging medications (Fadem & Citrome, 2019).

Use extra caution in polypharmacy, especially in older adults.

 

 

 

References

Faden, J., & Citrome, L. (2019). Examining the safety, efficacy, and patient acceptability of inhaled loxapine for the acute treatment of agitation associated with schizophrenia or bipolar I disorder in adults. Neuropsychiatric disease and treatment, 15, 2273–2283.
https://doi.org/10.2147/NDT.S173567

Im, D. S., Capitanov, M., & VandenBerg, A. M. (2023). Loxapine in the treatment of manic and psychotic symptoms in an individual intolerant to multiple Mood-Stabilizing and antipsychotic medications. Case Reports in Psychiatry, 2023, 1–11.
https://doi.org/10.1155/2023/8887553

Lebel, C., Endomba, F. T., Chabridon, G., & Chauvet-Gélinier, J. (2023). Efficacy and safety of loxapine in acute agitation. The Primary Care Companion for CNS Disorders, 25(6).
https://doi.org/10.4088/pcc.23r03552

Merino, D., Fernandez, A., Gérard, A. O., Ben Othman, N., Rocher, F., Askenazy, F., Verstuyft, C., Drici, M.-D., & Thümmler, S. (2022). Adverse Drug Reactions of Olanzapine, Clozapine and Loxapine in Children and Youth: A Systematic Pharmacogenetic Review. Pharmaceuticals, 15(6), 749.
https://doi.org/10.3390/ph15060749

Nuss, P., Corruble, E., Baloche, E., Garay, R. P., & Llorca, P. (2022). Fifty years of experience with loxapine for the rapid non-coercive tranquilization of acute behavioral disturbances in schizophrenia patients, and beyond. Expert Review of Neurotherapeutics, 22(8), 639–653.
https://doi.org/10.1080/14737175.2022.2108706
  NURS-6630 Week 7: Discussion/Assignment: Patient Medication Guide Loxapine