Drug Guide
Maprotiline Hydrochloride
Classification
Therapeutic: Antidepressant, Tricyclic
Pharmacological: Tetracyclic antidepressant
FDA Approved Indications
- Major depressive disorder
Mechanism of Action
Maprotiline primarily inhibits the reuptake of norepinephrine and, to a lesser extent, serotonin, increasing their levels in the synaptic cleft. It also has antihistaminic and anticholinergic properties.
Dosage and Administration
Adult: Initially 25 mg three times daily; dosage may be increased gradually based on response and tolerability, typical maintenance dose ranges from 75 to 150 mg per day, divided into doses.
Pediatric: Not approved for pediatric use; safety and efficacy not established.
Geriatric: Start at lower doses due to increased sensitivity; monitor closely.
Renal Impairment: Use with caution; dose adjustments may be necessary.
Hepatic Impairment: Use with caution; dose adjustments may be necessary.
Pharmacokinetics
Absorption: Well absorbed after oral administration.
Distribution: Widely distributed, crosses the blood-brain barrier.
Metabolism: Metabolized in the liver via CYP450 enzymes.
Excretion: Excreted mainly in urine as metabolites.
Half Life: Approximately 14-16 hours.
Contraindications
- History of hypersensitivity to maprotiline or other tetracyclic antidepressants.
- Recent myocardial infarction.
- Concurrent use with MAO inhibitors due to risk of severe reactions.
Precautions
- Use cautiously in patients with history of seizure disorders, urinary retention, glaucoma, or bipolar disorder. Monitor for suicidal ideation and behavior.
Adverse Reactions - Common
- Drowsiness (Frequent)
- Dry mouth (Frequent)
- Dizziness (Frequent)
- Constipation (Frequent)
Adverse Reactions - Serious
- Seizures (Rare)
- Arrhythmias (Rare)
- Suicidal thoughts or behavior (Monitor closely)
Drug-Drug Interactions
- CNS depressants, anticoagulants, other CNS-active drugs, MAO inhibitors.
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor mental status, suicidal thoughts, and cardiac status. Assess for signs of anticholinergic toxicity.
Diagnoses:
- Risk for injury related to sedation, arrhythmias.
- Impaired urinary elimination.
Implementation: Administer doses with meals if GI upset occurs. Gradually taper when discontinuing.
Evaluation: Assess mood improvement and monitor for adverse effects.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Do not stop abruptly to avoid withdrawal symptoms.
- Report any signs of worsening depression, suicidal ideation, or adverse effects.
- Avoid alcohol and CNS depressants.
- Be aware of possible anticholinergic side effects.
Special Considerations
Black Box Warnings:
- Increased risk of suicidal thinking and behavior in children, adolescents, and young adults in the first few months of therapy.
Genetic Factors: None well established.
Lab Test Interference: Potential effects on hepatic function tests; monitor as appropriate.
Overdose Management
Signs/Symptoms: Seizures, coma, hypotension, arrhythmias, respiratory depression.
Treatment: Supportive care, activated charcoal, gastric lavage if recent ingestion, cardiovascular monitoring, and treatment of seizures. No specific antidote.
Storage and Handling
Storage: Store at room temperature away from light and moisture.
Stability: Stable under recommended storage conditions.