Drug Guide
Trimipramine Maleate
Classification
Therapeutic: Antidepressant
Pharmacological: Tricyclic Antidepressant (TCA)
FDA Approved Indications
- Major depressive disorder
Mechanism of Action
Trimipramine acts by inhibiting the reuptake of norepinephrine and serotonin in the central nervous system, and also has sedative properties due to its antihistaminic activity.
Dosage and Administration
Adult: Initially, 100-150 mg/day in divided doses, titrated up to 300 mg/day as needed.
Pediatric: Not approved for pediatric use.
Geriatric: Start at lower doses, monitor closely due to increased sensitivity.
Renal Impairment: Adjust dose based on clinical response and tolerability.
Hepatic Impairment: Use with caution, lower doses recommended.
Pharmacokinetics
Absorption: Well absorbed orally.
Distribution: Widely distributed with protein binding approximately 85%.
Metabolism: Metabolized in the liver mainly via CYP2D6; active metabolites formed.
Excretion: Excreted primarily in the urine.
Half Life: Approximately 20-40 hours.
Contraindications
- Recent myocardial infarction
- Use concomitantly with MAO inhibitors
- History of hypersensitivity to TCAs
Precautions
- Use cautiously in patients with glaucoma, urinary retention, history of seizure disorders, or cardiovascular disease. Monitor for suicidal thoughts, especially in young adults.
Adverse Reactions - Common
- Dry mouth (Common)
- Sedation (Common)
- Dizziness (Common)
- Constipation (Common)
Adverse Reactions - Serious
- Arrhythmias (Rare)
- Seizures (Rare)
- Suicidal thoughts or behaviors (Monitor closely, especially in young adults.)
Drug-Drug Interactions
- Monoamine oxidase inhibitors (risk of serotonin syndrome), other serotonergic agents, other CNS depressants, anticholinergic drugs.
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor mental status, suicidal ideation, cardiovascular status, and signs of anticholinergic effects.
Diagnoses:
- Risk for injury related to orthostatic hypotension
- Impaired skin integrity due to anticholinergic effects
Implementation: Administer at bedtime if sedative effects are desired. Monitor for adverse reactions.
Evaluation: Assess depressive symptoms, side effects, and overall response to therapy.
Patient/Family Teaching
- Do not discontinue abruptly. Report side effects such as irregular heartbeat, seizures, or severe allergic reactions.
- Avoid alcohol and other CNS depressants.
- Take medication as prescribed, usually at bedtime.
- Inform about potential anticholinergic effects like dry mouth, constipation.
Special Considerations
Black Box Warnings:
- Increased risk of suicidal thoughts and behaviors in children, adolescents, and young adults.
Genetic Factors: Metabolism affected by CYP2D6 enzyme polymorphisms, influencing drug levels.
Lab Test Interference: Possibly affects blood glucose and thyroid function tests.
Overdose Management
Signs/Symptoms: Seizures, hallucinations, hot dry skin, tachycardia, arrhythmias, coma.
Treatment: Supportive care, Activated charcoal if recent ingestion, alkalinization of urine, available specific antidotes are limited; cardiac monitoring essential.
Storage and Handling
Storage: Store at room temperature away from moisture, light, and children.
Stability: Stable under recommended storage conditions.