Home Drug Guide Imipramine Pamoate

Drug Guide

Generic Name

Imipramine Pamoate

Brand Names Tofranil-PM

Classification

Therapeutic: Antidepressant, Tricyclic Antidepressant (TCA)

Pharmacological: Serotonin and Norepinephrine Reuptake Inhibitor with Anticholinergic Properties

FDA Approved Indications

  • Major depressive disorder
  • Enuresis (urinary incontinence, especially in children)

Mechanism of Action

Imipramine Pamoate inhibits reuptake of serotonin and norepinephrine in the central nervous system, increasing their levels in synaptic clefts. It also has anticholinergic and sedative effects, contributing to its therapeutic action and side effect profile.

Dosage and Administration

Adult: Typically 75-300 mg daily, divided into 1-3 doses; dosage adjusted based on response and tolerability.

Pediatric: For enuresis: 25-50 mg at bedtime, titrated as needed up to 75 mg.

Geriatric: Start at lower doses (e.g., 25-50 mg at bedtime) due to increased sensitivity and risk of side effects.

Renal Impairment: Use with caution; dosage adjustments may be necessary.

Hepatic Impairment: Use with caution; start at lower doses and monitor closely.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed; crosses the blood-brain barrier.

Metabolism: Primarily metabolized in the liver via CYP2D6 enzymes.

Excretion: Excreted primarily in urine.

Half Life: Approximately 8-16 hours, variable among individuals.

Contraindications

  • Known hypersensitivity to imipramine or other TCAs.
  • Recent myocardial infarction.
  • Use of monoamine oxidase inhibitors (MAOIs) within 14 days.

Precautions

  • History of seizures, bipolar disorder, glaucoma, urinary retention, QT prolongation, or suicidal ideation; monitor closely.

Adverse Reactions - Common

  • Dry mouth (Common)
  • Drowsiness (Common)
  • Dizziness (Common)
  • Constipation (Common)

Adverse Reactions - Serious

  • Cardiac arrhythmias (Rare but serious)
  • Suicidal thoughts or behavior (Monitor closely, especially in young adults and adolescents)
  • Serotonin syndrome (Rare)

Drug-Drug Interactions

  • Monoamine oxidase inhibitors (MAOIs)
  • Other serotonergic agents (SSRIs, SNRIs, triptans)
  • CNS depressants (alcohol, sedatives)
  • Cimetidine, quinidine

Drug-Food Interactions

  • Avoid alcohol and CNS depressant foods

Drug-Herb Interactions

  • St. John’s Wort, Ginseng

Nursing Implications

Assessment: Monitor mental health status, suicidal ideation, cardiac function (ECG), hepatic and renal functions.

Diagnoses:

  • Risk for suicidal ideation
  • Risk for cardiac arrhythmias

Implementation: Administer dose at bedtime to minimize sedative effects. Monitor for adverse effects and therapeutic efficacy.

Evaluation: Assess mood improvement and side effect occurrence.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Do not abruptly stop medication.
  • Report worsening mood, suicidal thoughts, or side effects.
  • Be cautious about driving or operating machinery until effects are known.

Special Considerations

Black Box Warnings:

  • Increased risk of suicidal thoughts and behavior in children, adolescents, and young adults.

Genetic Factors: CYP2D6 poor metabolizers may have increased plasma levels.

Lab Test Interference: Possible false results in certain cardiac assays.

Overdose Management

Signs/Symptoms: Agitation, confusion, hallucinations, seizures, arrhythmias, coma, hypotension.

Treatment: Supportive care, activated charcoal if early, cardiovascular monitoring, use of sodium bicarbonate for cardiac arrhythmias, and intensive care as needed.

Storage and Handling

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

Stability: Stable when stored properly.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.