Tofranil-PM

Generic name:

Imipramine hydrochloride

Drug class:

Tricyclic antidepressant (TCA)

Dosage form:

Extended-release capsules (PM); immediate-release tablets (varies by formulation)

Root of administration:

Oral

Dose:

• Adults (depression): initial 75 mg once daily at bedtime (extended-release), may increase to 150–200 mg/day
• Children (enuresis; immediate-release): 1–2 mg/kg/day in divided doses
• Maximum: up to 300 mg/day (varies by indication; consult label)

Mechanism of action:

Blocks reuptake of norepinephrine and serotonin by inhibiting transporter proteins; exhibits anticholinergic, antihistaminic and alpha-adrenergic blocking effects.

Drug usage cases:

• Major depressive disorder
• Nocturnal enuresis (immediate-release)
• Off-label: chronic neuropathic pain
• Off-label: panic disorder
• Off-label: migraine prophylaxis
• Off-label: attention-deficit/hyperactivity disorder (ADHD)
• Off-label: bulimia nervosa

Drug contra indications:

• Hypersensitivity to imipramine or other TCAs
• Concurrent use or use within 14 days of MAO inhibitors
• Acute recovery phase following myocardial infarction
• Uncontrolled narrow-angle glaucoma
• Urinary retention or severe prostatic hypertrophy
• Severe liver disease
• Manic phase of bipolar disorder

Side effects:

• Dry mouth
• Blurred vision
• Constipation
• Urinary retention
• Orthostatic hypotension
• Tachycardia
• ECG changes (QT prolongation, arrhythmias)
• Weight gain
• Sedation
• Dizziness
• Confusion
• Tremor
• Headache
• Excessive sweating
• Sexual dysfunction (decreased libido, erectile dysfunction)
• Seizures (dose-related)
• Blood dyscrasias (rare)
• Photosensitivity reactions

Warnings:

• Increased risk of suicidal thinking and behavior in children, adolescents and young adults
• Risk of arrhythmias and orthostatic hypotension; monitor cardiovascular status
• Anticholinergic effects may precipitate glaucoma, urinary retention, constipation
• May lower seizure threshold
• Potential for severe withdrawal symptoms on abrupt discontinuation; taper gradually
• Monitor for activation of mania or hypomania
• Caution in elderly (risk of falls, cognitive impairment)
• Numerous drug interactions (e.g., SSRIs, anticholinergics, CNS depressants)

Use during pregnancy or breastfeeding:

Pregnancy Category C: animal studies have shown adverse fetal effects; use only if benefit justifies risk. Excreted in breast milk; risk of anticholinergic and cardiac effects in nursing infant. Monitor neonate for feeding difficulties, sedation and cardiac complications.