Imipramine
TOFRANIL
What it isTertiary-amine tricyclic blocking serotonin and norepinephrine reuptake; depression and panic disorder.
Why this oneIts established use for childhood nocturnal enuresis distinguishes it from most other antidepressants, despite safer alternatives.
What limits itAnticholinergic and orthostatic effects limit use, and sodium-channel blockade makes overdose potentially fatal.
FDA-approved for
- depression (1959)
- childhood enuresis (~1973)
Off-label
- panic disorder
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Depression — outpatients | Adults | 75 mg/day | 150 mg/day | 200 mg/day |
| Depression — hospitalized | Adults | 100–150 mg/day | 200 mg/day | 250–300 mg/day |
| Depression — maintenance | Adults | 75–150 mg/day | ||
| Depression | Adolescent/Geriatric | 25–50 mg/day (as imipramine HCl tablets) | up to 100 mg/day | 100 mg/day |
Titration Hospitalized: if no response after 2 weeks, may increase to 250–300 mg/day
Renal Undefined
Hepatic Undefined
Instructions
- Total daily dose may be given once daily at bedtime; divided dosing if needed
- At least 14 days between an MAOI and imipramine (both directions)
- Following remission, gradually decrease the dose
- Antidepressant effect may take 1–3 weeks
Contraindications
- MAOIs (concurrently or within 14 days) due to risk of serotonin syndrome
- Acute recovery period after myocardial infarction
Cautions
- Clinical worsening and suicide risk
- Serotonin syndrome with serotonergic drugs (linezolid, IV methylene blue)
- Anticholinergic effects (urinary retention, angle-closure glaucoma)
- Cardiovascular — arrhythmias, orthostatic hypotension, conduction effects
- Lowered seizure threshold
Adverse reactions
- Orthostatic hypotension
- Anticholinergic effects (dry mouth, blurred vision, constipation, urinary retention)
- Confusional states (esp. elderly)
- Drowsiness/dizziness
- Tremor/seizures
- Weight change
- Bone marrow depression (rare)
Pregnancy Use only if clinical condition clearly justifies potential fetal risk; congenital malformations reported
Lactation Undefined
⚠ BOXED WARNING
- Suicidal thoughts and behaviors in patients under 25
Cost, est. cash$10–$300/month
Generic entry2010
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityAnticholinergic effects and cardiac sodium-channel blockade make overdose rapidly life-threatening.
Active metabolites
Mechanism of action: Imipramine ballicule
Open Imipramine in the interactive console ↗
Memory aids: mascots and interaction avatars
oldest tricycle → oldest tricyclic antidepressant (TCA)
