II. Indications
- Panic Disorder
- Attention Deficit Hyperactivity Disorder
- Major Depression
- Nocturnal Enuresis (not first line agent)
III. Background
- See Tricyclic Antidepressant
- Imipramine was the prototypal, first marketed Tricyclic Antidepressant (first synthesized in 1951, released in 1957)
IV. Safety
- Unknown safety in pregnancy
- Safe in Lactation
V. Mechanism
- See Tricyclic Antidepressant
- Imipramine inhibits both Serotonin and Norepinephrine reuptake
- Imipramine is demethylated to Desipramine, which primarily inhibits Norepinephrine reuptake
VI. Pharmacokinetics
- Obtain serum levels in pediatric population
- Avoid as full dose Antidepressant
- Serum Half Life: 11 to 25 hours
- Therapeutic plasma level: 200 to 350
VII. Dosing: Major Depression
- Adults
- Start: 50 to 75 mg orally at bedtime (or divided twice daily)
- Titrate to 75 to 100 mg orally at bedtime (or divided twice daily)
- Maximum: 150 mg mg/day
- Therapeutic range 50 to 150 mg/day
- Teens and Elderly
- Start 30 to 40 mg orally at bedtime
- Advance to 50 to 100 mg orally daily or divided twice daily as tolerated and to effect
- Maximum: 100 mg/day
VIII. Dosing: Nocturnal Enuresis in Children
- Consider other measures for Nocturnal Enuresis first
- Consider baseline EKG before starting medication
- Initial dose
- Avoid in age <6 years
- Start at 10 mg orally nightly given one hour before bedtime
- Maximum dosing: up to 0.9 to 1.5 mg/kg
- Age 6-8 years
- May increase dose by 10 mg every 1-2 weeks as needed up to 25-50 mg per night one hour before bed
- Age 8-12 years
- May increase dose by 10 mg every 1-2 weeks as needed up to 50 mg per night one hour before bed
- Age over 12 years
- May increase dose by 10 mg every 1-2 weeks as needed up to 75 mg per night one hour before bed
- Age 6-8 years
- Discontinue after 3-6 months (some guidelines suggest maximum of 3 months)
- Taper to one half dose nightly for 2 weeks
- Taper to one half dose every other night for 2 weeks
IX. Efficacy: Nocturnal Enuresis
- Response in up to 60% of children
- Relapse is common soon after stopping medication
X. Adverse effects
- See Tricyclic Antidepressants
- Tricyclic Antidepressant Overdose
- Significant adverse effects
- Anticholinergic Symptoms
- Drowsiness (but less than with Amitriptyline)
- Sleep problems
- Gastrointestinal upset
- Orthostatic Hypotension
- Cardiac Arrhythmia (Quinidine-like effect)
- Weight gain
XI. Precautions
- See Tricyclic Antidepressants
- Serious cardiotoxicity in overdosage
XII. Resources
XIII. References
- (2023) Med Lett Drugs Ther 62(1592): 25-32
- Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 38-9
- Hamilton (2020) Tarascon Pocket Pharmacopoeia
- Thiedke (2003) Am Fam Physician 67:1499-510 [PubMed]
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Related Studies
| imipramine (on 9/21/2022 at Medicaid.Gov Survey of pharmacy drug pricing) | ||
| IMIPRAMINE HCL 10 MG TABLET | Generic | $0.09 each |
| IMIPRAMINE HCL 25 MG TABLET | Generic | $0.09 each |
| IMIPRAMINE HCL 50 MG TABLET | Generic | $0.14 each |
| IMIPRAMINE PAMOATE 75 MG CAP | Generic | $5.00 each |