Clinical Overview
Clomipramine is a tricyclic antidepressant specifically indicated for obsessive-compulsive disorder (OCD). It is considered one of the most effective treatments for OCD and is often preferred over other tricyclics due to its superior efficacy for obsessive-compulsive symptoms, though it has significant side effects that require careful monitoring.
Primary Clinical Applications
Clomipramine is the gold standard tricyclic for OCD treatment and has demonstrated superior efficacy compared to other tricyclics for this indication. It may also be used off-label for depression, panic disorder, and other anxiety disorders when OCD features are prominent.
Mechanism and Clinical Benefits
Clomipramine potently inhibits serotonin reuptake (more so than other tricyclics) in addition to norepinephrine reuptake. This dual mechanism, with particular serotonergic activity, accounts for its unique efficacy in OCD treatment. It also has significant anticholinergic, antihistaminergic, and alpha-adrenergic blocking properties.
Clinical Considerations
Clomipramine requires gradual dose titration to minimize side effects, particularly gastrointestinal symptoms. It has a higher incidence of sexual side effects compared to other tricyclics and may cause significant weight gain. Therapeutic drug monitoring may be helpful to optimize dosing and minimize toxicity.
Prescribing Information
Dosing & Administration
Obsessive-Compulsive Disorder – Adults:
- Initial: 25 mg daily at bedtime
- Titration: Increase gradually to 100 mg daily over 2 weeks
- Range: 100-250 mg daily
- Maximum: 250 mg daily
- Maintenance: Usually 100-150 mg daily
Children and Adolescents (≥10 years):
- Initial: 25 mg daily
- Titration: Increase gradually over 2 weeks to 3 mg/kg/day or 100 mg daily (whichever is smaller)
- Maximum: 3 mg/kg/day or 200 mg daily
Administration:
- Take with meals to reduce GI upset
- May give entire dose at bedtime once stabilized
- Divide doses during titration period
Indications
- Obsessive-compulsive disorder (adults and children ≥10 years)
- Off-label: Depression with OCD features, panic disorder
Contraindications
- Hypersensitivity to tricyclic antidepressants
- Use within 14 days of MAOI therapy
- Acute recovery period following myocardial infarction
- Concurrent use with linezolid or IV methylene blue
Warnings & Precautions
- Boxed Warning: Increased risk of suicidal thoughts and behavior in patients under 25 years
- Cardiovascular effects: Monitor ECG in patients with cardiac disease
- Seizure risk: Dose-related, particularly >250 mg daily
- Anticholinergic effects: Significant – dry mouth, constipation, urinary retention
- Sexual dysfunction: High incidence, may affect compliance
- Weight gain: Significant risk with long-term use
Drug Interactions
- MAOIs: Contraindicated – risk of serotonin syndrome
- CYP2D6 inhibitors: Significantly increase clomipramine levels
- CNS depressants: Enhanced sedation
- Anticholinergic drugs: Additive anticholinergic effects
- Type 1C antiarrhythmics: Additive cardiac effects
Adverse Reactions
Common (>10%):
- Dry mouth, constipation, nausea, dyspepsia
- Somnolence, dizziness, tremor, nervousness
- Sexual dysfunction, weight gain
Serious:
- Cardiac arrhythmias, seizures (dose-related), severe anticholinergic toxicity
Special Populations
- Elderly: Start with lower doses, monitor for anticholinergic effects
- CYP2D6 poor metabolizers: Require significantly lower doses
- Pregnancy: Category C – use only if benefits outweigh risks
- Therapeutic monitoring: May be helpful to optimize dosing