Usage
Opipramol is prescribed for the treatment of generalized anxiety disorder (GAD) and somatoform disorders. It is classified as a tricyclic antidepressant (TCA) with anxiolytic properties. Its mechanism of action involves modulating sigma-1 receptors, and antagonizing histamine H1, serotonin 5-HT2, dopamine D2 and α1-adrenergic receptors. This multifaceted receptor activity contributes to its anxiolytic and mild antidepressant effects.
Alternate Names
While “Opipramol” is the common generic name, “Opipramol dihydrochloride” or “Opipramol hydrochloride” may also be used. Brand names include Insidon®, Pramolan®, and Ensidon®. Availability may vary in different regions.
How It Works
Pharmacodynamics: Opipramol primarily acts as an anxiolytic and exhibits mild antidepressant activity. It modulates sigma-1 receptors, and antagonizes H1, 5-HT2, D2, and α1 receptors. It does not significantly inhibit serotonin or norepinephrine reuptake, unlike typical TCAs.
Pharmacokinetics:
- Absorption: Opipramol is well-absorbed from the gastrointestinal tract.
- Metabolism: Primarily hepatic metabolism, likely involving CYP2D6.
- Elimination: Renal excretion.
Dosage
Standard Dosage
Adults:
Initial: 50 mg twice or three times daily.
Maintenance: Dosage can range from 50 mg to 300 mg daily, adjusted based on individual response and tolerability. In severe cases, the dose can be increased up to 100 mg three times daily.
Children:
6 years: 3 mg/kg body weight daily, divided into multiple doses. Pediatric use should be closely monitored due to limited clinical experience in this population.
Special Cases:
- Elderly Patients: Start with a lower dose (e.g., 25 mg twice daily) and titrate cautiously.
- Patients with Renal Impairment: Dose adjustment is recommended, although specific guidelines are not universally established. Close monitoring is advised.
- Patients with Hepatic Dysfunction: Initiate with a reduced dose and titrate carefully. Monitor liver function.
- Patients with Comorbid Conditions: Exercise caution in patients with cardiovascular disease, prostatic hypertrophy, glaucoma, or a history of seizures.
Clinical Use Cases
Opipramol’s primary use is in the management of GAD and somatoform disorders. It is not typically indicated for specific clinical scenarios like intubation, surgical procedures, mechanical ventilation, ICU use, or emergency situations.
Dosage Adjustments
Dosage should be adjusted based on individual patient response, tolerability, renal or hepatic function, and potential drug interactions.
Side Effects
Common Side Effects
Drowsiness, dizziness, dry mouth, constipation, blurred vision, weight gain.
Rare but Serious Side Effects
Orthostatic hypotension, confusion, cardiac arrhythmias, seizures.
Contraindications
Absolute contraindications include hypersensitivity to opipramol, acute alcohol intoxication, barbiturate or benzodiazepine intoxication, severe hepatic impairment, severe renal impairment, glaucoma, urinary retention, prostatic hypertrophy, intestinal obstruction, and predisposition to seizures.
Drug Interactions
Opipramol may interact with other CNS depressants (alcohol, benzodiazepines, opioids), antihypertensives (guanethidine, clonidine), and drugs metabolized by CYP2D6 (fluoxetine, paroxetine). It can also interact with some anticholinergics. Concomitant use with MAOIs should be avoided.
Pregnancy and Breastfeeding
Opipramol’s safety during pregnancy and breastfeeding has not been fully established. Use only if the potential benefit outweighs the potential risk to the fetus or neonate.
Drug Profile Summary
- Mechanism of Action: Modulates sigma-1 receptors and antagonizes H1, 5-HT2, D2, and α1 receptors.
- Side Effects: Drowsiness, dizziness, dry mouth, constipation. Rarely: hypotension, confusion, arrhythmias, seizures.
- Contraindications: Hypersensitivity, acute intoxication with alcohol, barbiturates, or benzodiazepines, severe hepatic or renal impairment, glaucoma, urinary retention.
- Drug Interactions: CNS depressants, antihypertensives, CYP2D6 inhibitors/inducers.
- Pregnancy & Breastfeeding: Use with caution; safety not fully established.
- Dosage: Adults: 50–300 mg/day; children: 3 mg/kg/day.
- Monitoring Parameters: Monitor for adverse effects, especially in elderly patients and those with comorbidities.
Popular Combinations
Opipramol is not generally used in combination with other psychotropic medications for synergistic effects. Treatment is usually initiated with opipramol as monotherapy and adjusted as needed based on individual response.
Precautions
Standard precautions include screening for allergies, assessing hepatic and renal function, and evaluating for pre-existing conditions like glaucoma, prostatic hypertrophy, and seizure disorders. Caution is advised in pregnant/breastfeeding women, children, and the elderly. Patients should avoid alcohol and activities requiring alertness.
FAQs
Q1: What is the recommended dosage for Opipramol?
A: Adults: Initially 50 mg two or three times daily, adjustable up to 300 mg/day. Children (>6 years): 3 mg/kg/day. Elderly and patients with hepatic/renal impairment: lower initial dose and cautious titration.
Q2: What are the common side effects?
A: Drowsiness, dizziness, dry mouth, constipation, blurred vision are common.
Q3: How does Opipramol work?
A: It affects multiple neurotransmitter systems, primarily acting as a sigma-1 receptor agonist and an antagonist of H1, 5-HT2, D2, and α1 receptors.
Q4: Is Opipramol safe during pregnancy?
A: Safety during pregnancy and breastfeeding is not fully established. Use only if potential benefit outweighs risk.
Q5: What are the contraindications for Opipramol use?
A: Hypersensitivity, acute intoxication with alcohol, barbiturates, or benzodiazepines, severe hepatic or renal impairment, glaucoma, urinary retention, prostatic hypertrophy, and predisposition to seizures.
Q6: Can Opipramol be used with other antidepressants?
A: Combining Opipramol with other antidepressants, especially MAOIs, can be risky. Consult a specialist before combining such medications.
Q7: How long does it take for Opipramol to work?
A: Anxiolytic effects might be noticeable within 1-2 weeks, but full therapeutic benefit may take up to 4 weeks.
Q8: What should patients know about taking Opipramol?
A: Take as prescribed, do not abruptly discontinue, inform your doctor about all other medications, and avoid alcohol. Report any unusual symptoms.
Q9: Is Opipramol addictive?
A: Opipramol is not considered addictive, but withdrawal symptoms may occur upon abrupt discontinuation. Gradual tapering is recommended.
