1. Introduction
Dosulepin (also known as dothiepin) is a tricyclic antidepressant (TCA) used to treat depression and anxiety. It works by inhibiting the reuptake of serotonin and norepinephrine, increasing their levels in the brain. Dosulepin is considered effective for treating major depressive disorders but is typically reserved for cases where other antidepressants are unsuitable due to safety concerns and side effect profiles.
2. Indications
- Approved Indications:
- Depression (especially with associated anxiety).
- Off-Label Uses:
- Chronic pain conditions (e.g., neuropathic pain).
3. Dosage
- Adults:
- Starting dose: 25–50 mg at bedtime.
- Maintenance dose: 75–150 mg daily (typically given as a single dose at bedtime).
- Maximum dose: 150 mg daily.
- Elderly:
- Start with 25 mg at bedtime.
- Gradually titrate up if needed, not exceeding 75 mg daily.
- Children:
- Not recommended for use in children or adolescents under 18 years.
4. Administration
- Take orally at the same time each day, preferably at bedtime due to its sedative effects.
- Swallow tablets whole with water.
5. Forms Available
- Tablets: 25 mg, 50 mg.
- Capsules: 25 mg.
6. Side Effects
6.1. Common Side Effects
- Drowsiness or sedation.
- Dry mouth.
- Dizziness.
- Weight gain.
- Constipation.
6.2. Less Common Side Effects
- Blurred vision.
- Difficulty urinating.
- Sweating.
6.3. Rare but Serious Side Effects
- Cardiac arrhythmias (prolonged QT interval).
- Seizures.
- Hepatotoxicity.
- Suicidal ideation or behaviour (particularly in younger patients).
7. Warnings
- Cardiac Risk: Dosulepin is associated with an increased risk of arrhythmias, particularly in overdose or patients with pre-existing heart conditions.
- Suicidal Thoughts: Increased risk in young adults, adolescents, and children. Monitor closely during the initial weeks of therapy.
- Overdose Risk: High toxicity in overdose; symptoms include seizures, arrhythmias, and coma.
8. Precautions
- Use cautiously in patients with a history of cardiovascular disease, epilepsy, or bipolar disorder.
- Avoid abrupt discontinuation to minimise withdrawal symptoms (e.g., nausea, headache, and anxiety).
- Not recommended for use in patients with severe liver disease.
9. Interactions
- Drug-Drug Interactions:
- Monoamine oxidase inhibitors (MAOIs): Contraindicated due to risk of serotonin syndrome.
- CNS depressants (e.g., alcohol, benzodiazepines): Increased risk of sedation.
- Anticholinergic drugs (e.g., atropine): Increased risk of side effects like dry mouth and constipation.
- Antiarrhythmic drugs: Increased risk of QT prolongation.
- Drug-Food Interactions:
- Alcohol may enhance sedative effects.
10. Monitoring Parameters
- Monitor for therapeutic response and signs of side effects.
- ECG in patients with pre-existing cardiac conditions or those taking high doses.
- Observe for worsening depression or suicidal ideation, especially in younger adults.
11. Use in Children
- Not recommended for children under 18 years due to a lack of safety data and an increased risk of suicidal thoughts.
12. Use in Pregnancy
- Category C: Use only if benefits outweigh risks. Limited evidence suggests potential harm to the foetus.
13. Use in Elderly
- Use cautiously due to increased sensitivity to side effects, especially sedation and cardiovascular risks. Start with a lower dose and titrate slowly.
14. Use in Kidney Disease
- Dose adjustments are not typically required, but use with caution in severe renal impairment.
15. Use in Liver Disease
- Use with caution in patients with liver impairment, as metabolism of dosulepin may be reduced.
16. Patient Counselling Points
- Take dosulepin at bedtime to minimise daytime drowsiness.
- Avoid alcohol while on this medication.
- Do not stop taking dosulepin suddenly without consulting your doctor.
- Report symptoms such as palpitations, fainting, or worsening depression immediately.
- Inform your healthcare provider about all other medications you are taking.
17. Table of Brand Names, Manufacturers, and Prices
Brand Name | Manufacturer | Price (USD) |
---|---|---|
Prothiaden | Abbott Laboratories | $20–40 (30 tablets, 25 mg) |
Generic Dosulepin | Various | $10–25 (30 tablets, 25 mg) |
18. FAQs (15 Questions)
- What is dosulepin used for?
Dosulepin is used to treat depression and anxiety. - How does dosulepin work?
It increases the levels of serotonin and norepinephrine in the brain by inhibiting their reuptake. - Can dosulepin cause drowsiness?
Yes, drowsiness is a common side effect, which is why it is typically taken at bedtime. - Is dosulepin safe for long-term use?
It can be used long-term under medical supervision, but regular monitoring for side effects is essential. - Can dosulepin cause heart problems?
Yes, it may cause arrhythmias, especially in patients with pre-existing heart conditions or in overdose. - How should dosulepin be taken?
Take it once daily at bedtime as prescribed by your doctor. - What should I do if I miss a dose of dosulepin?
Take it as soon as you remember, but skip it if it’s close to the next dose. Do not double the dose. - Can dosulepin be taken during pregnancy?
It is not generally recommended during pregnancy unless the benefits outweigh the risks. - Does dosulepin interact with other medications?
Yes, it interacts with MAOIs, CNS depressants, and anticholinergic drugs. - What are the signs of dosulepin overdose?
Overdose symptoms include seizures, confusion, arrhythmias, and coma. Seek immediate medical attention. - Can children take dosulepin?
It is not recommended for children under 18 years. - Can dosulepin cause withdrawal symptoms?
Yes, abrupt discontinuation can lead to symptoms such as nausea, headache, and anxiety. - Can dosulepin be taken with alcohol?
No, alcohol may enhance the sedative effects of dosulepin. - How long does dosulepin take to work?
It may take 2–4 weeks for noticeable improvements in symptoms. - How should dosulepin be stored?
Store at room temperature, away from light and moisture.