What is the use of Doxepin (tricyclic antidepressant)?

From the Guidelines

Doxepin is primarily used to treat depression, anxiety disorders, and insomnia, with a recommended dose of 3-6 mg for insomnia, taken 30 minutes before bedtime, as supported by recent guidelines 1.

Key Points

• Doxepin works by increasing levels of neurotransmitters like serotonin and norepinephrine in the brain, which helps regulate mood and sleep.
• For depression and anxiety, typical dosing ranges from 75-150 mg daily, often starting at a lower dose of 25-50 mg and gradually increasing.
• Common side effects include drowsiness, dry mouth, constipation, blurred vision, and urinary retention.
• Patients should be aware that doxepin can cause significant sedation, so activities requiring alertness should be avoided until tolerance develops.
• The medication should not be stopped abruptly as withdrawal symptoms may occur; dosage should be gradually reduced under medical supervision.
• Doxepin should be used cautiously in elderly patients and those with heart conditions, glaucoma, urinary retention, or seizure disorders, as noted in recent studies 1.

Important Considerations

• Doxepin may interact with many medications, particularly MAO inhibitors, which should not be taken within 14 days of doxepin.
• Full therapeutic effects for depression may take 2-3 weeks to develop, so patience is important when beginning treatment.
• Recent guidelines recommend using doxepin at the lowest effective dose and for the shortest possible duration to minimize the incidence of adverse events 1.

From the FDA Drug Label

Doxepin Hydrochloride Capsules, USP are recommended for the treatment of:

1. Psychoneurotic patients with depression and/or anxiety.
2. Depression and/or anxiety associated with alcoholism (not to be taken concomitantly with alcohol).
3. Depression and/or anxiety associated with organic disease (the possibility of drug interaction should be considered if the patient is receiving other drugs concomitantly).
4. Psychotic depressive disorders with associated anxiety including involutional depression and manic-depressive disorders

The use of Doxepin, a tricyclic antidepressant, is for the treatment of:

• Depression and/or anxiety in psychoneurotic patients
• Depression and/or anxiety associated with alcoholism, organic disease, or psychotic depressive disorders 2

From the Research

Use of Doxepin

• Doxepin is a tricyclic antidepressant that combines antidepressant activity with a sedative effect, making it useful in treating depression, particularly in patients with sleep disturbances and anxiety 3.
• The medication has been found to be effective in improving sleep quality in patients with comorbid insomnia and anxiety disorders, with low-dose doxepin (12.5 mg/day) showing significant improvements in sleep latency, duration, and disturbances 4.
• Doxepin has also been used in the treatment of insomnia, with low-dose doxepin (3 mg and 6 mg) showing significant reductions in waking after sleep onset and increases in total sleep time, particularly in older adults 5.
• The medication's sedative properties make it more useful than imipramine in depressed patients with sleep disturbances and in depression associated with anxiety, although benzodiazepines remain the drugs of choice in anxiety states 3.
• Doxepin has been found to have a favorable adverse event profile, with common side effects including dry mouth, drowsiness, and constipation, and postural hypotension being uncommon 3.

Therapeutic Efficacy

• Doxepin's mood-elevating effect appears to be similar to that of amitriptyline, but is probably less marked than that of imipramine, and may be slower to take effect than imipramine 3.
• The medication has been found to be effective in treating depression, with a similar overall response rate to other tricyclic antidepressants, but with fewer or less troublesome side effects 3.
• Doxepin has also been found to be effective in improving anxiety symptoms in patients with comorbid insomnia and anxiety disorders 4.

Dosage and Administration

• Low-dose doxepin (12.5 mg/day) has been found to be effective in improving sleep quality in patients with comorbid insomnia and anxiety disorders 4.
• Ultra-low-dose doxepin (≤6 mg) has been found to be effective in treating insomnia in older adults, with significant reductions in waking after sleep onset and increases in total sleep time 5.
• Doxepin is usually well tolerated, and in particular by the elderly and those with cardiovascular disease, although it can cause significant cardiovascular side effects in overdose 3.