Doxepin's effects on chronic pain and depression: a controlled study

Area of Science:

• Psychiatry
• Pain Management
• Pharmacology

Background:

• Chronic pain, particularly of the low back or cervical spine, frequently co-occurs with clinical depression, complicating treatment.
• Effective management strategies for patients experiencing both chronic pain and depression are crucial.

Purpose of the Study:

• To evaluate the efficacy and safety of doxepin in treating patients with chronic low back or cervical spine pain and concomitant depression.
• To compare the effects of doxepin versus placebo on depression scores, pain severity, and related functional impairments.

Main Methods:

• A 6-week, randomized, double-blind, placebo-controlled trial involving sixty patients with chronic pain and depression.
• Patients received either doxepin or a placebo, with assessments including Hamilton depression scores and Global Assessment Scale scores.
• Pain severity, duration, and impact on activity, sleep, and muscle tension were also evaluated.

Main Results:

• The doxepin group showed significant improvements in Hamilton depression scores and Global Assessment Scale scores compared to placebo.
• Significant reductions in pain severity, percentage of time pain was felt, and improvements in activity, sleep, and muscle tension were observed in the doxepin group.
• Improvements were noted as early as week 1, with maximal effects at week 6, at a mean doxepin dosage of approximately 200 mg/day.

Conclusions:

• Doxepin is an effective and safe treatment option for patients suffering from chronic pain and co-existing depression.
• The study supports the use of doxepin in managing multifaceted symptoms associated with chronic pain and depressive disorders.
• No significant changes in plasma beta-endorphin or enkephalin-like activity were observed, suggesting the therapeutic effects are not mediated by these pathways.