Drug | Effective dose | Comments |
First-line therapy |
Antiseizure medications | | - Can cause dizziness and sedation; minimize with slow titration
- Use lower doses for older patients
- Avoid concomitant use with opioids; can cause respiratory depression
|
Gabapentin | - IR: 300 to 1200 mg orally three times daily
- ER: 600 to 1800 mg orally twice daily
| - Initiate treatment at a low dose (typically 300 mg orally at night), increasing gradually until pain relief or limiting side effects occur
|
Pregabalin | - 150 to 300 mg orally twice daily
| - Initiate treatment at low dose (typically 150 mg orally at night)
|
Antidepressants |
Serotonin-noradrenaline reuptake inhibitors |
Duloxetine | - IR: 60 to 120 mg orally once daily
| |
Venlafaxine | - ER:75 to 225 mg orally once daily
| |
Tricyclic antidepressants (TCAs) | | - Initiate treatment at low dose, increase slowly at weekly intervals
- May take 6 to 8 weeks, including 2 weeks at highest tolerated dose, for adequate trial
|
Nortriptyline | - 25 to 75 mg orally once daily
| - Preferred among TCAs due to less sedation and fewer anticholinergic effects
|
Amitriptyline | - 25 to 125 mg orally once daily
| |
Second-line therapy |
Capsaicin 8% patch | - 1 to 4 patches to painful area for 30 to 60 minutes every three months
| - For peripheral pain
- Long term safety not established
|
Lidocaine patch | - 1 to 3 patches to painful area for ≤12 hours in a 24 hour period, patch-free period of ≥12 hours
| |
Tramadol | - IR: 100 to 200 mg orally three times daily
- ER: 100 to 200 mg orally twice daily
| |
Third-line therapy |
Botulinum toxin A | - 50 to 200 units subcutaneously to painful area every 3 months
| - Specialist use, for peripheral pain
|
Strong opioids | | - Not routinely used for chronic pain
- Use only at lowest effective dose, after risk assessment, and with ongoing assessment of risks and benefits
- Use in combination with nonpharmacologic and nonopioid pharmacologic therapy
|