What additional medication can be added to control pain in a patient with lumbosacral radiculopathy, anxiety, and inadequate pain relief, currently taking gabapentin, acetaminophen (Tylenol 650), naproxen (Aleve), and tramadol?

Management of Lumbosacral Radiculopathy Pain with Inadequate Relief

For a patient with lumbosacral radiculopathy, anxiety, and inadequate pain relief (8/10) despite current medications and lumbar epidural, duloxetine (an SNRI) should be added to the treatment regimen as the next medication of choice.

Current Medication Assessment

The patient is currently taking:

• Gabapentin (calcium channel α2-δ ligand)
• Acetaminophen (Tylenol 650mg)
• Naproxen (Aleve, an NSAID)
• Tramadol (weak opioid with SNRI properties)

Despite this combination and a lumbar epidural, the patient continues to have severe pain (8/10) and anxiety.

Recommended Medication Addition

First-Line Option: Duloxetine (SNRI)

• Duloxetine 30mg once daily for 1 week, then increase to 60mg once daily 1
• Rationale:
  • Demonstrated efficacy in neuropathic pain 1
  • Additional benefit for comorbid anxiety 1
  • Simpler dosing than other options (once daily) 1
  • Complementary mechanism to current medications 1
  • Lower risk of adverse effects compared to TCAs 1

Alternative Options (if duloxetine is contraindicated):

1. Secondary Amine TCA (Nortriptyline or Desipramine)

   • Starting at low dose (10-25mg) at bedtime with slow titration 1
   • Benefits: Effective for neuropathic pain and may help with sleep
   • Cautions: Anticholinergic side effects, cardiac toxicity concerns, requires ECG monitoring if patient is over 40 1

2. Pregabalin

   • Starting at 75mg twice daily, may increase to 150mg twice daily within a week 2
   • Benefits: FDA-approved for neuropathic pain, may be more effective than gabapentin in short-term 3
   • Consider: Patient is already on gabapentin; switching rather than adding may be preferable

Treatment Algorithm

1. Assess current gabapentin dosing

   • If suboptimal, optimize dosing first (up to 1200mg TID if tolerated)
   • If at maximum tolerated dose, proceed to next step

2. Add duloxetine

   • Start 30mg once daily for 1 week
   • Increase to 60mg once daily if tolerated
   • Monitor for nausea (most common side effect) 1

3. Reassess in 2-4 weeks

   • If pain reduced to ≤3/10: Continue treatment
   • If partial relief (pain remains ≥4/10): Consider adding another first-line agent
   • If inadequate relief (<30% reduction): Switch to alternative first-line medication 1

4. Consider combination therapy

   • Recent evidence supports combination therapy over monotherapy for neuropathic pain 1
   • Rational combinations target different pain mechanisms

Rationale for Recommendation

Duloxetine is recommended as the next medication based on:

1. Complementary mechanism of action: Adding an SNRI provides a different mechanism than the patient's current medications 1

2. Dual benefit for pain and anxiety: Duloxetine has shown efficacy in treating both neuropathic pain and anxiety disorders 1

3. Guideline recommendations: Current guidelines recommend SNRIs as first-line agents for neuropathic pain 1, 4

4. Safety profile: Duloxetine has fewer anticholinergic and cardiac side effects compared to TCAs 1

5. Once-daily dosing: Simpler regimen may improve adherence 1

Important Considerations

• Avoid opioid escalation: CDC and other guidelines recommend against using opioids as default treatments for chronic pain 4

• Monitor for drug interactions: Particularly between tramadol and duloxetine (both affect serotonin)

• Physical therapy: Continue to emphasize active interventions like supervised exercise 4

• Psychological support: Address anxiety component through appropriate referrals if medication alone is insufficient

• Reassessment timeline: Evaluate response to treatment within 2-4 weeks to determine next steps

By adding duloxetine to the current regimen, there is a good chance of improving both pain control and anxiety symptoms in this patient with lumbosacral radiculopathy.