Can I give Vitamin B12 (1500 mcg daily) and Pregabalin (at bedtime) for 2 weeks to a patient with levofloxacin-induced burning feet, who has normal sensory and neurological test results?

Management of Levofloxacin-Induced Burning Feet Syndrome

Pregabalin at bedtime (75-150mg) and vitamin B12 (1500 mcg daily) for 2 weeks is an appropriate treatment approach for levofloxacin-induced burning feet with normal sensory testing. 1, 2

Understanding Levofloxacin-Induced Neuropathy

Levofloxacin can cause peripheral neuropathy as a recognized adverse effect, which may manifest as burning feet syndrome. According to the FDA drug label, fluoroquinolones including levofloxacin can cause "sensory or sensorimotor axonal polyneuropathy affecting small and/or large axons resulting in paresthesias, hypoesthesias, dysesthesias and weakness." 3

Key points about this condition:

• Symptoms may occur soon after initiation of levofloxacin
• May be irreversible in some cases
• Should be addressed promptly to prevent progression

Treatment Approach

First-Line Medication: Pregabalin

Pregabalin is recommended as a first-line treatment for neuropathic pain according to multiple guidelines 1:

• Starting dose: 75mg at bedtime
• Can be titrated up to 150mg if needed
• Advantages:
  • Calcium channel α2-δ ligand that reduces neurotransmitter release
  • Well-established efficacy for neuropathic pain
  • Bedtime dosing helps with sleep disturbances often associated with neuropathic pain

Adjunctive Therapy: Vitamin B12

Vitamin B12 supplementation (1500 mcg daily) is a reasonable adjunctive treatment:

• May help with nerve repair mechanisms
• Studies show combination therapy of pregabalin with methylcobalamin (B12) significantly reduces neuropathic pain 2
• Low risk of adverse effects even at high doses

Evidence Supporting This Approach

1. The Mayo Clinic Proceedings guidelines specifically recommend pregabalin as a first-line medication for neuropathic pain with a starting dose of "50 mg 3 times daily or 75 mg twice daily" 1

2. A clinical study demonstrated that sustained-release pregabalin with methylcobalamin (1500 mcg) significantly reduced neuropathic pain with a 72.3% reduction in pain scores over 14 days 2

3. The FDA drug label for levofloxacin clearly identifies peripheral neuropathy as a recognized adverse effect that requires prompt intervention 3

Monitoring and Follow-up

Monitor for:

• Pain reduction using a visual analog scale
• Improvement in burning sensation
• Potential side effects of pregabalin:
  • Dizziness (most common)
  • Sedation
  • Peripheral edema

If no improvement is seen after 2 weeks:

• Consider increasing pregabalin dose (up to 600 mg/day)
• Consider adding duloxetine as an alternative first-line agent
• Refer to neurology if symptoms persist or worsen

Precautions and Considerations

1. Discontinue levofloxacin immediately if not already done, as continued exposure may worsen neuropathy 3

2. Dosage adjustment for pregabalin may be needed in patients with renal impairment 1

3. Monitor for side effects of pregabalin, particularly dizziness and sedation, which can be minimized by starting at a lower dose and titrating gradually 1

4. Reassess in 2 weeks to determine if treatment is effective or if alternative approaches are needed

5. Normal sensory testing suggests early or mild neuropathy, which may have a better prognosis with prompt treatment

Alternative Approaches If Initial Treatment Fails

If the initial treatment is ineffective after 2 weeks:

• Consider duloxetine (30-60 mg daily)
• Consider tricyclic antidepressants (nortriptyline or desipramine)
• Topical agents may be helpful for localized symptoms
• Referral to neurology or pain management specialist

By implementing this treatment approach promptly, you can potentially prevent progression of the neuropathy and provide symptomatic relief for the patient's burning feet syndrome.