Can Mounjaro (tirzepatide) cause neuropathic pain in the 1st metatarsophalangeal (MTP) joint of the big toe?

Mounjaro (Tirzepatide) and Nerve Pain in the First MTP Joint

Mounjaro (tirzepatide) is not known to directly cause neuropathic pain in the first metatarsophalangeal (MTP) joint of the big toe. While diabetic peripheral neuropathy is a common complication of diabetes that can affect the feet, including the MTP joints, there is no specific evidence linking Mounjaro to localized neuropathic pain in the first MTP joint 1.

Understanding First MTP Joint Pain

First MTP joint pain can have several causes:

• Diabetic peripheral neuropathy (DPN): Can cause neuropathic pain in the feet, including the MTP joints 1
• First MTP joint osteoarthritis: Can present with neuropathic pain characteristics in approximately 31% of cases 2
• Turf toe injury: Hyperextension injury to the first MTP joint that can cause pain 3, 4
• First MTP joint instability: Can be an independent pain generator in the foot 5, 6

Diabetic Neuropathy and Medication Considerations

If you have diabetes and are experiencing pain in the first MTP joint, consider:

• Diabetic peripheral neuropathy: This is a common complication of diabetes that can cause pain, burning, tingling, or numbness in the feet 1

• Risk factors for neuropathy:

  • Hypertension is an independent risk factor for developing diabetic neuropathy 1
  • Obesity is consistently associated with neuropathy in cross-sectional and longitudinal studies 1

• Weight loss medications and neuropathy:

  • Previous trials of weight loss medications (topiramate and exenatide) showed negative results for neuropathy treatment 1
  • There is no specific evidence that Mounjaro (tirzepatide) causes or worsens neuropathic pain in the first MTP joint 1

Treatment Options for Neuropathic Pain

If you're experiencing neuropathic pain in the first MTP joint, treatment options include:

• First-line pharmacologic treatments:

  • Pregabalin or duloxetine are recommended as initial pharmacologic treatments for neuropathic pain in diabetes 1
  • Gabapentin is also supported by high-quality evidence for treating diabetic neuropathic pain 1

• Additional medication options:

  • Tricyclic antidepressants (e.g., amitriptyline) can be effective but may have anticholinergic side effects, particularly in older adults 1
  • Sodium channel blockers (lamotrigine, lacosamide, carbamazepine, oxcarbazepine, valproic acid) 1
  • Topical treatments like capsaicin patches (8%) or lidocaine patches (5%) for localized pain 1

• Avoid opioids:

  • Opioids are not recommended as first- or second-line therapy for neuropathic pain due to limited evidence of long-term efficacy and high risk of addiction 1

Special Considerations for First MTP Joint

• Proper footwear and offloading:

  • Ensure proper fitting of orthotic devices to prevent pressure sores 7
  • Consider offloading devices if there is significant pain or risk of ulceration 1

• Evaluation for other causes:

  • First MTP joint osteoarthritis can present with neuropathic pain characteristics 2
  • Consider fluoroscopically-guided local anesthetic injection to diagnose first MTP joint as a pain generator 6

When to Seek Medical Attention

Seek medical attention if:

• Pain is severe or persistent despite conservative measures 1
• There are signs of infection or ulceration 1
• Pain is accompanied by significant limitation in mobility 4
• There is visible deformity or instability of the joint 5

Prevention Strategies

• Glycemic control: Near-normal glycemic control implemented early can delay or prevent the development of diabetic peripheral neuropathy, especially in type 1 diabetes 1
• Blood pressure management: Controlling hypertension may help prevent neuropathy progression 1
• Proper footwear: Wear appropriate shoes that don't put excessive pressure on the MTP joints 7
• Regular foot examinations: Perform comprehensive foot evaluations at least annually to identify risk factors for ulcers and amputations 1

Remember that diabetic neuropathy is a diagnosis of exclusion, and other causes of neuropathic pain should be considered and treated if present 1.