I have been experiencing peripheral neuropathy (PN) following the initiation of Mounjaro/Zepbound (tirzepatide) therapy. At lower doses, I did not experience any neuropathic symptoms; however, upon titration to the 10 mg dose, I began to develop significant PN. Initially, I attributed the symptoms to my pre-existing spondylitis and continued treatment.

After several months of persistent and progressively debilitating symptoms, I undertook a structured assessment, documenting the timing, severity, associated activities, dietary intake, and concurrent medications. This process revealed a clear temporal association between the worsening of neuropathic symptoms and the administration of tirzepatide.

Discontinuation of the medication resulted in a substantial improvement in symptoms, although complete resolution was not achieved. To further investigate whether excipients or preservatives might have contributed, I trialed a compounded formulation of tirzepatide. The recurrence of identical neuropathic symptoms with the compounded version supports the conclusion that the active pharmaceutical ingredient itself was the likely cause.