Transient paresthesia following polymyxin B loading dose in a critically ill patient: a case report

Background: Polymyxins, including colistin and polymyxin B, are considered salvage therapy to treat infections caused by multidrug-resistant gram-negative bacteria. Despite their importance, the clinical use of polymyxins is often constrained by their narrow therapeutic index, especially due to nephrotoxicity and neurotoxicity. Paresthesia associated with polymyxin B is often underreported, not fully understood, and only a few cases highlight this. Case presentation: We present a case of transient paresthesia occurring shortly after the administration of a loading dose of polymyxin B in a critically ill 33-year-old South Asian woman with intra-abdominal sepsis. Interestingly, the symptoms resolved spontaneously despite the continuation of the maintenance regimen. Conclusion: This case highlights the under-recognized neurotoxic potential of polymyxin B, particularly during loading doses, and underscores the importance of vigilance and individualized clinical judgment when balancing antimicrobial efficacy with tolerability.