Localized Cutaneous Reaction to Chlorhexidine After Lumbar Trigger Point Injections: A Case Report

We describe the case of a 38-year-old patient who developed a delayed localized cutaneous hypersensitivity reaction after she underwent lumbar trigger point injections (TPIs). This patient had undergone numerous TPIs in the past without adverse reactions. Notably, she had one prior similar episode; in both episodes, a larger volume of chlorhexidine was used during skin preparation. These findings suggest that the combined effects of a longer dry time and inadvertent subcutaneous chlorhexidine exposure were the likely drivers of these reactions. This case presents a unique manifestation of chlorhexidine hypersensitivity via subcutaneous introduction.