This pilot study evaluates the occurrence of chlorhexidine gluconate exposure-induced skin reaction among health care workers in Thailand. From May 1-10, 2011, a 4% aqueous-based chlorhexidine gluconate solution was applied to the forearm of workers. Skin reaction was monitored from days 1-7 according to a validated grading system. For workers who developed skin reaction from the 4% solution, a 2% aqueous solution was applied to the other forearm after the original reaction was resolved. In total, 5% of workers developed a grade 1 skin reaction on the first forearm following exposure to 4% chlorhexidine gluconate. Median time to rash onset was 1 day (range, 0-3 days); no severe reactions were associated with the rash. Grade 1 skin reactions were detected in all 5 workers on whom the 2% chlorhexidine gluconate solution was applied. Median time to rash onset was 1 day (range, 0-2 days); there were no sever reactions associated with the rash. The majority of workers who developed a rash had underlying diseases, e.g., dermatitis or allergy to dust. The authors concluded that these findings highlight the need to monitor worker skin reaction to hand hygiene and antiseptic products in Asian populations, particularly those patients who have underlying diseases.