Prick testing: Prick testing with chlorhexidine was undertaken in some patients with a positive patch test reaction to chlorhexidine. The test was performed on the forearm with chlorhexidine digluconate 0.5% aq. The reaction was read after 20 min. Normal saline and histamine 10 mg/ml served as negative and positive controls, respectively. The test was only considered to be valid when the positive control was positive and the negative control was negative. The criterion for positivity was a mean wheal diameter of ≥3 mm.
Questionnaire: In the autumn of 2014, a questionnaire was sent to all patients who had shown a positive reaction to chlorhexidine digluconate and/or chlorhexidine digluconate from 1 January 2003 to 31 December 2013. A reminder was sent to those who had not responded after 3 weeks. The questionnaire comprised six questions (Table A1). First, we asked patients whether they were aware of the cause of the allergy and of possible re-exposures after the allergy was diagnosed. Second, we asked whether patients were aware of the use of chlorhexidine in cosmetic products and in the healthcare setting. Third, we asked whether the allergy to chlorhexidine caused limitations in their everyday life.
Objective: Using HPLC to determine the Compound Camphor Cream chlorhexidine digluconate content. Methods: Kromasil - C18 (250.0mm × 4.6mm, 5μm) column with a mobile phase of methanol - water - triethylamine (44: 56: 1) (adjusted with phosphoric acid to pH 3.5 ± 0 .1), a flow rate of 1.0ml / min, the detection wavelength 258am. Results: The linear range of 0.08-0.72μg, r = 0.9999, the average recovery was 99.92%, RSD = 0.04%. Conclusion: The method is convenient, sensitive, accurate, reproducible, and you can control the quality of the drug.