“…That study evaluated histamine, saline and glycerosaline reactions using two different skin picks at 15, 20 and 25 min. 11 The GREER â Pick System (GREER â ; Lenoir, NC, USA) produced reliable and well-demarcated wheals with 6 mg/mL glycerinated histamine as a positive control without creating wheals with the negative glycerosaline control. In contrast, the Duotip-test II pick â (Lincoln Diagnostics Inc.; Decatur, IL, USA) glycerinated histamine reactions were small and not significantly different from glycerosaline.…”