Effects of the concentration of histamine on the magnitude and duration of itch, pricking/stinging, and burning. Linear regressions for logarithmic (Lg) histamine concentrations and logarithmic (Lg) values of the mean peak magnitude (“Lg peak mag”), duration (“Lg duration” in minutes, m), and AUC (Lg AUC) for itch (A, B, and C, respectively), pricking/stinging (D, E, and F), and burning. With the exception of the duration of burning, the slope of each line was significantly different from zero (see main text).