Fig. 2
From: A method of diamorphine (heroin) administration for harm reduction
A Solution pH of ascorbic or citric acid in saline. B βindex for a 5 s infusion rate for ascorbic or citric acid mixed with a 100 mg dose of heroin base. The βindex is a ratio of the excess mEq of [H+] added by the acid and the buffer capacity of the blood. βindex > 1 suggests the induction of a clinically relevant pH shift (> 1 pH unit, increasing the risk of phlebitis). C Small needle gauges can enable small quantities of acid to be aliquoted dropwise, adapted from Tripp et al. [24]