Plasma concentrations of lidocaine resulting from instillation of lidocaine jelly into genitourinary tract prior to cystoscopy

Plasma concentrations of lidocaine were measured over a period of three hours following the instillation of lidocaine jelly (Xylocaine 2 % Jelly) into the genitourinary tract of 30 patients (15 male, 15 female) scheduled for cystoscopy. The mean quantity of jelly instilled was 21.4 Gm (11–27.5 Gm) and of lidocaine HCl administered thereby 428 mg (218–550 mg). Plasma concentration reached measurable levels in only 5 cases, never exceeding 0.2 μg/ml.