In a multicentre prospective study, 261 patients undergoing transurethral resection of the prostate (TURP) in 17 urology departments were randomised to receive lubricating jelly containing either 3% tetracaine hydrochloride, 1% lignocaine hydrochloride, or no local anaesthetic. No patient had a history of urethral instrumentation or a previous urethral stricture. After 6 months' follow-up, 25/79 patients (32%) treated with 3% tetracaine jelly developed urethral strictures, as did 4/92 patients (4%) who received 1% lignocaine and 2/90 (2%) who received the jelly without anaesthetic. It was concluded that the use of 3% tetracaine jelly is associated with a high incidence of post-TURP urethral strictures.