Lysine acetyl salicylic acid in acute renal pain.

The effect of repeated doses of 1.8 g lysine acetyl salicylic acid (LAS) i.v. on severe pain secondary to acute renal colic (ARC) was studied in 45 consecutive patients. Clinically acceptable analgesia was obtained in 65% of the cases. No additional pain relief was achieved with the combination of pethidine 100 mg i.v. + metoclopramide 10 mg, i.m. (narcotics). Pain relief occurred within five minutes in one third of the patients while in the rest within 30 minutes. Significant reduction of systolic blood pressure (mean +/- S.D.) 23.8 +/- 19.5, pulse rate (mean +/- S.D.) 19.5 +/- 10.1 and vomiting were noted in patients who had pain relief. The incidence of nausea has increased after LAS administration. No other side effects were observed. LAS might therefore be applied as a first-hand alternative to narcotics for the treatment of ARC.