A comparison of faecal blood loss caused by tenoxicam and piroxicam in normal healthy male volunteers.

Faecal blood loss arising from tenoxicam at a dose of 20 mg/day was compared to that arising from piroxicam at a dose of 20 mg/day in a double-blind, parallel comparative study in 12 healthy male volunteers. Faecal blood loss was measured for a 1-week run-in on placebo, during 4 weeks of treatment and for a 2-week post-treatment period in both groups. Plasma levels for tenoxicam and piroxicam confirmed good compliance in all subjects. Mean blood loss during the placebo run-in period was 0.35 ml/day. Mean blood loss during treatment with tenoxicam was 0.84 ml/day and with piroxicam 0.81 ml/day. There was no significant difference between these measurements. On cessation of treatment, faecal blood loss continued both in the tenoxicam group (mean 1.30 ml/day) and piroxicam group (mean 1.41 ml/day). The difference between these was not statistically significant. No significant haematological or biochemical abnormality resulted from either of the two trial drugs during the period of the study. Urinalysis and NAG/creatinine ratio also remained unaltered in both treatment groups.