Biochemical and haematological changes induced by tienilic acid combined with propranolol in essential hypertension.

Sixteen patients with moderate essential hypertension completed a double-blind crossover trial with four treatment periods each of 6 weeks. They received in random order: placebo; tienilic acid 250 mg/day; propranolol 80 mg twice daily; and tienilic acid 250 mg/day combined with propranolol 80 mg twice daily. Average blood-pressure in the lying position was 22.6/13.1 kPa (169/98 mm Hg) on placebo; 21.0/12.5 (157/94) on tienilic aicd; 21.2/12.0 (159/90) on propranolol, and 18.9/11.5 (142/86) on tienilic acid combined with propranolol. The effects of tienilic acid and propranolol on blood-pressure were additive and there were no statistically significant interactions. Tienilic acid significantly reduced serum-urate from 0.33 to 0.18 mmol/l and induced hypokalaemia which was corrected by propranolol. Basophil count and haemoglobin were lower after tienilic acid treatment than they had been at the start of the study.