TREATMENT OF DIALYSIS-INDUCED HYPOTENSION WITH L-THREO-3,4-DIHYDROXYPHENYLSERINE

L-threo-3,4-dihydroxyphenylserine (L-DOPS), a precursor of noradrenali ne (norepinephrine), which is converted into noradrenaline when orally administered, was given orally to haemodialysed patients exhibiting d ialysis-induced hypotension. In five patients given 300 mg L-DOPS plas ma concentrations reached a peak of 1.43 +/- 0.59 mug/ml 6h after admi nistration and decreased slowly to disappear after 36 h. Plasma noradr enaline concentrations showed a significant increase (P<0.05), reachin g a peak of 1.28 +/- 0.64 ng/ml after 24 h and declined to 0.75 +/- 0. 47 ng/ml by 48 h. Administration of L-DOPS to six patients during dial ysis for 6 consecutive weeks showed no accumulation in the blood. Oral administration of 200 400 mg L-DOPS to 34 patients 1 h before dialysi s prevented dialysis-induced hypotension and decreased the number of c oncurrent treatments required for hypotension. The signs and symptoms of hypotension were improved in 73.5% of the patients and persisted af ter dialysis in 64.7%. The preventive effect of L-DOPS was significant ly more prominent in patients with predialysis systolic blood pressure less than 100 mmHg and in patients with non-diabetic nephropathy. L-D OPS appeared to be an effective and well-tolerated treatment for the p revention of dialysis-induced hypotension.