Treatment of dialysis-induced hypotension with L-threo-3,4-dihydroxyphenylserine.

L-threo-3,4-dihydroxyphenylserine (L-DOPS), a precursor of noradrenaline (norepinephrine), which is converted into noradrenaline when orally administered, was given orally to haemodialysed patients exhibiting dialysis-induced hypotension. In five patients given 300 mg L-DOPS plasma concentrations reached a peak of 1.43 +/- 0.59 micrograms/ml 6 h after administration and decreased slowly to disappear after 36 h. Plasma noradrenaline concentrations showed a significant increase (P < 0.05), reaching 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 dialysis for 6 consecutive weeks showed no accumulation in the blood. Oral administration of 200-400 mg L-DOPS to 34 patients 1 h before dialysis prevented dialysis-induced hypotension and decreased the number of concurrent treatments required for hypotension. The signs and symptoms of hypotension were improved in 73.5% of the patients and persisted after dialysis in 64.7%. The preventive effect of L-DOPS was significantly more prominent in patients with predialysis systolic blood pressure less than 100 mmHg and in patients with non-diabetic nephropathy. L-DOPS appeared to be an effective and well-tolerated treatment for the prevention of dialysis-induced hypotension.