The goal of this study was to investigate whether intravenous infusion of 1000 ml 40% calcium borogluconate combined with the oral adminstration of 500 g sodium phosphate leads to a better cure rate and longer-lasting normocalcaemia and normophosphataemia than standard intravenous treatment with 500 ml calcium borogluconate in cows with parturient paresis. Forty recumbent cows with hypocalcaemia and hypophosphataemia were alternately allocated to group A or B. Cows of both groups were treated intravenously with 500 ml 40% calcium borogluconate, and cows of group B additionally received another 500 ml calcium borogluconate via slow intravenous infusion and 500 g sodium phosphate administered via an orogastric tube. Thirty-two cows stood within 8 hours after the start of treatment and 8 did not; of the 32 cows that stood, 18 belonged to group A and 14 to group B (90% of group A vs. 70% of group B; P = 0.23). Seven cows relapsed; of these and the 8 that did not respond to initial treatment, 10 stood after two standard intravenous treatments. Downer cow syndrome occurred in 5 cows, 3 of which recovered after aggressive therapy. The overall cure rate did not differ significantly between groups A and B. Twelve (60%) cows of group A and 14 (70%) cows of group B were cured after a single treatment and of the remaining 14, 11 were cured after two or more treatments. Two downer cows were euthanized and one other died of heart failure during treatment. Serum calcium concentrations during the first eight hours after the start of treatment were significantly higher in group B than in group A, and oral sodium phosphate caused a significant and lasting increase in inorganic phosphate. More cows of group B than group A were cured after a single treatment (P > 0.05). These findings, although not statistically significant, are promising and should be verified using a larger number of cows.