The objective of this study was to evaluate the effect of postpartum administration of a calcium bolus (Dietevit Flash, Néolait, Yffiniac, France), on the metabolic parameters of multiparous dairy cows. Holstein cows (n = 38) from 3 commercial dairy farms in Western France, were randomly assigned to a control group (group A) and a trial group (group B). Cows in group B received at calving 2 boluses and 2 boluses at 12–18 h after calving. The 4 boluses supplied calcium (65 g as calcium formiate and calcium propionate), magnesium (5 g), vitamin E (4,000 IU), vitamin D3 (50,000 IU) and niacin (12 g). Blood samples were taken 12 d before calving, 12 and 28 h after calving and 10 d after calving. Blood serum was then analyzed for calcium, magnesium and vitamin E at the Frank Duncombe's Lab, France. The metabolic profiles of the 2 groups were compared using repeated measures ANOVA (SPSS v18). The incidence of cows with postpartum hypocalcemia (calcium < 80mg/L) in both groups was compared using the Pearson Chi-squared test. Compared with group A, cows in group B had higher calcemia at 12 h postpartum (87.3 vs. 79.1 mg/L, P = 0.02) and 28 h postpartum (86.3 vs. 76.4 mg/L, P = 0.01), lower magnesemia at 28 h postpartum (19.0 vs. 22.1 mg/L, P = 0.03) and higher blood levels of vitamin E at 28 h postpartum (2.2 vs. 1.4 µg/L, P = 0.04). Prevalence of hypocalcaemia was significantly decreased in group B (7.1% vs. 37.5 and 25% vs. 56.2%, P = 0.01) at respectively 12 and 28 h postpartum. In conclusion, the Dietevit Flash bolus significantly improves calcemia in postpartum multiparous dairy cows. The Dietevit Flash helps secure the difficult peripartum phase by decreasing the prevalence of subclinical hypocalcaemia in a significant way during the first 2 d of lactation.