OBJECTIVE: To ascertain the frequency of correction of vitamin D deficiency (VDD) with single or multiple doses of oral (p.o.) and intramuscular (i.m.) administration of 2 high-dose preparations of vitamin D3 (VD3).
METHODS: This was a prospective intervention study conducted in an ambulatory care setting. One hundred participants with VDD (25-hydroxy vitamin D [25-OHD] <20 ng/mL) were randomized to receive a dose of 600,000 or 200,000 IU of VD3 via a p.o. or i.m. route. The main outcome measure was serum 25-OHD levels at 2, 4, and 6 months after the intervention. The same dose was repeated in participants if 25-OHD remained <30 ng/mL at 2 and 4 months.
RESULTS: At 2 months, VDD was corrected in 93.8% of participants in Group 1 (600,000 IU i.m.); 83.3% in Group 2 (600,000 IU p.o.), 87.5% in Group 3 (200,000 IU i.m.), and 70.6% in Group 4 (200,000 IU p.o.). The mean changes from baseline in vitamin D levels at 2 months were 29.6 ± 13.7, 19.8 ± 12.3, 18.3 ± 10.6, and 13.7 ± 7.8 ng/mL in Groups 1, 2, 3, and 4, respectively. The mean levels remained significantly higher from baseline in all groups at all time points during the 6 months of observation. The mean 25-OHD level achieved in Group 1 was significantly higher than all other groups at 6 months.
CONCLUSION: Two months after the intervention, VDD was corrected in more than 70% of participants with a single dose of either 600,000 or 200,000 IU given p.o. or i.m.