Background Low levels of serum 25-hydroxy vitamin D are associated with increased arterial stiffness and hypertension. Supplementation with vitamin D precursors has been proposed as a treatment option for these conditions. We examined the effect of oral cholecalciferol on arterial stiffness and blood pressure in healthy normotensive adults. Methods 40 healthy adults were randomised in this double-blinded study to either oral cholecalciferol 3000 IU/day or matching placebo and were followed for 16 weeks to examine any effects on pulse wave velocity (PWV), augmentation index (AIx), peripheral and central blood pressure and 24-hour ambulatory blood pressure. Results 22 subjects in the cholecalciferol arm and 18 subjects in the placebo arm completed the 16 weeks of follow-up. There was no difference in changes in PWV, AIx corrected for heart rate or central or peripheral blood pressure between the two groups. There was no correlation between serum 25-hydroxy vitamin D and any of these parameters. Conclusions Oral cholecalciferol 3000 IU/day does not affect arterial stiffness or blood pressure after 16 weeks of treatment in healthy normotensive adults. Trial Registration ClinicalTrials.gov NCT00952562

Levothyroxine ( LT ), T4, poisoning is rarely associated with a severe outcome. However, cases with significant complications have been reported. The aim of this study was to identify factors associated with symptoms of poisoning including late‐onset symptoms. All enquiries to the Danish Poison Information Centre ( DPIC ) concerning LT poisoning between March 2007 and September 2012 were reviewed and the following parameters were recorded: age, dose, time from ingestion, multiple drug intake and symptoms. To evaluate the frequency of late‐onset symptoms, a subgroup of patients without initial symptoms were contacted. A total of 181 patients were registered (112 children). Ingested LT dose ranged from 10 to 9000 mcg (median 275 mcg). A total of 29 of 181 (16%) patients were symptomatic at the time of enquiry, and there was no difference in ingested LT dose between asymptomatic and symptomatic patients, neither in children nor in adults (age 16–92 years) ( p < 0.68 and p < 0.47, respectively). In total, 153 of 181 (85%) patients did not have symptoms of poisoning at the time of enquiry; however, in 9 of 21 (43%) patients, we were able to contact, late‐onset symptoms existed. In none of the cases, hospital contact was needed and there were no reports of long‐term sequelae. Acute LT poisoning often follows a benign course. The occurrence of symptoms appears not to be dose dependent. Late‐onset symptoms seem to be common. However, all symptoms resolved spontaneously without need of medical care.

Background: Vitamin D repletion with high doses of vitamin D is often recommended to patients and healthy subjects. The safety, especially concerning changes in urinary calcium excretion is of great importance.Methods: In a double-blinded, placebo-controlled study in 40 healthy volunteers, we examined the changes in mineral metabolism during supplementation with 3000 IU of oral cholecalciferol daily during 4 months.Results: Both 25(OH)vitamin D and 1,25(OH)(2)vitamin D increased significantly in the active treated group as compared to the placebo group (186% versus 14% (P < 0.001) and 28% versus - 8% (P < 0.001)). No change was observed in urinary calcium excretion in the active group compared to the placebo group (P = 0.891). Fibroblast growth factor 23 increased significantly by 10% (P < 0.018) in the active group. However, there was no difference in changes in FGF23 between treatment groups (P = 0.457).Conclusion: High dose cholecalciferol significantly increases 25(OH)vitamin D and 1,25(OH)(2)vitamin D levels compared to placebo. No changes in urinary calcium excretion or other measured components of the mineral metabolism were found between groups.