From the FDA Drug Label
Side Effects Metabolic side effects include hypercalcemia. The potential side effects of ergocalciferol (D2) include hypercalcemia.
- Hypercalcemia is a serious side effect that can occur with ergocalciferol (D2) use. The FDA drug label does not provide information on the safety of ergocalciferol (D2) during pregnancy, but it does mention that hypercalcemia is a potential side effect 1.
From the Research
Ergocalciferol (vitamin D2) is generally considered safe during pregnancy when taken at recommended doses, but its use should be approached with caution due to potential side effects and the availability of more effective alternatives like vitamin D3. For pregnant women, a daily intake of 600-800 IU of vitamin D is typically recommended, though some healthcare providers may suggest higher doses (1,000-2,000 IU daily) for those with deficiency 2. Side effects are rare when taken appropriately but can include nausea, vomiting, poor appetite, constipation, weakness, and weight loss. At very high doses (typically exceeding 4,000 IU daily for extended periods), more serious side effects may occur, including hypercalcemia (excessive calcium in the blood), kidney stones, and kidney damage.
Key Considerations
- Vitamin D is essential during pregnancy for maternal bone health and proper fetal skeletal development.
- It also plays important roles in immune function and may reduce pregnancy complications.
- Before starting any vitamin D supplementation during pregnancy, women should consult with their healthcare provider who can determine appropriate dosing based on individual needs and current vitamin D levels.
- Regular monitoring may be recommended if higher doses are prescribed to treat deficiency.
- The choice between vitamin D2 and D3 should consider the evidence suggesting vitamin D3 may be more potent in raising serum 25-hydroxyvitamin D levels 3, 4.
Safety and Efficacy
Studies have shown that high doses of vitamin D, up to 10,000 IU/day, are generally safe and well-tolerated, but may increase the risk of hypercalciuria and mild hypercalcemia 5, 2. The safety profile of vitamin D supplementation is similar for doses of 400,4,000, and 10,000 IU/day, with hypercalciuria occurring more frequently with higher doses 2.
Recommendation
Given the potential for side effects and the availability of more effective alternatives, pregnant women should consult with their healthcare provider to determine the best course of vitamin D supplementation for their individual needs. The provider can assess the need for supplementation, choose the most appropriate form of vitamin D, and monitor for potential side effects 6.