Rx D3™ Forte contains cholecalciferol, the precursor to Vitamin D3 for all animals. The cholecalciferol is blended with MCT oil. The cholecalciferol is blended with MCT oil at a higher concentration than the standard Rx D3. This provides 5 times the potency per drop to better suit the needs of the severely vitamin D3 deficient patient, the larger patient, or any other patient that would benefit from a higher concentration. Rx D3 Forte comes with a glass graduated dropper to facilitate accurate serving size.