Biotin can be taken with other vitamins. It is necessary for the metabolism of Vitamin PP, Vitamin B5, folic acid, and Vitamin B12, as well as for the synthesis of ascorbic acid. However, there is one notable interaction: biotin can interfere with certain lab tests, including those for thyroid function, so it's generally recommended to let your healthcare provider know if you are taking a biotin supplement, especially if you're getting blood tests.