Vidalta 10 mg tablets for cats and Vidalta 15 mg tablets for cats Presentation 10 mg tablet: Round pink tablet with little spots. Each tablet contains 10 mg carbimazole as active ingredient. Colouring agent: Red ferric oxide (E172): 0.25 mg. 15 mg tablet: Round dark pink tablet with little spots. Each tablet contains 15 mg carbimazole as active ingredient. Colouring agent: Red ferric oxide (E172): 0.75 mg.