Supplements and/or pills that contain calcium should as a strong rule of thumb not be taken

Calcium orotate is a more than acceptable supplement where  supplemented  where vitamin K2 MK-7 and where  magnesium orotate is supplemented on basically empty stomachs.  As a strong rule of thumb however supplements and/or pills that contain calcium should not be taken.

Pantothenic acid from calcium d-pantothenate can be supplemented. Calcium in calcium d-pantothenate can be separated by pouring from a capsule calcium d-pantothenate into water. Calcium and pantothenate  are drunk immediately.

Calcium silicate should not ever be in supplements. Salt that contains calcium silicate which is iodized salt should ever not be purchased, Supplements  and/or pills that contain dicalcium phosphate should not ever be supplemented and/or taken.   

Caffeine pills that contain calcium phosphate should not ever be taken. Iron supplements that contain calcium should not ever by supplemented.  

Calcium bound to other small molecules could be antagonizing calcium-sensing receptors. Calcium-sensing receptors regulate calcium homeostases.

Calcium orotate has  has a formula of C10H6CaN4O8. Calcium orotate is around 11% calcium.