Probable Harmful Interaction
Both vitamin A and isotretinoin can cause toxic symptoms if taken in excess. It is presumed likely that simultaneous use of vitamin A and isotretinoin would tend to amplify the risk. For this reason, people using isotretinoin should not take vitamin A at doses higher than the recommended daily allowance; in fact, because most people get enough vitamin A from the diet, it might be preferable to take no vitamin A supplements at all. (Supplements that use
beta-carotene
to supply vitamin A are probably safe.)