Please recommend the best foundation for severe acne?

Get serous about Rx: If you have severe acne, you need to be under the care of a competent dermatologist and if offered isotretinoin, accept it. The choice of make-up isn't going to be the key to managing what is, especially nowadays, a very serious health problem. It's possible that the oral contraceptive pill or spironolactone could clear you, or another rx. Best wishes.