Been taking it since 2010. Use it eod. Can't say I've noticed effects that are negative. I've had more loose stools past couple months, since using it eod. Was using once or twice a week for months before this. Can't say I've noticed any negative effects.
Most studies have been done on tretinoin since nineteen fifties ,with no negative effects , from my understanding . Haven't seen much, except this thread, or any literature in tretinoin in regards to any negative effects. Isotretinoin, accutane, can cause liver enzymes elevated, kidney issues. It makes sense topical could cause this too if used in excess. I'm sure it's dose dependent.
Is Tazorac a retinal or retinoid?