No. Although liver enzymes often look bad on isotretinoin actual liver damage is almost unheard of.
Believe it or not. increasing hydration, a lot, is the most effective counter to isotretinoin fatigue. The explanation is long and complicated, but because of the systemic changes the drug causes. much more water is needed to metabolize energy than normal.
Also, Vitamin B12 is usually depleted for the people experiencing severe fatigue while on it, so supplementing with something like Neurobion Forte can help.