Cleansing the liver can overcome a Vit A deficiency by releasing bile, which is necessary to turn beta carotene into Vit A.
Let me quote the Nutrition Almanac, by L. Dunne:
75 Acne patients who failed to respond to other forms of treatment were given 100,000 IU of vitamin A per day.
Disappearance of the lesions occured for 30 patients in 2.5 months, for another 30 in 3 months, and 10 more in 5.5 months. All could be regarded as cured at the end of 3 months.
Extremely high doses can be toxic, but the symptoms disappear once the Vitamin is withdrawn.