Complex sentence: However, vitamin A has also been repeatedly tested and used therapeutically over several decades in larger amounts, 100,000-400,000 IU total dosage, for treatment of severe pediatric measles in areas where vitamin A deficiency may be present, in order to reduce childhood mortality.
Split into simpler sentences: However, vitamin A has also been repeatedly tested and used therapeutically over several decades in larger amounts. For example, a total dosage of 100,000-400,000 IU has been given for treatment of severe pediatric measles, in areas where vitamin A deficiency may be present, in order to reduce childhood mortality.