A 2 years old child without fever develops bone pain, vomiting, and features of increased intracranial pressure following excessive meditation. The drug most likely to be responsible for this is;

Vitamin A is stored in the liver, deficiency symptoms appear only after long-term deprivation, but vit A deficiency is quite prevalent, especially among infants and children in developing countries. Manifestations are • Xerosis (dryness) of the eye, 'Bitot's spots', keratomalacia (softening of the cornea), corneal opacities, night blindness (nyctalopia) progressing to total blindness. • Dry and rough skin with papules (Phrynoderma), hyperkeratinization, atrophy of sweat glands. • Keratinization of bronchopulmonary epithelium increased susceptibility to infection. • Unhealthy gastrointestinal mucosa, diarrhoea. • Increased tendency to urinary stone formation due to the shedding of ureteric epithelial lining which acts as a nidus. • Sterility due to faulty spermatogenesis, etc