Is baby having this frequency since birth or only for few days Baby had diarrhoea, just give breastfed frequently, urine output should be normal. As baby is small kindly go for physical consultation, and use coconut oil or rashfree ointment for diaper rash, no need for hydroxyzine drops. Cry might be due to rash.
Next Steps
Physical consultation is must, stool analysis, and stool for reducing substance t/r/o primary lactase deficiency
Health Tips
Coconut oil application before using diaper