Age of baby is important. Should have been mentioned.
Anyway, treatment depends on the child's condition, like is the baby taking fluids like milk or ORS orally well, is he/she passing urine normally, active baby or drowsy??
Next Steps
You should take consultation if the baby is getting drowsy and not feeding well or is sleeping mostly.
Health Tips
Ateast give him continuous feeds every 2 hours if age less than 6 months. Continue Zinc drops, but stop cefixime, it will increase loose motions at present. Contact me if need more help.