Nice question .
Actually antibiotic kill all the bacteria( harmful bacteria and beneficial ( good ) bacteria ) of human body and your body also have good bacteria to digest your food completely .
So when any antibody should take then previous prebiotic is necessary to take with antibody.
Prebiotic have good bacteria to help in your digestion.
Next Steps
You should take consultation before taking of any medicine.
Health Tips
please keep record of antibiotic treatment as duration and dose .