Thank you for your query,
My answer to your question may be late but i think it will be appropriate for your child problem.
Your child is above the 97th percentile on CDC growth charts according to his age and he is obese
Is he exclusively breast fed or bottle fed? As bottle feeding is associated with overfeeding leading to obesity in children.
Is there any familia childhood obesity? Organis causes of obesity to be ruled out like genetical, hypothyroidism
and cushing syndrome by appropriate investigations as these are treatable conditions with medications.
Diet should be balanced, without any junk food, cakes,sweets. Consult a dietician for his diet plan
Physical exercises appropriate for his age to be introduced.
For G6PD take precautions while giving medication and get the list of avoiding medication from your doctor.
Hope I have answered your query.