Wic formula upsets my baby?

My husband recently was put out of work due to having 2 seizures on job. So he is out for a few months at least. We have been using gerber but I noticed it gives him a belly ache and I have to give tummy drops at least once a day, he would wake throught the night and need tummy drops and have no desire to eat. So I started trying enfamil gentlease (for fussyness & gas) & he didn't have this problem, nor did he get gy or tummyachish through the day. So my question is, are doctors generally okay with giving a perscription for formula for wic? I know I can get enfamil with wic with perscription only.