Baby constipation


Hi guys

My baby now is 6 months old and we started solid about a month ago but as soon as we started solids she started constipation. I took her to the doctor and he gave us lactose laxative and till now if I didn’t give her the laxative she get constipated. She’s breastfeeding.

When i went back to the doctor after 3 weeks her told me i should continue with the laxative for 3 more weeks.

But i am not surr what to do. Is she going to be constipated for long?