Reflux at 8 months still

Does anyone have any experience of this?
My DS was diagnosed with silent reflux at 5 weeks. Initially on gaviscon but then switched to ranitidine.
By 12 weeks we saw improvement in his symptoms and he was a much happier baby, although if we tried to reduce the doseage the symptoms would return.

At about 5 months, he started getting regular reflux, so being sick a lot and this has continued until now.
The doseage of ranitidine is so high that the pharmacist questions us and in one case wasn't happy to give to us. We've also been back on the gaviscon the last month with no real improvement but DS had been struggling with constipation.

DS is a small baby, has dropped centiles consistently but as he "presents well" and hits milestones hv unconcerned.

GP initially said he should grow out by 4 months, then 6 months, then once he is eating solids and crawling.... We've passed all of those times without improvement.

I just don't know what to do.
The medication does not seem to be working, and he has been on it practically his whole life. I almost feel that since it isn't doing anything maybe I should stop it? I'd go back to gp but he'll just up the meds like he does every time.

Just after other experiences or advice really.