6 week old refuses to feed

My six week old started experiencing acid reflux at 2 weeks.  He was fighting me at every feeding.  He was put on Zantac, which made no difference.  He was recently put on Prevacid, but no difference either.  I try to hold him upright during feeding, but that seemed to make no difference either. I even got the nap nanny to help him sleep better.  The feeding symptoms got worse and worse, until 2 days ago he refuses to eat at all when he's awake.  I can only get him to nurse a tiny bit during his sleep or by letting him suck on a pacifier first and taking it away.  But that only works once or twice a day.  I hold him all day, hoping to catch him while he's calm and ready to feed.  But as soon as he is awake and as soon as I try to get him near my breasts, he will cry.  Has anyone else experienced this and offer suggestions?  The pediatrician just keeps on increasing the dose of the medication, but I'm very worried in the meanwhile.