Should I feed him more?

Hes 4 months and has been drinking 4-6 oz. every 2-3 hours sinse he was 1 week old. WIC and his pediatrician said that was as much as a 6 month old should be eating. So I went to 4oz. every 3 hours or as long as he could last. Well he's hungry like every hour. Ive even given him a full bottle and he drinks the whole thing and is still hungry 2 hours later. He's never once had a sign of being full. What should I do? he also wakes every 2 hours at night. My husband says give him a full bottle. Hes over 15 lbs and 4 months already...