A book I liked is:
"Secrets of the Baby Whisperer- how to calm,connect,and communicate with your baby" by Tracy Hogg.
There are sooooo many different thoughts on this.... you will get lots of opinions here.
I'm surprised the Doctor gave him baby Zantac and let him cry it out. Because, what you have is a "normal" baby, who is waking, who is crying, who is not sleeping through the night, and is only 4 months old. He is completely normal, and ALL Parents go through this.
I know you want the best, but try not over-analyzing it too much... you can NEVER coddle a baby too much, you can NEVER comfort a baby too much. And in fact, conversely, there are also "problems" a baby/child can get from "not" getting enough attention and/or comforting. I once baby-sat a baby like that... and it cannot always be overcome. It was sad. But the Mom did not want her baby to get "dependent" or "needy." But what actually happened is her baby was just never really happy and it affected her development, and she became less responsive to "attention" given her.
If a baby is not responded too and left to cry it out- it actually changes their brain chemistry. And, in the opposite extreme...if a baby is not comforted and not nurtured, "attachment disorders" can arise.. .meaning, the baby will not 'bond' properly and it causes behavioral problems as they get older. They NEED to bond and get comforting from the day they are born... it is crucial for their development. A baby this age is just "reacting" for survival... they don't do it on purpose to 'irk' their Parents for attention. They are merely crying for something they need, and if not getting it, will be an unhappy baby & child.
Each baby is different... at this age, they will not "sleep through the night." And, at "growth spurt" periods and developmental changes, a baby/child WILL wake more... because they need more intake and they get hungrier and need to be fed more frequently. Many times, if a baby is hungry they will be fussier and wake more, until satisfied and fed. It's normal.
Bear in mind, that it is often COMMON... that a child/baby will NOT sleep through the night, even until about 2 years old. And then by this age, other "age phases" will crop up.... and developmentally, it is hard for them too. Sleep patterns are NOT static, they always change, and we have to be flexible with them because they are developing as they should.
Sure, you want a child to have good sleep habits...but this is something that is gradual, and will not occur over night. He is too young for "sleep training" and rigid methods. He's a newborn. I really am surprised your Pediatrician has allowed the crying it out at his age.
Anyway... please don't expect sooo much from your baby. He is ONLY 4 months old... if this is what is expected of him at this age, then what about when he is 8 months old or 1 yr. old?
ALL babies will sleep "through the night" when they are ready. To "sleep train" a baby now at only 4 months old is too early. Just my opinion.
"Sleeping through the night" for a baby, means sleeping at least 6 hours of more. This is not according to "adult" standards. So, for example, if you put your baby to bed at say 7:00p.m., then 6 hours later it would be 1:00a.m. That is the middle of the night for us, but not for them.
When babies wake this much, you need to feed him. Babies, up until 1 years old, need to be fed on demand. And at growth spurts they will need more and more often. A baby cannot be fed according to the clock...they need it when they need it, by their hunger. Not ours.
Crying it out will NOT work with all babies.
Each Mom is different... and do what you feel is best. No baby can be spoiled by attention or loving.
All the best,
Susan