What is best for infant constipation?

There are several things you can do as a home remedy. But being your son is only 16 days old, DO NOT give any kind of syrup or juices in any way unless his pediatrician says its ok. His system is still adjusting to the outside world and you don't need to put it to the test with these home remedys. The best thing to do is call your pediatrician. For him to be refusing your or milk, you may have eaten something that is agitating him and he does not want to drink it. Just call you pediatrician.