It's not surprising that he charges his cage door when you open it. Right now he needs to seek out females and gather a harem. His drive is very powerful. He should be allowed to wander.
This time of year is breeding season, so his behavior is timely. If this is what's happening, it will last for one to four months, then he will return to normal. Captive iguanas' breeding seasons are more erratic than wild iguanas' seasons. There is no medical treatment that can stop this behavior, not even being neutered.
I hope you can wait him out, for his sake. No one wants to take in an aggressive iguana, so you are his only hope for a good future.