I think everyone on here is right, it is breeding season. Lest you think that "Oh, that's fine for everyone to say, but they don't know what MY iguana is like!" let me assure you that we have seen the best and worst of iguanas.
My iguana, Bud, is about 3 years old. Most of the year, he is so docile that he will come over to me and lie on my chest while I'm watching TV, and then he'll fall asleep. Right now, I can not even take him out of his cage except to take him to go potty once a day. He is just too violent!
When in the cage, he thrashes against the cage trying to attack me (He does not attack males, but unfortunately I am female!) and has bitten me, tailwhip, and scratched. When OUT of the cage, he chases me around and tries to mate with my foot, hand or neck!! My mom thinks it's funny, but let me tell you it's not. I can't take my eye off of him for a second. He has NEVER done these things before this breeding season, he was my little baby!
I just really want you to know that he is far, far better off having a home with you where he has to stay in the cage (while he is too violent) is far, far better than going to a shelter with an uncertain future. Your iguana does not mind that you can't handle him much right now. Reptiles really do not need or want human contact all that much, and you should not feel guilty about caging him when the issue is his and your safety.
It will be over soon! Even now, my iguana is behaving a little better every day. He has even remembered his potty training again- it used to be like clockwork, but lately he is just going whenever and wherever, not how he's been trained.
Post and tell us if he's behaving better soon!