I know it is very possiable while on the pill wondering if it's the same with the iud

An IUD is internal, not a drug, therefore it will not be effected by antibiotics.

The pill is a drug, ingested, and yes, antibiotics can cause it to be less effective.

Here's some info on how a IUD actually works there are two different types. I found this info on the internet;

Copper IUDs prevent sperm from being able to go into the egg by immobilizing the sperm on the way to the fallopian tubes. If an egg does become fertilized, implantation on the wall of the uterus is prevented because copper changes the lining of the uterus. found on the internet.

And

hormonal IUDs, a small amount of progestin or a similar hormone is released into the uterus. These hormones thicken cervical mucus and make it difficult for sperm to enter the cervix. Hormonal IUDs also slow down the growth of the uterine lining, making it inhospitable for fertilized eggs.

If you have the hormonal IUD then yes, the progestin can be effected by antibiotics but the IUD is still in place and should help prevent pregnancy.

If you're uncertain then use a condom until you are done with the antibiotics.