What Causes Passing Of Odourless Loose Stools In Infants?

My son is 17 months old and has been on antibiotics, ranitidine and zrytec. He has allergies and had a sinus infection. His stools have been loose (assuming from the antibiotics) but we also have noticed they are odorless. Is that okay or normal. I have never experienced that with a child. Honestly never heard of it. Thanks.