do antibiotics create demon children?

My five-year-old is just getting over strep throat, and has been on an antibiotic for four days now. I thought he was cranky before he started the meds. Now I can safely say I had no idea what I was talking about. While his fever is gone, and his energy levels have returned to normal, my son has become the very definition of irritable. He is so astonishing hair-trigger with the tears and the yelling, in fact, that I am beginning to think this may be the amoxicillin talking.

Either that or I need to call this lady.

A friend of mine suggested I first try giving him some probiotics along with the antibiotics, because maybe all the bacteria-killing is getting to him. So I’m trying that but it does seem to me like a zero-sum game to be taking anti’s and pro’s at the same time. I’m not sure what “biotics” are but it is interesting that they can be considered both bad and good for you, kind of like how “flammable” and “inflammable” mean the same thing.

And I’m not sure I’m right about any of this, since all my Googling of “antibiotics” and “irritable child” have only turned up lots of pages on irritable bowel syndrome. I would say, right about now, that my son’s bowel is the least irritable thing about him.

Have any of you ever noticed your child being extra-cranky while on antibiotics?