I don't live in the USA, but there isn't such a drug in my country that a child of that age could take.

Warts are caused by a virus and would probably respond to antiviral medications such as those used for shingles etc, but I certainly wouldn't recommend such a strong medication for such a tiny tot.

My nephew (aged 5) also has this problem. He must have had around 30 or 40 on his body and they were recently frozen off using dry ice. Unfortunately this is a painful procedure so they had to give him an anaesthetic or he'd never have tolerated the pain. I can vouch for how much they hurt as I had just one frozen off my thigh last month, and I was almost in tears with the pain, and I'm an adult!

I think it's probably best to just wait and see if they respond to the treatment that your doctor suggested, meanwhile hoping that they don't continue to spread.

We do have a medication forum here at NeuroTalk so you could also ask your question over there if you wish, and hopefully get some feedback from our resident medication specialist. Here's the link to that forum: http://neurotalk.psychcentral.com/forum72.html