Hope everything has turned out well for your son. If 200mg ketaconazole is not enough, you may have to increase it to 400mg per day. This is what I did and it cured me. Whenever I get another flare up (due to antibios) I go back to the protocol: 1. 400 mg nizoral tablets 2. polybac8 probiotics 3. strict anti-candida diet (no sugars, fruit, gluten, wheat, dairy, alcohol, coffee, chocolate, fried junk food, etc). It's hard, but worth it.
After a few weeks, you should real improvement. But you need to stick to the protocol for at least 6 weeks. No Cheating. It's the only way to kill off the excess yeast, and make sure it stays off. Also, try never to use antibios - I'm hoping never to use them again!