Hello, I'm myself a General practitioner. I have had three warts on the first two digits in my right hand for more than 6months now. They have been slowly increasing in size and have become rough. Max size is 0.5mm in dia. And new minute ones have sprouted near them too. I have used salicylic acid(6%) for local application. But it hasn't made any difference. What other treatment option should i choose next? And how can I prevent further ones from appearing?