Have you tried Silver Nitrate available at drug stores as caustic pencil?
What colour is his wart? If it's almost black and oozing I would advise consulting dermatologist in case it's melanoma.
Hope it helps.
Alla Cranham, MSc ABMT,
Registered Homotoxicologist
Mercury House
Northgate
Nottingham
NG7 7FN
Tel +44(0) 845 450 7316
Mob +44(0) 77361 47458
Fax +44(0) 115 9163109
http://www.in-vivo-health.co.uk