DS has thrush - any tips?

[bumpertobumper]

DS1 who is almost 7 has what I think is thrush under his foreskin. We have been doing lots of washing (trying for twice a day but not always succeeding, no perfumed soap) and applying canesten and occasionally live natural yogurt which are what usually do the trick for me.
But he has had it for 3 weeks now so I think I should take him to the doctor but will they have any other treatment?
Any suggestions if what else we could do to get rid of it?
He has white gunk and is itchy which is what I have based my diagnosis on - could it be something else?
thanks

take him to the gp in case he needs antibiotics. I wouldn't have treated in the first place without seeing the gp. Smegma can build up under the foreskin which is quite normal but I would check out the itching.

could be balanitis

GP definitely. It needs to be tested and not self diagnosed at this age.