Hi Nicky,
I've never had UVB myself but it seems that it is more of a temporary type of treatment, so it will give relief for a few months & then the p can come back.
The one thing that would worry me about uvb it is the risk of skin cancer :-/ and it is not recommended to be continued indefinitely.
Its more of a quick-fix type treatment - so while it can help clear the symptoms - it might not get to the root cause - as sometimes p can be triggered by something in the diet or a mineral deficiencey etc.
I have had so much help with diet/nutrition/cleansing for my skin that if you ever were looking for another treatment - I would really recommend giving it a go!!!!
Sometimes I get flare-ups but I can pretty much get myself back on track by stepping up my regime
Take care,
Jade x