I bought meladerm directly from the company, its gives a good over all complexion but as far as melasma is concerned, nothing happened to them yet.
Could any one tell me of good treatment for melasma in UK?

The best treatment for melasma is HQ 4% + retin-a you can buy them separately online (4% HQ is easy to find and I prefer obagi) but tretinoin is harder to locate from reputable sources. Just make sure that the expiration date hasn't past if you buy from India or China suppliers.