I have been on Lumixyl for four months now, together with monthly Silkpeels to treat the melasma on my cheeks and upper lip. The bottom line is that it works--but slowly. When I first bought it, I was really psyched to learn about studies that showed that subjects' melasma improved by 80% at the end of 8 weeks, or whatever, but I would say, after 16 weeks, the improvement is more like 40% (so, half the rate promised). I am onto my second bottle--the first one lasted about three and a half months, using a tiny bit at a time.
Nevertheless, it works. My esthetician did some before and after photos on me about 6 weeks in and there was definite improvement--disappearance of some freckles and overall lightening of the melasma. I am not sure how much the Silkpeels are adding, but they are expensive procedures and when I reach the end of my package I might just stick to my at-home glycopeels and twice-daily application of the Lumixyl. If this melasma ever goes away on this regime, I will definitely update!
Oh, another thing. Several reviews said this also helped adult acne, but I have seen none of that, unfortunately.
I have read that taking pycnogenol supplements and Vitamin C and zinc can help with melasma too so I am doing that. Other than that, I guess my final word on this is that it is worth trying, but not to expect miracles!
Update: just to add one more thing--the packaging truly sucks! The cap that goes over the pump dispenser cracks very easily and the pump on my second bottle stopped working after just three weeks. Luckily my dermatologist's clinic replaced it without extra charge. For $100 I expect packaging that works :-(