Hi,
No don't use the two products togetther,you may use glycolic acid cream in morning and hydroquinone cream in night.
Also don't apply these creams near eyes or any mucus membrane.
You use moisturizer and sunscreen alon with product but even that to you may use after about 10 mins after you have applied glycolic acid cream.
You can use this cream for 6-8 weeks at a stretch and then give a break of 2-4 weeks.
It depends on you skin and how is you skin reacting that for how long can it be take ...
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