How many mg of melatonin does the product contain?

I am a bit puzzled by the answer from SKIN1004 OFFICIAL that "it does NOT contain any melatonin" as it is listed in the ingredients posted by the seller and any promo materials I have seen on the internet. As to how much - I have not been able to find the amount listed anywhere so far...

Can this be used with retin A at night?

I have been using with my prescription tretinoin and it actually helps with the dryness... I do not see any ingredients that would make it incompatible although I am not a dermatologist. If you are concerned perhaps check with your doctor.

How often should you use this?

Hello, for good a result, I would recommend you to use the product twice a day, in the morning and night. Hope you find this helpful. :)

What are the full list of ingredients?

Here is the full list of ingredients ! Centella Asiatica Leaf Water(39%), Water, Butylene Glycol, Glycerin, 1,2-Hexanediol, Niacinamide, Polyglutamic Acid, Pantolactone, Hibiscus Esculentus Fruit Extract, Carbomer, Panthenol, Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Cetearyl Olivate, Methylpropanediol, Arginine, Pullulan, Sorbitan Olivate, Caprylic/Capric Triglyceride, Pyrus Communis (Pear) Fruit Extract, Adenosine, Rosa Damascena Flower Water, Cucumis Melo (Melon) Fruit Extract, Iris Florentina Root Extract, Ethylhexylglycerin, Hedera Helix (Ivy) Leaf/Stem Extract, Sodium Phytate, Xanthan Gum, Maltodextrin, Artemisia Princeps Leaf Extract, Hydrolyzed Gardenia Florida Extract, Melatonin, Illicium Verum (Anise) Fruit Extract, Larix Sibirica Wood Extract, Quercus Mongolica Leaf Extract, Persicaria Hydropiper Extract, Rheum Palmatum Root/Stalk Extract, Asarum Sieboldii Root Extract, Chrysanthellum Indicum Extract, Corydalis Turtschaninovii Root Extract, Coptis Japonica Root Extract, Machilus Thunbergii Bark Extract, Pentylene Glycol, Hydrogenated Lecithin, Ceramide NP