We highly recommend that you do your own research before selecting a tretinoin product, we always advise to start with the weakest concentration which is the 0.025% concentration begin by incorporating tretinoin in your skincare routine as the very last product you use at night before you go to bed as tretinoin degrades in sunlight. This is why it is important for you to apply it as your very last product. Once you have applied tretinoin for 2 nights a week after 2 weeks build up to 3 nights and gradually build up from there. There are many tutorials on how to apply tretinoin, but we will also guide you to apply tretinoin correctly, so you don't experience any major irritation.