I know how bad acne medicines can dry out your skin! I started and now own my own health and beauty care business and make a lot of acne care products that people are LOVING! If you want to take a peek at my products visit my store on Etsy.com. I have a lot of skin care products that help acne and also the dryness that comes with it.
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I don't suggest using anything new in correlation with your medicine. If you want a natural way to help the dryness, use honey as a facial mask and leave it on for 10-15 minutes and wash off with Luke warm water. Glycerin and aloe gel (the kind without alcohol) are good things to use to combat dryness without breaking out. I know this may sound scary because its an oil, but Castor oil is actually good because it moisturizes without clogging pores and its an antibacterial. Jojoba oil is great too because its not really an oil, but a liquid wax that mimics the sebum in our skin. There's a saying, 'dissolve like with like' meaning you can dissolve the oils (sebum production) with another product that is the same (jojoba oil). If you need anymore suggestions, let me know or contact me at my website on etsy.