The best thing is to check the ingredients and ensure they are free from harsh preservatives, synthetic chemicals and anything that you know you are allergic or sensitive to.  We believe that choosing genuinely natural or organic products (look for certification) will help you to avoid these harsher preservatives and synthetic chemicals.If possible, purchase a trial or sample size and do a patch test because even products with pure ingredients may contain something you are sensitive to. To perform a patch test, apply a small amount of the product to a non-inflamed area of skin in a discreet place - either behind the ear or the inside of your elbow are good places.  Then wait for 24 hours.  If you have no reaction (an itchy, raised or red area) the product is likely to be suitable for you.