Hi there. Isoretinoic acid is prescribed for Acne which is severe or large cystic ones. Now the most common side effects are - 1)esophagitis i.e burning pain in the food pipe if you do not swallow the capsule properly - so i suggest you drink a glass full of water after the tablet and do not sleep immediately after taking the tablet. 2)skin irritation - happens in some people especially if taken during day time during sun exposure . Night time should avoid those problems. 3) may cause cheilitis - small cut like wounds near the angle of the mouth or burning sensation in the tongue but generally these are rare and some vitamin B supplements will help with this. Other symptoms like thinning of hair etc. are very rare and shouldn t be a problem. Now in your case the small side effects are minor compared to the relief that you ll have from your acne and hence follow the advice and take them. Should any reactions occur ,stop and consult your dermatologist or physician. Hope this helps.