Using a beard roller is safe and virtually without side effects if you stick to the needle size from 0.25 to 0.75 mmwhich is the correct recommendation for home use. Anything above this size could create side effects as the needles begin to pierce deeper and deeper. It is also recommended that people with psoriasis or eczema avoid microneedling in most cases. You should also always disinfect the roller before and after each use to minimize the risk of infection. Here are some of the known side effects: Bleeding Bruises Infection Worsening of acne Skin peeling Formation of scar tissue At first, you may notice some skin irritation - redness and inflammation - but these side effects should disappear after a few days. You may also experience minor bleeding. If the bleeding is excessive, you may be pressing the roller too firmly against your skin. Remember to disinfect needles before and after use!