There are two potential conditions going on here. The first would be blepharitis, which is an inflammation of the eyelid margin, where the eyelashes come out. This usually causes itching of the eyes as well as itching of the eyelid and there is usually a good amount of crusting drainage at the lid margin. The treatment of blepharitis is straightforward, involving daily use of warm compresses to remove the crusting material and complete avoidance of eye makeup until the condition clears up. Also in more serious cases your doctor
may prescribe a topical antibiotic ointment. The second possible condition is rash on the eyelids itself, away from the eyelid margin. This is almost always a contact dermatitis, causing redness, itching, and scaling of the skin of the eyelid. Contact dermatitis of the eyelids is almost always caused by some ingredient of a cosmetic product, and the treatment includes avoiding eye makeup and similar products. Also, a low potency steroid cream is usually used to help clear up the inflammation more quickly. The best first step is to schedule an appointment with your primary care doctor
to help determine which of the two conditions you have and to help you figure out a treatment plan.