There are various conditions that can cause swollen itchy eyelids, though fortunately most of them can be easily treated. One of the most common causes is a stye, which is an inflamed bump on the eyelid. Blepharitis is another possible cause, which is usually marked by swelling, redness, itchiness, and sometimes crust or ulcers. An eye allergy also often results in itchy, swollen eyelids, and can be caused by anything from makeup to different types of medical ointment.
A stye can appear suddenly in one eye, showing up as a small red bump on the lower or upper eyelid, often right where the lashes are. It typically looks like a pimple, and can cause the entire lid to look inflamed and feel itchy. The cause of this condition is usually an infected oil gland that is attached to an eyelash follicle, with staphylococcus typically being the bacteria that leads to the swollen itchy eyelids. Though the stye usually heals within about a week without any treatment, recovery can be faster when a warm compress is placed over it for a few minutes several times a day, which will cause it to drain faster and feel less tender. Patients may be tempted to pop or pick at the stye, but this can make it worse and could even cause the infection to spread to the other eye, so it is not recommended.
Blepharitis is typically caused by bacteria, the herpes virus, or an allergy. It usually presents as a red, swollen eyelid that itches and burns, and is sometimes accompanied by scales, ulcers, or crust. The treatment depends on the cause, so it is usually best to see an eye doctor in order to determine why the swollen itchy eyelids occurred. If the cause is a virus, antiviral medications may be given by mouth, while antibiotic ointment is usually offered when the cause is bacteria. Topical corticosteroids are usually necessary if the condition is caused by an eye allergy.
Some people discover they are allergic to certain substances only when their eyes swell up and become red and itchy. Many women find that this occurs after using a new makeup product, as they may be allergic to an ingredient, such as preservatives. Some antibiotic ointments used for medical treatment may also harm the eye if they get near it, while contact lens solution sometimes causes the same issue, depending on the ingredients. In most cases, patients can treat their swollen itchy eyelids by discontinuing use of the product and applying corticosteroids or taking antihistamines to relieve the swelling.