Usually caused by a bacterial infection, styes appear like a pimple on the outside or inside of the eyelid.

Styes are fairly common and most resolve without treatment within a few days or weeks. A warm compress may be used to encourage the stye to release pus and heal more quickly.

In blepharitis, the rims of the eyelids become inflamed, red and swollen (see picture, below).

Blepharitis can develop at any time, but is more likely in people over 40. It may be caused by a bacterial infection or be a complication of another condition such as seborrhoeic dermatitis or rosacea. Symptoms include itchy, sore eyelids, crusty eyelashes and eyelids that stick together upon waking.

Blepharitis is not usually serious, but it can be a long-term, chronic condition. There is no cure, but establishing a daily eye-cleaning routine may help to control symptoms.