Conjunctivitis is inflammation of the conjunctiva (a mucous membrane that envelops the eye) usually caused by a virus or bacteria, although it can also be caused by an allergy, in which case it is called allergic conjunctivitis. Agents such as dust, mould, pollen or certain chemicals are the most frequent cause of this inflammation. Conjunctivitis is contagious and spreads through the sharing of garments that have been used by the patient (such as towels). The most frequent symptoms are red eyes with greater sensitivity to light, tearing, itching, the sensation of having something in the eye and rheum. It is advisable to not wear make-up for a few days, to not wear contact lenses, wipe the eyes with cold compresses to relieve discomfort and apply the medication prescribed by the doctor. Generally, the treatment includes eye drops and drops with corticosteroids, in the case of allergic conjunctivitis, and antibiotics in the other cases.