Styes are caused by an infection in the hair follicle at the root of an eyelash. The infected area becomes sore and red, making blinking extremely painful. Later, a spot will form and the eyelid may itch. Rubbing the eyes must be avoided, however, because this will only increase the irritation and may spread the infection. Do not try to treat a style yourself beyond bathing it gently, using cotton wool moistened in warm water or a weak solution of boric acid. There is no truth in the old gold remedy so if you do get a stye, consult your doctor instead, who will treat it with an antiseptic ointment. Very occasionally a stye may be blind that is it develops in a gland beneath the skin and becomes blocked. This will need separate treatment, sometimes even surgery to clear it.