Contact lens is a kind of contact lens, the current market can be roughly divided into natural enlargement of the pupil and exaggerated color category. But long-term wear contacts more harmful, if there are eye diseases, colds, fever, or minors, menstruation and pregnancy women, swimming, long-distance riding, etc. Try to avoid wearing. 1, eye disease: dry eye patients are not suitable for contact lenses or contacts, inappropriate use of contacts can also cause dry eye. Contact lenses usually lead to a decrease in oxygen permeability, and the area of the cornea covered by the pupil lens is a little larger than ordinary contact eyes, so the degree of corneal oxygen permeability is poor. Corneal oxygen deprivation which in turn promotes inflammation can lead to decreased tear film stability and promote dry eye. In addition, when conjunctivitis, keratitis, trachoma and other eye diseases are not recommended to wear contact lenses, so as not to further aggravate eye infections; 2, colds, fever: colds, fever when the body’s resistance to decline, and the hands will be with a large number of germs, in the take, wear contacts easy to take viruses, bacteria into the eyes, resulting in eye infections; 3, minors: primary and secondary school students are in the growth of the development stage, the eye axis is still developing, the eye is still in the development stage, the eye axis is still in the development stage, the eye is still in the development stage, the eye is still in the development of the eye. If you wear contacts for a long time, it is easy to cause corneal hypoxia and physiological metabolism delay and other side effects, improper care will also cause corneal infections; 4, menstruation, pregnancy: female menstruation, pregnancy, due to hormone level changes, there may be elevated intraocular pressure, corneal water increase, etc., wearing contacts may cause eye discomfort; 5, swimming: it is difficult to avoid water in the eyes when swimming, it is easy to bring viruses and bacteria into the eyes when wearing contacts; 5, swimming: it is hard to avoid water in the eyes when swimming, it is easy to bring viruses and bacteria into the eyes when taking and wearing contacts. Swimming: when swimming, it is difficult to avoid water in the eyes, wearing contacts at this time may increase the chances of microbial infection in the eye, resulting in a variety of ophthalmic diseases; 6, long-distance riding: long-distance riding, air convection accelerated, which may lead to a decrease in the moisture of the contacts, the lens gradually dry and harden, resulting in eye discomfort.