Cataracts - Causes

Radiation Treatments. Cataracts are common side effects of total body radiation treatments, which are administered for certain cancers.

Electromagnetic Waves. Questions have been raised about the hazards of low-level radiation from computer screens. To date, no study has demonstrated an association between cataract development and video display terminals. It is a good idea, in any case, to sit at least a foot away from the front of a screen.

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Smoking

Cataracts are one of the many ill effects caused by smoking. Many studies have implicated smoking in the development of nuclear cataracts. The major damaging effects of cigarette smoke appear to be enhancement of free-oxygen radicals, the chemical byproducts in the body that can damage cells, including those in the eye.

Medications

Corticosteroids. Long-term use of oral steroids is a well-known cause of cataracts. Studies have been conflicting, however, over whether inhaled and nasal-spray steroids increase the risk for cataracts. Information on cataract risk from inhaled steroids is important because they are commonly used by asthma patients, and steroid sprays use is increasing among allergy sufferers. Studies have suggested a higher risk for cataracts among middle-aged and elderly patients treated with beclomethasone (Beclovent, Vanceril). However, newer inhaled steroids are available and their effects on the eye are unclear. In children, cataracts are rare, and the benefits of inhaled steroids for asthma far outweigh any small additional risk.

Other Medications Associated with Cataracts.

Psoralens, a class of drugs used along with light therapy to treat skin disorders, such as psoriasis
Antipsychotic medications such as chlorpromazine (Thorazine)
Glaucoma medications

Many others drugs have been weakly associated with cataracts including allopurinol, tamoxifen, amiodarone, tricyclic antidepressants, potassium-sparing diuretics (but not other diuretics), thyroid hormone, tetracyclines, sulfamidase, and mepacrine.

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Glaucoma and Other Eye Conditions

Glaucoma. Glaucoma and its treatments, including certain drugs (notably miotics) and filtering surgery, pose a high risk for cataracts. The glaucoma drugs posing a particular risk for cataracts including demecarium (Humorsol), isoflurophate (Floropryl), and echothiophate (Phospholine).

Uveitis. Uveitis is chronic inflammation in the eye, which is often caused by an autoimmune disease or response. Often the cause is unknown. It is a rare condition that carries a high risk for cataracts.