Older people tend to take multiple medications, many of which list vision problems such as blurred vision as a potential side effect. These include corticosteroids such as prednisone, anti-arrhythmia drugs, erectile dysfunction drugs, and tamoxifen.
In general, these warnings are overly cautious, since effects on vision from prescription drugs are very rare. However, long-term use of certain medications may result in vision problems that merit monitoring by an eye doctor. Always consider drug side effects when visual symptoms develop, and be sure to tell your eye-care professional about all medications you are taking. Regular use of any drug associated with serious vision disorders merits periodic monitoring of the eyes.