I always love how people get answers: Here is what Wiki says about why to get frequent eye exams and why rx’s expire.
It’s doubtful anybody knows for sure why eyeglass and contact lens prescriptions expire, or why they expire when they do. It’s likely to be due to many reasons.
One such reason that optical prescriptions expire is to ensure patients get frequent eye exams. Frequent eye exams are good for the patient. Frequent exams are also good for the profitability of an optometric practice.
But not too many years ago in the United States, many eyeglass prescriptions didn’t HAVE an expiration date. Dispensing optometrists could do eye exams nearly at cost, since they could be fairly certain of selling eyewear to their patients. But some optometrists wanted to increase the odds of an eyewear sale, and so would not give patients a copy of their prescription.
That was a problem which the Federal Government tried to remedy, first in 1978 through the Federal Trade Commission “Eyeglass Rule”, and later in 1984 through the legislature’s passage of the “Fairness to Contact Lens Consumers Act“, implemented by the F.T.C. as “The Contact Lens Rule (16 C.F.R. Part 315) and the Eyeglass Rule (16 C.F.R. Part 456).”
These rules state that an eye doctor must give every patient a copy of their prescription, even if the patient doesn’t ask for it!
That changed things. No longer could optometrists depend of the sale of glasses and contact lenses to be their profit center. They now needed charge more for eye exams, and they needed to do a lot more of them. And one way to do more exams was to have eyeglass and contact lens prescriptions expire, and to expire quickly.
However, the F.T.C. stepped in again, and issued a rule that contact lens prescriptions must be valid for AT LEASE ONE YEAR. They also stipulated that if a State law required a longer period, that longer period would be the rule. So in California, for example, eyeglass prescriptions must be valid for AT LEAST TWO YEARS.
The above is one argument as to why optical prescriptions expire after one or two year. Another argument is presented below.
Depending on the doctor eye glass prescriptions will expire anytime with in a 2 year period of time. This is for a few reasons. The doctors not only check you eyes for sight problems but also medical problems and such. For patients with certain medical conditions eye exams are a very important part of their overall medical care. Although people may find that since their vision has not changed and there is no need for an eye exam there could be issues such as cataracts, glaucoma, macular degeneration, certain types of pituitary tumors, optic nerve disorders that are picked up during routine eye exams. Most people will go for a physical every year even if they feel fine, so even though you feel you see fine your eyes still need their “physicals”.