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Ophthalmology & Optometry/Large change between eyeglasses prescriptions, but not between contact lens prescriptions=error?


I usually wear contact lenses, but have been wearing glasses more recently due to eye irritation. My glasses are about 4 years old. For these reasons, I decided to get a new pair of glasses that would reflect my more recent prescription from several months ago.

However, when I pulled out my old and new prescriptions for glasses and contact lenses, I noticed that the contact lens prescription has changed only very slightly, while the glasses prescription appears to have changed more radically.

I'm hoping that if I provide the numbers, you will be able to tell me whether they make sense, or if a mistake has been made and I should get reexamined before getting new glasses.

Old Contact Lens:
OD -2.50, -2.25, 20
OS -5.50, -1.25, 160

New Contact Lens:
OD -2.75, -2.25, 20
OS -5.50, -1.25, 170

Old Glasses
OD -2.50, -2.25, 15
OS -5.75, -1.25, 176

New Glasses

OD -5.25, +2.25, 105
OS -7.25, +1.50, 86


Hi Jamie, it's confusing because of the different convention in writing Rx's: using +cylinder vs minus cylinder.  If you convert one to the other there is only a little difference, similar to the old/new contact lens rx. If you search for how to convert b/t the two conventions, you will see only a little stronger new.  Don't worry about it, they are similar and it all makes sense.

The new glasses converted would be:
od -3.00-2.25 axis .15 and
os -5.75-1.50axis176

Mitch Axelrod, OD

Ophthalmology & Optometry

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Mitchell Axelrod


I'm happy to answer questions about eye exam findings and procedures, glasses and contact lens types/prescriptions/problems. I can also answer questions about general eye conditions/diseases. I do not answer questions concerning surgical techniques/procedures. Please state your age or within a small range when asking questions, as it is often important.


Optometrist 19 yrs.

Doctor of Optometry, cum laude; Residency in Ocular Disease

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