Do Not Use an Incorrect Contact Lens Prescription While Waiting for a New One
You should not wear contact lenses with either over-corrected or under-corrected power while waiting for your new prescription—instead, use your most recent correct prescription or switch to eyeglasses temporarily. Wearing an incorrect prescription, whether over or under-corrected, can cause visual discomfort, reduced visual performance, and is not recommended by current guidelines 1.
Why This Matters
The 2023 American Academy of Ophthalmology Refractive Errors Preferred Practice Pattern explicitly lists "incorrect prescription" as a complication and difficulty of corrective lens wear 1. Contact lenses are medical devices that require a valid physician's prescription, and wearing lenses with the wrong power—even temporarily—goes against proper contact lens management 1.
The Evidence on Incorrect Corrections
Research demonstrates that even small prescription errors (±0.50 D) significantly affect:
- Binocular visual acuity (measurably reduced)
- Negative relative accommodation (impaired)
- Overall lens acceptability (patients report discomfort and unacceptability) 2
Importantly, subjects in this study perceived incorrectly powered lenses as inferior and a considerable proportion found them unacceptable, supporting the need for accurate refractions 2.
What You Should Do Instead
Best Option: Use Your Current Valid Prescription
- Continue wearing your most recent correctly prescribed contact lenses until you can obtain the new prescription
- Contact lenses should be "worn and replaced according to the schedule prescribed by your doctor" 1
Alternative: Switch to Eyeglasses Temporarily
- Use eyeglasses with your current prescription while waiting
- This is safer than wearing an incorrect contact lens prescription
- Eyeglasses are also protective, which is especially important 1
Get Your New Prescription Promptly
- Contact lens wearers should have examinations every 1-2 years to monitor for adverse effects and update prescriptions 1
- Never obtain contact lenses without a valid prescription—this is illegal under federal statute 1
Important Caveats
Neither over-correction nor under-correction is appropriate as a temporary measure. The guidelines emphasize that:
- Small changes in refractive corrections in asymptomatic patients are generally not recommended 1
- The need to correct refractive errors depends on the patient's symptoms and visual needs 1
- Proper contact lens fitting requires careful attention to optimize fit, including size, centration, and movement 1
Special Circumstances
The only contexts where intentional under-correction or over-correction might be discussed involve:
- Anisometropia management (large differences between eyes), where under-correction may reduce symptomatic aniseikonia but comes "at the expense of acuity" 1
- Post-refractive surgery complications requiring specialized contact lens fitting 3, 4
These are specific clinical scenarios managed by eye care professionals—not situations where you should self-manage with an incorrect prescription.
Bottom line: Contact your eye care provider to obtain your new prescription rather than wearing incorrectly powered lenses. If there's a delay, continue your current correct prescription or use eyeglasses temporarily.