PRESCRIPTION OF CONTACT LENSES

The Importance of Buying Prescription Contact Lenses

Contact lens prescriptions are only intended to last one to two years for good reasons. During that time your eyesight can change, either by getting better or by worsening. Wearing the wrong prescription can cause major damage to your eye, so the FDA have put strict rules to the game of prescribing them.

They best way to ensure you’re wearing the correct prescription is to have annual exams through your eye care practitioner.

Importance of Verification of Prescriptions

Sellers of contact lenses may provide them to you when you present your prescription in person, by fax, or by email if the prescription has been scanned and attached to the email. Also you can authorize the seller to verify the prescription via direct communication with you. An example of direct communication would be contact through the telephone or leaving a voicemail.

Verifying your prescription with the person who sells them to you is a great way to avoid any legal trouble for them, and it ensures you that you’re receiving the correct prescription. When verifying a contact lens prescription, anyone who sells contact lenses must provide the following information to you. Some of the information is found on the label, while other information can be found in provided paperwork at fitting appointment.

Importance of Prescription Expiration Dates

It’s so important you are aware of the expiration date of your contact lenses. To make sure your eyes remain healthy you should not order lenses with an old prescription.

Also, it’s not a good idea to stock up on lenses right. It’s much safer to be rechecked by your eye care practitioner. If you have not had a check-up in the last one or two years, you may have problems with your eyes that you are not aware of. This could result in the worsening of your eye’s health.

Understanding Your Contact Lens Prescription

Eye care professionals use standard terms, abbreviations and measurements to write out prescriptions for patients needing contact lenses. There are very specific items that must be placed on the label. Any label that doesn’t include these items is subject to legal consequences, and the proper authorities should be contacted.

Prescriptions last one to two years, depending on the minimum required by state law and even though prescriptions for contact lenses and glasses are similar, they should never be used for one another. Once your prescription has expired, you must be refitted to gain a new prescription, and to be able to purchase new lenses. Again, it’s all in the best interest of you, the patient, to promote healthy eyes throughout your lifetime.

Rules of Prescriptions

The FTC and FDA have placed specific rules for ophthalmologists, optometrists, and licensed opticians to follow. It’s all in the best interest of the patient and includes giving a copy of the contact lens prescription to the patient at the end of the contact lens fitting, even if the patient doesn’t ask for it, and providing or verifying the contact lens prescription to anyone who is designated to act on behalf of the patient, including contact lens sellers. In any response to a verification request, contact lens prescribers must correct anything wrong with the prescription, inform the seller if it’s expired and/or specify the reason if it’s invalid.

Prescribers cannot disclaim liability or responsibility for the accuracy of an eye examination, however they may require you to pay for the eye exam, fitting and evaluation before giving you a copy of the contact lens prescription, but only if the prescriber also requires immediate payment from patients whose eye exams reveal no need for glasses, contact lenses, or other corrective eye care products. Proof of valid insurance coverage counts as payment for purposes of this requirement, so don’t be fooled into paying extra.

Decoding the Terms

Below are brief descriptions of the items that should be on the label of your contact lenses and what they mean to you and your eye care professional. In addition to the listed items below, some prescriptions may note how often your lenses must be replaced. The time isn’t required by law, as some eye care professionals tell you in person or have it written down on instructions.

OS/OD/OU

OS, or Ocular Sinister is a Latin term for the left eye. OD, or Ocular Dexter is Latin for the right eye. If you see an OU, meaning ocular uterque on your label, it means the prescription is the same measurement in both eyes.

BC

This stands for base curve. It’s the back curvature of your contact lens and is measured in millimetres. For best fit, comfort and eye health it’s prescribed to match or complement the curvature of your cornea. The lower the number, the steeper your cornea.

DIA

This stands for the diameter. It’s the distance, measured in millimetres, from one edge of your contact lens to the other edge. It’s important because it determines where on your eye the edges of the lens will rest. If the diameter is wrong, it can cause irritation and/or abrasions.

CYL

This stands for cylinder, and is necessary if your lenses are correcting astigmatism. Measured in dioptres, the cylinder shows the extent of your astigmatism. A negative sign means Myopia (near-sightedness) astigmatism and a plus sign means Hyperopia (farsightedness) astigmatism.

AXIS

This isn’t short for anything, simply referring to the axis. It’s a necessary measurement for lenses that correct astigmatism. The axis is measured in degrees and indicates the orientation of the cylinder in the lens and is used in order to compensate for the cornea’s oval, rather than round, shape.

ADD

This stands for add power and is used in bifocal lenses. The add power is measured in dioptres, and even if a plus sign is not written on the prescription, it is automatically assumed.

COLOUR

This is included in the prescription only if the lenses change or enhance the colour of your eyes. Or, in the case of a special effect, a particular design is written here, such as “cat-eyes”. Colour and style names vary from brand to brand.

BRAND

The lens prescriptions, at times, indicate a specific brand. The retailers must sell you that brand and no other. In the case of contact lenses that are sold by eye care professionals, substitutions of an equivalent natural brand or private label brand may be permissible.