News and Advice on Myopia and General Eye Care for Patients and Professionals

Why FDA Approval Matters

Paragon Vision September 04, 2019 Nearsighted, CRT Lenses, Contact Lenses, Orthokeratology, FDA Approved, Myopia, Ortho-K, optometrist, corneal refractive therapy, CRT, vision, nearsightedness, eyes


FDA approved, cleared, listed, and registered; what do they all mean? From our food to our cosmetics to medical devices – it is up to the FDA to regulate our products and protect us from potentially harmful foods, drugs, chemicals, and materials. You may have heard of FDA approved, but have you heard of any of the other FDA classifications such as cleared or listed? With the rise in skepticism towards healthcare we believe it is imperative to address what each of these labels mean.

FDA Approved  

FDA approval requires a pre-market application (PMA) that demonstrates that a device is safe and effective when used. The review is stringent with a highly involved clinical investigation and the application must include submission of clinical data to support claims made for the device.1

There are different classes of medical devices that the FDA reviews. Classes play a big role in whether a product is approved, cleared, etc.

Medical devices are classified based on the risks associated with the use of the device. Devices are classified as Class I, Class II, or Class III, with Class I being the lowest risk and Class III the highest risk.

Class III devices sustain or support life, are implanted, or present potential high risk of illness or injury. An example of a Class III device is a pacemaker. With the high stakes of Class III devices, they go through a more intense approval process than other devices and products with the FDA.

Because Paragon CRT® contact lenses are worn overnight to reshape the cornea, it is considered a Class III device. Paragon CRT® are the first overnight orthokeratology contact lenses to be FDA approved (approved in 2002). The material to manufacture the lenses are also manufactured by Paragon Vision Sciences and is FDA approved.2 With this double-dose of regulation we hope this gives a patient or parent of a patient peace of mind.

97.6% of Paragon CRT® patients find that their lenses meet or exceed their expectations!

FDA Cleared

To become FDA cleared a product must show the FDA that it is similar to another product that the FDA has already given approved or cleared. FDA cleared involves Class II and some Class I products. Here you see devices such as powered wheelchairs and pregnancy tests.1 This process is less strenuous and is dependent on what is already legal and in the market.

If you are a parent or patient with a concern for FDA regulation, then it is important to know the distinction between FDA approved and FDA cleared.

53% of medical devices fall into Class II while 9% of medical devices are Class III.1

FDA Listed and Registered

When we get to 35% of medical devices, they fall into the Class I category. 93% of these devices do not have to submit the same type of detailed and clinical information that other higher-class medical devices need to do in order to receive FDA approval or FDA clearance. To sell and distribute their devices Class I manufacturers need to register their establishment and list their devices with the FDA.

Class I devices have low risk. You see tools such as manual stethoscopes or bedpans in this category.1 While you shouldn’t be alarmed to find that your bandage is a Class I device3, you should still be aware of the differences among FDA approval, cleared, and listed and registered.

With today’s public having a large interest in medical research and knowledge combined with the widespread of misinformation, we hope that parents and patients can have a general understanding of the different FDA classifications.

Sigh of Relief

Take a deep breath and know that your Class III products go through a comprehensive review process. Tests, research, and clinical play a role in FDA approval. Because of this FDA approval for Class III devices is important for public health and safety.

We know overnight contacts sound strange to some. Conventional contacts are dangerous to wear while you sleep.4 Paragon CRT® contact lenses on the other hand, are made to sleep in and are FDA approved for overnight wear. Paragon CRT® are for nearsighted patients who struggle to see distant objects clearly. The lenses are worn while you sleep and gently reshape the cornea so light is focused correctly on the retina. In the morning you remove your lenses for clear vision without the need for glasses or daytime contacts.

As part of FDA regulations Paragon CRT® can only be prescribed by a Paragon CRT® certified eyecare professional. Eye doctors must be trained and certified to fit and dispense our lenses. If you are interested in finding a certified eye doctor you can use our doctor locator tool. Click the button below to see if there are any Paragon CRT® certified doctors in your area.

Find a Certified Doctor


[1] Center for Devices and Radiological Health. (2019, April 9). Consumers (Medical Devices). Retrieved August 6, 2019, from

[2] FDA Approval Letter

[3] Product Classification. (n.d.). Retrieved August 6, 2019, from

[4] Cope, J. R., MD, Konne, N. M., MPH, Jacobs, D. S., MD, Dhaliwal, D. K., MD, Rhee, M. K., MD, Yin, J., MD, PhD, & Steinemann, T. L., MD. (2018, August 17). Corneal Infections Associated with Sleeping in Contact Lenses - Six Cases, United States, 2016–2018 | MMWR. Retrieved August 6, 2019, from