Contact Lens Fitting and Assessment


Contact lenses are a comfortable and effective solution for correcting vision. Most eyeglass prescriptions can be fit for contact lenses, including most unique prescriptions.

The continued research and innovation in the contact lens industry has provided various types of lens technologies, materials, oxygen contents, etc. In Ontario, contact lenses are regulated medical devices and require a specialized prescription (different from a glasses prescription) from an eye health professional before they are worn. This is due to the fact that contact lens wear can increase the risk of an eye infection or inflammation that can lead to vision loss if left untreated. As such, annual contact lens examinations are necessary to ensure the eyes are healthy enough to continue wearing contact lenses. 

What is required before I get contact lenses for the first time?

Step 1 – Comprehensive Eye Exam

Before being fit with contact lenses, a comprehensive eye exam must be performed. This in-depth exam is tailored specifically towards determining your contact lens prescription and will include tests not found in routine eye exams.

The overall health of the eye, including the front surface of the eye (cornea, conjunctiva, eyelids etc) will be carefully assessed for any potential conditions that could affect the ability to comfortably and safely wear contact lenses.

 Step 2: Contact Lens Fitting

The Optometrist will discuss your lifestyle and determine the type of contact lens that is best suited for you (some of the things discussed include: brand preferences, materials, disposal schedule, among others). Measurements of eye curvature and prescription will also be taken.

Step 3: Fitting

Contact lenses are not one-size-fits-all. Many factors must be considered to determine which contact lens is right for you.

A poor fitting contact lens can cause discomfort, poor vision, dry eye, etc.

A contact lens fitting assesses the shape and size of the eye (and its surface) and ensures that the contact lens is centered on the eye and moves appropriately.

 Step 4: Contact Lens Insertion and Removal Training and Hygiene

The optometrist will teach you about contact lens care and maintenance, which is important to follow in order to to reduce the risk of an eye infection. 

The optometrist or optometric assistant will provide in-person training on your first contact lens insertion and removal from the eye.

Step 5: Contact Lens Trial Period

You will be provided with a set of trial contact lenses to go home with. For the period of 1 week, you can test the contact lenses and ensure good comfort and vision. After your trial period, a follow up appointment will be scheduled to confirm your contact lens selection, before the final contact lens prescription is given. 

How often should I have a contact lens assessment if I already wear contact lenses?

Annually. Due to the risk of developing an eye infection, poor oxygen exposure to the eye and other conditions that can cause contact lens intolerance, annual eye health and contact lens assessments are necessary to ensure that you can wear contact lenses for years to come.

 Is it safe for me to sleep with my contacts?

No. Sleeping in contact lenses significantly increases the risk of eye inflammation or infection, which may have the potential to harm your vision. There are a few types of contacts available that allow for overnight wear, however these are only approved for patients in particular cases. Most contact lenses are not designed for overnight use.

If you sleep overnight in contacts that are not meant for overnight wear, you may experience:

  • Irritation
  • Redness
  • Inflammation
  • Pain
  • Dry/sandy feeling

Will my contact lens prescription change?

 Yes. Our eyes naturally change over time, which means that our prescription could also change. As the eyeglass prescription changes, so does the contact lens prescription. 


If you are experiencing any irritation or pain in your eyes, please remove your contact lenses immediately and book an appointment with your Optometrist.