Contact Lens Solutions: Multipurpose and Hydrogen Peroxide
If you wear or intend to wear soft bi-weekly or monthly contact lenses, you need to use a disinfecting solution to ensure your contact lenses are safely sanitized and good-to-go so you can wear them multiple days in a row. Even though the solution might be completely clear and odourless, you might be wondering why you have to pay for it. But, it is because the solution, is more than just water!
Since 2018, Health Canada regulates contact lens solution as medical devices, meaning that anyone who makes and/or sells them must have a medical license and follow strict guidelines established by the Canadian Food and Drugs Regulations as well as follow the Safety and Effectiveness Requirements for Contact Lens Disinfectants (2018).
So basically, as long as you follow the instructions on the box of the product, wash your hands and properly rub both side of your contact lenses before putting them in the solution (only with multipurpose or saline solution), they will be disinfected properly.
Why do you need to disinfect your contact lenses?
One of the main goals of using these solutions is to eliminate or greatly diminish the number of microorganisms that end up on your lenses such as the following bacteria (we challenge you to read them all in one go without fumbling!): Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Candida albicans, Fusarium solani and Acanthamoeba sp. These can all cause an eye infection when they become overgrown. The solution also aims to remove the proteins and lipids that your tears deposit on your contact lenses throughout the day, because a buildup can cloud your lenses and cause discomfort. Finally, they aim to eliminate minuscule debris that end up on your contact lenses while you wear them like, dust, makeup or hair products.
Here are the two main categories of contact lens solutions:
It takes about 4 to 6 hours for these solutions to thoroughly disinfect your lenses. They are “multipurpose” because they can be used to clean, disinfect, rinse and store your contact lenses. They are usually cheaper than hydrogen peroxide solutions and you can use the same product for all of your contact lens needs. Since it is safe for your cornea, you could take them out and put them back on later if needed, as long as you always store them in fresh solution and make sure to thoroughly disinfect them at least once a day (usually overnight).
Hydrogen Peroxide Solutions
While Hydrogen Peroxide Solutions do not contain any preservative and are therefore safer for sensitive or allergy-sensitive eyes (which is why people who experience discomfort with multipurpose solution will often switch to a hydrogen peroxide solution) they tend to be a little pricier and they take longer to thoroughly disinfect your contact lenses (at least 6 hours).
Since hydrogen peroxide should never come in contact with your cornea, it needs to be neutralized and turned into water and oxygen before you can safely wear your contact lenses again. With some solutions, you’ll have to add a neutralizing tablet once the disinfecting process is over. With other solutions, they will provide a storage case that has a built-in neutralizer, meaning that you don’t have to do anything for the whole process to be completed. If you ever need to rinse your contact lenses during the day for any reason, you’ll need a multipurpose or a saline solution to be able to wear them right after. It must be noted that leaving your contact lenses for a long time in the case when the solution has been neutralized is not a great idea, since the neutralized solution doesn’t prevent bacteria from growing, so occasional contact lens wearers should avoid this solution.
Ultimately, your Optometrist will help you choose the right type of solution and the right brand for you. But we hope this guide gave you an idea of the option that would be best for you and that you’ll have something new to teach your friends the next time you see them!