Patients often ask me, “Can I sleep in my contact lenses?” Since my goal as an eye doctor is to protect the health of their eyes first and foremost, I like to share some physiology of the eyes with them, how contact lenses work, and why I never recommend sleeping in contacts on a regular basis.
Your Corneas Do Not Have A Blood Supply
The cornea is the clear front of your eyes. This is where the light enters as it travels to the retina. The cornea provides about two-thirds of the refractive (light bending) power of your eyes. A healthy, clear cornea is essential for clear vision.
One of the reasons the cornea is clear is because there are no blood vessels. The cornea “breathes” by taking in oxygen from the tears and giving biochemical waste back into the tears. A healthy cornea depends on this exchange.
You Cover Your Corneas When You Sleep
When you close your eyes to sleep you cover your cornea. This reduces the amount of oxygen getting through. This is normal and it typically takes your corneas only a short time to recover in the morning from any oxygen loss.
When You Wear Your Contacts You Also Cover Your Corneas
Your contact lenses also cover your corneas, reducing oxygen supply. Of course, this varies depending on what type of contacts you wear, but nearly every contact has some negative effect on corneal oxygen supply.
I Do Not Recommend Sleeping in Contacts on a Regular Basis
Because of the above I do not recommend sleeping in contact lenses for any significant number of days or on a regular basis. I have experienced patients having healthier eyes and more comfortable lenses by discontinuing sleeping in their contact lenses. I do not object to patients occasionally wearing contacts overnight. For example, contact wearers who go camping, visit friends overnight, or are on-call, like firemen are typically safe to wear their contacts to sleep.
What I Recommend for Healthy Contact Lens Wear
For patients who want to maintain healthy corneas and reduce the risk to their ocular health I recommend the following:
Daily contact lenses
Fresh lenses every day
No chemicals in your eyes
You save money by not needing solution
Wear your glasses for 2-hours per day
This is typically done in the evening
It allows the cornea to “breathe” unimpeded
I call this “Peace and Love for Your Eyes”