Back to the articles

What happens when you leave contact lenses in too long

Eye Health

structure image What happens when you leave contact lenses in too long


Our experts at ContactsDirect are often asked, “How long can I wear my contacts, and what would happen if I wore them longer than the recommended time?” Wearing contacts too long can have serious consequences for the overall health of your eyes. Generally, it is recommended that you wear your contacts no more than 12 hours a day.

How long is too long to wear your contacts?

You might want to wear your contact lenses as long as possible to save money, or you have a recently expired contact prescription. But pushing the length of wear past the recommended time makes your eyes susceptible to complications and conditions that can negatively impact your overall eye health and vision.

To understand how long you should wear contacts, you must first know the different contact lens types available and their FDA-approved length of wear time; these include:

  • Daily wear lenses: can be worn daily but removed before sleeping and stored with an appropriate saline solution. The length of wear varies by the manufacturer and the condition of your eyes. Generally, they are replaced every two weeks to every other month.
  • Daily disposable: are single-use contacts worn during the day and discarded at night with a new pair applied the following morning./li>
  • Extended-wear contact lenses: these lenses are FDA approved to be worn continuously, which includes overnight. The length of wear ranges from one to four weeks, depending on the manufacturer's recommendation.

Risks of leaving contacts in too long

What happens if you wear contacts too long? It all depends on your contact lenses and their recommended wear. For instance, if your doctor recommends replacing your daily wear lenses every two weeks yet you decide to wear them longer, you risk getting severe eye conditions.

The risks and issues associated with wearing contacts too long can include:

Contact lens intolerance

Contact lens intolerance is a relatively common issue that can arise from overwearing contact lenses past their wear time. Over time and with ongoing inflammation, you risk not being able to wear contact lenses anymore.

Corneal abrasions

Corneal abrasions happen when you accumulate dirt or debris under your contact lenses that cause scratches on the cornea of your eye. When not allowed to heal, your eyes become aggravated or exposed to bacteria, which can develop into a corneal ulcer.

Corneal ulcers

Corneal ulcers, also known as infectious keratitis, is a serious eye condition that should be treated as an emergency. They present as an open sore or white-looking spot on the cornea and cause pain, eye discomfort, and light sensitivity. Corneal ulcers may be treated with an antibiotic drop prescribed by your doctor. This requires you to refrain from wearing contact lenses for an extended period to allow your cornea to heal.

Corneal hypoxia

Regardless of the type of contact you use, wearing your contacts past the recommended time will reduce the amount of oxygen available to the cornea, which results in corneal hypoxia. Mild cases and symptoms of hypoxia include blurred vision, burning, scratchy feeling, and excessive tearing—all of which are temporary. More severe cases, however, can lead to the death of epithelial cells resulting in permanent changes in vision or neovascularization, which results in new blood vessel growth on the cornea.

Damage to corneal stem cells

Your cornea maintains its transparency by rapidly replacing aged or injured epithelial cells on the cornea. The stem cells on your cornea also guarantee that the epithelial cells will get renewed and that your cornea will remain transparent. By wearing your contacts past their recommended wear time, you could risk damaging these stem cells resulting in a condition that causes an opaqueness in your cornea. In addition, there’s also an increased chance of infection, guaranteed vision loss, and other complications.

What happens if you leave your contacts in overnight?

If you sleep with your contact lenses in, you’re sure to wake up the next day with dry, bloodshot eyes that feel more tired now than before you fell asleep. When you sleep with your lenses, you may end up depriving your corneas of oxygen. Your corneas get oxygen from the air instead of your blood. Even during regular wear, the amount of oxygen that reaches your corneas is reduced. As a result, wearing lenses at night further reduces the cornea's oxygen intake, making your eyes feel dry and tired or resulting in serious eye health problems.

Your vision is crucial to your happiness and wellbeing. Keeping your eyes healthy should be your top priority. As a contact lens wearer, this starts with listening to your doctor's advice, wearing your contact lenses according to the manufacturer's recommendations, and properly caring for your lenses.