Contact lenses are very safe medical devices, to be used after an examination and a prescription from your ophthalmologist. After assessing the health of your eyes and any problems, your eye doctor can diagnose your refractive errors and recommend the most suitable type of contact lenses.
Even when following all your doctor’s advice, some discomfort or problems may occur. We describe them below.
If your eyes are very red, it could be the start of dry eye or an eye infection, such as Acanthamoeba keratitis; if your vision is not as clear as before, your lenses may be dirty and your eyes may be swollen from lack of oxygen.
A feeling of discomfort, on the other hand, may be caused by eyelashes, debris or traces of make-up trapped under the lens – perhaps worn badly or even inside out – or it may be a sign of a corneal abrasion, the start of an ulcer, dry eye or an infection. Lenses can also become foggy and hard to use.
We therefore recommend checking for these symptoms every day. If you think you have a problem, first remove the lenses and check whether dirt is the cause by soaking them in disinfecting solution; if the discomfort continues, call your eye doctor. If there is a problem, the sooner an expert looks at it, the better.
Making sure your eyes get enough oxygen
Although contact lenses are safe, they sit directly on the eye and cover the whole cornea (or part of it, in the case of gas permeable lenses), so they reduce the amount of oxygen reaching the eye.
Yet a good oxygen supply is essential for eye health. You can limit the effects of oxygen deprivation by following the replacement schedule set by your eye doctor, changing your lenses as advised and, for example, choosing modern silicone hydrogel lenses.
These are soft lenses made of a material that lets through more oxygen than conventional lenses, and they can be safer for the eyes in the long term.
Another option is rigid gas permeable (GP) lenses. They have a smaller diameter than soft or silicone hydrogel lenses.
They cover a smaller part of the cornea and move noticeably with each blink, allowing the tear film underneath to be renewed. Both factors reduce the risk of eye problems.
Moisture for dry eyes
Lenses, especially less permeable ones, can cause dry eyes. Today in particular, long hours in front of computers and other screens make a reduced tear film even more common.
You can help with specific products that moisturise the eye, such as eye drops, or the lens, such as rewetting drops. There are also contact lenses for dry eyes that keep the eye well hydrated all day thanks to moisturising ingredients such as hyaluronic acid.
For people with dry eyes, daily lenses are by nature the most suitable solution, thanks to their short wearing time.
Choosing the right size for your eyes
Check the size: contact lenses must fit your eyes as closely as possible, just like clothes or shoes. So contact lenses, too, need to be tried on.
They come in different sizes (look at the value next to “DIA”). That is why it is best to consult your eye doctor and always buy the lenses best suited to your eyes and to any changes in your vision.