The eye contains a fluid called aqueous humour that provides it with the nutrients it needs . This liquid is produced and circulates inside the eye before draining through a small canal that empties into the bloodstream. If too much aqueous humour is produced or if the liquid doesn’t drain properly, pressure in the eye increases, which leads to a condition called ocular hypertension. This hypertension, which is different from arterial hypertension, can affect just one or both eyes.
There are different types of glaucoma, depending on how the fluid is kept from draining.
In 90% of cases, fluid obstruction in the eye is gradual and goes unnoticed. However, this type of glaucoma causes permanent damage in the long term.
Glaucoma affects 1% of people over the age of 40. The disease also increases with age, affecting 4% of people aged 80 or over. Black people also develop glaucoma more often. We don’t know exactly why certain people get glaucoma, but the disease has a major genetic component. Diabetes, hypertension, hypothyroidism and nearsightedness are risk factors. Glaucoma may also occur after trauma (e.g., a blow to the head), be caused by a tumour near the eye, or be caused by certain medications (e.g., prolonged corticosteroid use).
Glaucoma can be controlled through the daily and consistent use of eye drops. To prevent damage, you must use these medications every day for life while following the recommendations of your eye care professional.
Did you know?
Your optometrist can renew or adjust your glaucoma prescription in collaboration with your ophthalmologist.
Like any medication, eye drops can cause side effects. In this case, the side effects include tingling, burning or itching of the eye, glare, or blurred vision. These symptoms usually occur when the drops are applied. They generally don’t last very long (less than 5 minutes) and tend to decrease after you’ve used the product for a few weeks.
Some medications, even when applied directly to the eye, can be absorbed into the blood and cause side effects in the rest of the body. If you have new symptoms and you don’t know what’s causing them, talk to your pharmacist.
Some medications, such as cold and flu or allergy medicine, can block the flow of aqueous humour and aggravate glaucoma. See your pharmacist before buying OTC medications.
In all Quebec pharmacies, OTC medications carry a drug caution code that indicates the precautions to take when using them. People who suffer from glaucoma should avoid caution code “B.” Ask your pharmacist for more information about drug caution codes.
The goal of traditional surgery or laser surgery is to make an opening in a specific location of the eye so that the aqueous humour can drain. Surgery is generally indicated for people who don’t respond well to medication or who have narrow-angle glaucoma.
If you have glaucoma, remember that your pharmacist is a great partner to help you manage your medication and maintain your eye health.