Asthma Medications that Can Cause Long-Term Vision Problems
Corticosteroids inhalers are considered the first line of defense in controlling asthma on a long-term basis because they locally reduce inflammation in the airways quickly upon inhalation. If a corticosteroid inhaler is not effective in controlling asthma attacks, physicians can prescribe oral or intravenous corticosteroids. However, two major side effects of corticosteroids, regardless of the form prescribed, are cataracts and increased eye pressure, which can lead to glaucoma.
A cataract is a cloudiness of the lens of the eye that impairs vision and can eventually lead to blindness. Symptoms include a gradual blurring of vision, increase in glare from lights (especially while driving at night), loss of central vision, poor vision in sunlight and, in later stages, a milky whiteness appearing on the pupil. Cataracts can be successfully removed surgically, but only after they have occluded the entire eye and only one eye can be done at a time if both eyes have been affected. The majority of patients who elect to have their cataracts removed report improved vision after surgery. Also, patients can live comfortably without cataract surgery if there are no symptoms or there is only minor vision loss.
However, vision loss due to glaucoma is permanent. There are a few different types of glaucoma, depending on what causes it and where it is located in the eye. Use of corticosteroids causes open-angle glaucoma, which means that the drainage canals inside the eye are partially blocked and the fluid cannot drain properly. This causes a build-up of pressure in the inner eye, known as intraocular pressure or IOP, resulting in damage to the optic nerve and can lead to irreversible blindness if not treated promptly.
Most people with open-angle glaucoma typically have no symptoms for a long time because loss of vision occurs very slowly as pressure in the eye gradually builds. The most common symptom, when it occurs, is loss of peripheral vision in both eyes. For treatment, eye drops are used to stop the vision loss by either decreasing the amount of fluid in the eye or increasing the amount of flow out of the eye and must be used for the rest of the patient’s life. Surgery would only occur if the eye drops failed to stop the progression of vision loss and/or failed to decrease the amount of pressure in the eye.