The two most commonly experienced eye related problems (not including needing glasses or contact lenses) are dry eyes and ocular allergies. Although some symptoms are similar, there are distinct differences between the two eye conditions. In fact, dry eye and ocular allergy can occur simultaneously. If you are a contact lens wearer, both dry eye and allergies can make wearing contact lenses more difficult.
Tears are not made of just water. There are numerous components to tears, but think of them simply as having three layers – mucin, water and lipids. A dry eye situation occurs when either too little water/mucin is produced, or if too little lipid is produced. The lipid layer is the outer layer of the tears and its primary role is to prevent the tears from evaporating or spilling over the lid margins. The lipid layer is produced by glands on the edge of the lids called meibomian glands. The majority of dry eye is caused by a decrease in this lipid layer. Certain medical conditions can also cause dry eye. The most common symptoms include burning, a sandy, gritty feeling, redness and sometimes reflex tearing.
While eye allergies can also cause redness and tearing, the main symptom is itching. An ocular allergy is caused by sensitivity to a substance that is not usually harmful. When the allergen interacts with cells called mast cells, a substance called histamine is released which causes itching, redness, and swelling. Most allergies are due to environmental factors like pollen, cat dander, dust mites, etc. There are also more serious ocular allergies that require medical intervention.
Treatment is different for dry eye and ocular allergies. Dry eye treatment includes treating the meibomian glands, the underlying inflammation, and using tear lubricants. The treatment for ocular allergy includes using antihistamine/mast cell stabilizers (to prevent the release of histamine from the mast cells), artificial lubricants, cool compresses and avoidance of the allergen (if possible).
For contact lens wearers, your doctor may choose a contact lens with a material that is more resistant to drying out like CooperVision’s Proclear lenses. For allergy sufferers, wearing a 1 day disposable lens will give the best chance for successful lens wear. CooperVision’s Proclear 1 Day and Proclear 1 Day Multifocal lenses provide the best option as they are resistant to drying out and get replaced each day.
Many people use over- the- counter products to self- treat dry eye and ocular allergy problems. It is estimated that the cost of doing that exceeds the cost of prescription products which are more effective. If you feel that you have dry eye or ocular allergies, see your eye doctor for a complete evaluation and recommendations for the best treatment options.