Allergic eye disease is one of the most common ocular surface diseases, of which allergic conjunctivitis is the most common type. According to statistics, about 1/5 of patients in ophthalmology clinics suffer from allergic eye diseases, of which allergic conjunctivitis accounts for about 50%, which shows that allergic conjunctivitis is one of the most common diseases in ophthalmology. Itchy sensation in the eye is a common symptom in almost all types of allergic conjunctivitis, but other symptoms such as tearing, burning sensation, and discharge lack specificity and are often easily confused with other ocular surface diseases. The clinical manifestations are signs of diffuse conjunctival congestion, edema and papillae and follicular hyperplasia, which become more severe the closer to the corner part of the eye. Patients usually have no eye pain and no significant visual impairment with normal pupils. If a family member suffers from allergies, the likelihood of it being an allergic reaction is high, and its allergens are basically the same as those of allergic rhinitis. Allergic conjunctivitis is an allergic reaction to the conjunctiva caused by exposure to allergic antigens, which is primarily an IgE-mediated type I allergic reaction. Anyone who is genetically or somatically susceptible to specific antigens can, upon exposure to such antigens, result in tachyphylaxis or delayed allergic conjunctivitis, often accompanied by allergic rhinitis, etc. There are 4 main types of allergic conjunctivitis: allergic conjunctivitis (including seasonal, perennial, and contact), giant papillary conjunctivitis, springtime keratoconjunctivitis, and atopic keratoconjunctivitis. Seasonal allergic conjunctivitis is most common in young and middle-aged people, with a rapid onset, occurring upon contact with the allergen and remission of symptoms away from the allergen, while the main difference between perennial and seasonal is the presence of allergic symptoms year-round. Spring keratoconjunctivitis is most commonly seen in pediatric patients and often occurs or worsens during the spring and summer months. Some spring keratoconjunctivitis and atopic conjunctivitis can produce serious corneal complications and even compromise vision. Many allergic conjunctivitis are self-limiting, so the main goal of treatment is to reduce symptoms and avoid sequelae. Allergen removal is the most effective treatment, and contact with possible allergens should be avoided as much as possible, such as paying attention to mattress hygiene, avoiding exposure to pollen, stopping wearing contact lenses, and maintaining indoor air circulation. In addition to oral anti-inflammatory drugs, topical antihistamines such as emetine fumarate (Emetine) eye drops can achieve more satisfactory results, while mast cell stabilizer – sodium cromoglycate eye drops can both treat and prevent allergic conjunctivitis, and is also a more commonly used drug, but generally effective after a week, often because of the preservative component. It cannot be used for a long time because of its preservative content. Pralophine eye drops are often used as an adjunct because they are non-steroidal anti-inflammatory (non-hormonal). In some mild cases, the use of artificial tears such as sodium vitrate drops can provide significant relief. Glucocorticoids are usually used when other medications are ineffective, and should be used with caution under the guidance of a physician because of their side effects. In addition, desensitization and surgery are also available. Allergens are the culprit As with all allergic diseases, allergic conjunctivitis occurs when the mucosal tissue of the conjunctiva of the eye comes into contact with allergens in the form of inflammation of the conjunctiva. Allergic conjunctivitis is caused by an allergic reaction of the conjunctival mucosal tissue of the eye to a specific allergen. Allergens are substances that cause allergies and are medically called allergens. These allergens enter the eye and bind to immunoglobulin E (IgE) on the mast cells of the conjunctiva, causing the mast cells to release histamines, which cause small local blood vessels to dilate, producing symptoms of redness, swelling and itching. Allergens include pollen, dust, cold and humid air, dust mites, animal hair, soap, perfume, cosmetics, medications, contact lenses and their care solutions, etc. Because people’s individual constitution varies greatly, allergens vary from person to person. The most common allergen causing allergic conjunctivitis is plant pollen, and the symptoms of this allergic conjunctivitis tend to change seasonally. If the allergen is dust, dust mites or animal hair, etc., because these allergens are present year-round, the symptoms of allergy are also continuous throughout the year, and the symptoms are milder, but may also worsen with the seasons. The typical symptom is itchy eyes The main manifestation of allergic conjunctivitis is itchy eyes. Unlike ordinary itching, this itch is often very intense and unbearable, so it is medically known as odd itch. It also manifests as a congested, edematous conjunctiva with mucus discharge, often accompanied by redness and swelling of the eyelid skin. And the closer to the corner part of the eye, the more serious the situation is. Patients usually have no eye pain and no obvious visual impairment, with normal pupils. The symptoms can change well and badly with the seasons and recur, which means that in addition to being closely related to the patient’s allergic constitution, climate change and the patient’s activities are important factors in the onset of the disease. Generally speaking, the symptoms are aggravated on warm and dry days when flowers are in bloom. Odd itching is what most patients with allergic conjunctivitis feel. In addition, the conjunctiva is congested and edematous, with mucus discharge and red and swollen eyelid skin. Allergic conjunctivitis treatment should pay attention to daily protection If allergens cannot be identified at the moment, then, first of all, it is important to improve the living environment, especially the air quality or indoor temperature, so that the influence of allergens can be reduced. Second, pay attention to nutrition and exercise, regularity of life and rest, and strengthening of physical fitness. Because the improvement of physical health can make the body’s potential to fight against allergy attacks increase, and reduce and slow down allergy attacks. Again, local cold compresses or ice packs can be applied to the eyes to reduce discomfort, artificial tears can be used to spot the eyes locally, and rinsing can also be used to significantly reduce the concentration of allergens and inflammation-causing factors and improve symptoms. Medication mainly includes the use of anti-allergy drops such as sodium cromoglycate, Rimadyl, and Emetin. There is a foreign market for ophthalmic solution that combines antihistamine and mast cell stabilization (Patanlo), which can shorten the improvement of symptoms and treatment time and is currently being promoted in China. If the symptoms of allergic conjunctivitis are not relieved by various treatments, glucocorticoid eye drops can be used for a short period of time (clinically commonly used are imported drugs such as Flomax eye solution, Bactrim eye solution, and domestic drugs such as 0.5% cortisone eye solution). In case of combined ocular bacterial infection, topical antibiotics can be used. It is important to note that anti-allergy treatment can only control the symptoms of allergy, but it is difficult to completely cure allergic conjunctivitis, which is one of the reasons why allergic conjunctivitis remains untreated. As children are not yet mature, the mucous membrane of the conjunctiva is extremely permeable, making them a natural candidate for allergic conjunctivitis, while adults with allergic conjunctivitis have a history of allergies in childhood. Therefore, we would like to remind you that if your child rubs their eyes a lot or blinks frequently at a certain time, they may be suffering from allergic conjunctivitis, and ordinary anti-inflammatory eye drops will not help at all, or even lead to other eye diseases due to long-term wrong treatment.