Allergic reaction

An allergic reaction is generally defined as an excessive immune system response to a stimulus (eg. chemical substance), which comes into direct contact with the human body. Allergies can be caused by pollen, dust, mold, hair, cosmetic products or food. Allergic reactions can also be caused by various kinds of materials that come into contact with sensitive skin or mucous membranes. Allergic reactions to contact lenses may be caused by the material from which they are made. A reaction may also be caused by eye drops used, to moisten the lenses, or by solutions, which are used to disinfect them. Prevention of allergic reactions to contact lenses is most easily achieved by choosing contact lens solutions with a minimum content of chemicals and also by practicing proper lens care, including mechanical cleaning (rubbing) and regular disinfection.