Allergies flare up. This way, you Vision rx20 can start some sort of treatment or prevention program before you begin feeling symptoms. If you have PAC, you may want to routinely have appointments with your ophthalmologist to make sure that your eye allergies are being monitored. Occasional flare-ups will make it necessary to keep your eye doctor up to date with your condition. You may also want to consult an allergist (a doctor who specializes in allergic diseases, like nasal allergies and allergic asthma). Important..