I started dating someone with pet allergies, and I have a cat. Any tips on keeping both around?

A. “Get rid of your partner, or get rid of your cat,’’ jokes Aidan Long, clinical director of the allergy unit at Massachusetts General Hospital, but he’s only partly kidding: There’s no perfect solution for helping a person with pet allergies coexist with your feline friend.

Pet allergies are caused by an overreaction of the immune system to proteins shed by animals; symptoms can range from watery, itchy eyes to a full-blown asthma attack. It’s a misconception that pet hair is the culprit for allergies. Instead, Long says, “what people are allergic to is usually a protein found in the pet’s saliva and sweat.’’ After dogs and cats lick their fur or other objects, the protein becomes airborne. The idea that some breeds are hypoallergenic is a myth, he says. Some pets will shed more of the protein than others, but Long says that it makes little difference to an allergic person, whose symptoms can be touched off by a tiny amount of allergen in the air.

The ubiquity of the allergens explains why only the most extreme measures make a difference. Simply taking the cat into another room won’t work, since allergens have already made their way into carpets, curtains, and other surfaces. You could create a pet-free room, but it would require never letting kitty in, keeping carpets and similar soft surfaces to a minimum, and changing any bedding or rugs that the cat may have touched.

A more practical option is to manage the allergic person’s symptoms. Over-the-counter allergy medications such as Claritin, Zyrtec, and Allegra don’t stop the allergy but can provide short-term relief from its symptoms without drowsiness. Corticosteroid sprays, available with a prescription, directly treat the inflammatory reaction in allergies. Long says that people prone to allergic asthma attacks should keep a fast-acting rescue inhaler on hand, and if they’re staying in the environment for longer periods of time, they may need a longer-acting treatment.

Long says the allergic person could go on a regimen of allergy shots, “but that’s really a long-term proposition’’ involving weekly visits to an allergy specialist for several months — quite a test of dedication for a new relationship.