First-generation antihistamines most of these antihistamines are available without a prescription, such as diphenhydramine (Benadryl), clemastine (Tavist), and chlorpheniramine (Chlor-Trimeton Allergy). These older antihistamines are more likely to cause drowsiness. Depending on the product, the duration of action is often shorter than newer antihistamines and may necessitate taking the drug 3-4 times each day. These older antihistamines are more likely to cause dry mouth, urinary retention, constipation, and blurred vision.



Second-generation antihistamines are also referred to as nonsedating antihistamines. Most are only available by prescription, such as cetirizine (Zyrtec), desloratadine (Clarinex), and fexofenadine (Allergra).

The original second-generation antihistamines are now becoming available without a prescription (over the counter [OTC]), such as loratadine (Claritin). They can be taken over the long term with minimal side effects and are unlikely to cause sleepiness. The nonsedating antihistamines are convenient to take since they are taken once or twice daily. They may allow you to carry on with your normal activities more easily than older first-generation antihistamines.

Allergy shots are given to some people who have persistent and disruptive allergy symptoms. The shots do not treat symptoms, but by altering the immune response, they prevent future allergic reactions. This is referred to as allergen immunotherapy. Treatment involves a series of shots, each containing a slightly greater amount of the allergen(s) that cause the reaction. Ideally, the person will become desensitized to the antigen(s) over time.

If your symptoms are severe enough or last long enough to require treatment by a medical professional, follow his or her treatment recommendations. Take all prescribed medications as directed.

The single best thing you can do to stop the reaction is to reduce your exposure to the allergens. If it is animal dander causing your allergic reaction, you do have options. If you decide to keep the pet and live with your allergy, have as little direct contact with the pet as possible.

Before getting a pet, spend indoor and outdoor time with other animals of the same species to make sure all family members can tolerate the dander. Remember that allergies tend to run in families. If you are allergic to animal dander, your children may be too. Also, even people who do not have problems initially may develop them later. It is practically impossible to remove all house dust with all its allergens from your home