Over the Counter Allergy Medication for Dogs

Over the counter allergy medication can have a place in helping to relieve your dog's symptoms. They may be used as standalone treatments, or they may be used in conjunction with other treatments such as steroids or immunotherapy that your veterinarian may recommend. 


When your dog has an allergy attack, his immune system creates a chemical called histamine to fight the invading allergens and defend his body against further attack. Histamine causes skin irritation, hives and inflammation. In severe instances, it can cause anaphylactic shock, which can be deadly if left untreated.

Antihistamines help reduce histamine levels so that these symptoms can be controlled and your dog can feel better. They can be used to alleviate life-threatening symptoms such as airway constriction in cases of serious allergy attacks, or they can relieve itching and inflammation in less severe attacks. They can help relieve symptoms caused by flea allergies, food allergies and atopic allergies.

Common over the counter allergy medication in this class includes chlorpheniramine (Chlor-Trimeton), clemastine (Tavist), diphenhydramine (Benadryl), hydroxyzine (Atarax) and loratadine (Claritin). Common side effects of antihistamines include drowsiness, dry mouth, lethargy and loss of appetite.

If your dog has difficulty swallowing pills, special treats are available from your pet supply store. They feature a pocket that will allow your dog to consume the pill while enjoying the treat.

When giving antihistamines to your dog, be sure to give him the basic form of the drug, and not a version that has added decongestant or pain-relief medication. These can be dangerous to your pet's health.

Topical Products

Topical products such as foams, lotions, mists, rinses, shampoos and sprays are another over the counter allergy medication that can help relieve a dog's skin symptoms. They are effective at easing symptoms of flea, food or atopic allergies. Many of these topical products contain hydrocortisone, which helps alleviate itchiness.

Oatmeal is also found in many topical products, and it was recognized by the ancient Egyptians and Romans for its ability to soothe damaged skin. Some products use tea tree oil, probiotics and other natural ingredients to reduce itching and promote skin healing.

Dietary Supplements

Dietary supplements, such as fish oil, flaxseed oil or biotin, also have a role to play in canine allergy relief. Adding these liquid or powdered supplements to your dog's food each day can help his skin heal. However, they are not a short-term solution to your dog's allergy problem because he needs to take them for several weeks before symptoms begin to improve. Supplements can help alleviate symptoms of flea, food or atopic allergies.

Other canine allergy-control supplements can be purchased at your local pet supply store. They are available in liquid or tablet form and can help relieve many allergy symptoms, such as sneezing, itchy skin, or a runny nose.

Before giving your dog any over-the-counter allergy treatment, discuss dosage instructions with your veterinarian to ensure the new medication won't interfere with your dog's overall good health.