Decongestant/Antihistamine Products for Pets

Do you know the difference between a decongestant and an antihistamine, and when to give them to your cat or dog? Both decongestants and antihistamines can be helpful in relieving your pet’s allergy symptoms, but they aren’t always used interchangeably. Let’s look at what each type of medication does and under what circumstances you should give them to your pet.

Antihistamines Take the Itch Out of Allergies

Your pet’s allergy attack begins when his immune system begins producing histamine, a chemical that helps fight off a perceived threat to your pet’s health. This threat, which is also known as an allergen, triggers the allergy attack, and your pet’s symptoms appear soon afterward. They can include itching, rashes and hives, but they can also include sneezing and wheezing.

Antihistamines counteract the effects of histamine to reduce the symptoms of an allergy attack. They are useful in treating food, flea and atopic allergies because they can relieve a variety of symptoms, including stopping itching, easing breathing and reducing swelling and redness.

One of the long-standing problems with antihistamines were their side effects. Common side effects of older antihistamines included appetite loss, drowsiness, dry mouth or hyperactivity. Newer types of antihistamines do not usually cause drowsiness, which makes them a useful tool to help your allergic pet.

Decongestants Help Relieve Congested Noses

When your pet has an allergy attack, his nasal tissues swell, and his nose produces more mucus. This increased mucus production causes nasal congestion, and your dog or cat may have trouble breathing.

As their name suggests, decongestants reduce congestion or swelling, especially in the nasal passages. They do this by reducing blood flow to the affected area, which helps bring down swelling and makes breathing easier. They are effective at relieving stuffy noses and clearing nasal passages.

Some pets receive congestion relief with the use of steam or saline solution sprayed in the nose. Consider placing your congested pet in your bathroom with the shower running or spraying his nose with saline nasal spray to help him feel better until he can be evaluated by your veterinarian.

When to Use Over-the-Counter Medications on Your Pet

Some over-the-counter allergy medications for people can be safely used on your cat or dog as long as you follow your veterinarian’s instructions on dosing exactly. Antihistamines that are safe for pet use include:

  • Atarax (hydroxyzine)
  • Benadryl (diphenhydramine)
  • Chlor-Trimeton (chlorpheniramine)
  • Periactin (cyproheptadine)
  • Tavist (clemastine fumarate)
  • Zyrtec (cetirizine)

When purchasing antihistamine products for pet use, make sure to purchase the allergy-only form of the drug because some of them are sold in an allergy-decongestant combination that can be unsafe for use in pets.

Discuss the use of over-the-counter human decongestants with your veterinarian. Some are safe for use in dogs under veterinary supervision, but most are not safe to use on cats.

What to Do if Your Pet Takes Too Much Medication

If you suspect your pet has overdosed on antihistamines or decongestants, you will need to seek emergency veterinary care immediately. Symptoms of medication overdose include

  • breathing problems
  • changes in heart rate
  • confusion
  • depression
  • hyperactivity
  • seizures
  • tremors
  • vomiting

If your pet is conscious, try to induce vomiting before taking him to your veterinarian’s office or emergency animal hospital.