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In this lesson, you'll be learning about allergies, including both long-standing allergies and those that come on suddenly. We'll provide you with some signs and symptoms for each type and tell you when it's appropriate to see a veterinarian for every situation.

Allergies are a sign that your pet's body is overreacting to an exposure to some type of foreign substance. There are two types of allergies – sudden onset allergies and long-standing allergies.

  1. Sudden onset allergies, as the name implies, are those that come on suddenly. Sudden onset allergies are typically caused by things like:
    a. Insect stings
    b. Medications
    c. Vaccinations
  2. Long-standing allergies, by contrast, do not usually come on suddenly but develop over time. Long-standing allergies are typically caused by things like:
    a. Different foods
    b. Environmental allergies like grass or pollens

Sudden Onset Allergies

If your pet is experiencing a mild yet sudden allergic reaction, the signs you will usually see include:

  • Pain
  • Facial swelling
  • Scratching
  • Hives – red raised bumps on the skin
  • Vomiting

If you see any of these signs in your dog or cat, it's time to check those vital signs. What you discover will determine your next course of action.

If Your Pet's Vital Signs are Normal

If you've checked your pet's vitals and they all appear normal, you can contact your vet for some advice. He or she may recommend you give your pet some over-the-counter diphenhydramine, also known by the brand name Benadryl. However, your veterinarian may recommend you bring your pet in for an evaluation.

Pro Tip #1: If your vet does recommend giving your pet Benadryl over the counter, you should monitor your pet closely afterward. If at any time her symptoms get worse or if her signs are not improving after 30 to 60 minutes, you'll need to take her in for a veterinary evaluation right away.

If Your Pet's Vital Signs are Abnormal

Let's say you check your pet's vitals and notice some abnormalities. This can be a sign of a worse condition or greater problem. in situations like these, it's important to be aware of a condition called severe anaphylaxis shock, as it can be life-threatening.

In particular, if you notice the following signs of anaphylaxis shock, this may be a real cause for concern:

  • Light pink or dark red gums
  • A fast pulse rate
  • A fast breathing rate
  • Weakness
  • Collapse

Warning: This could be very serious. If you notice any of these signs, transport your pet to a veterinarian facility as soon as possible. And DO NOT give your pet any medications unless first instructed by your vet.

Long-Standing Allergies

Dogs and cats, like people, can develop long-standing allergies to things like food and other environmental allergens. If your pet is suffering from this type of allergy, signs you might see include the following:

  • Hair loss
  • Reddened skin
  • Raised bumps on the skin, like papules or pimples

If you notice any of these signs, you'll want to make an appointment to talk to your veterinarian about long-term treatment options. However, even with treatments, flare-ups can still occur. When a flare-up does occur, it can cause moist and reddened skin that can be intensely itchy.

Pro Tip #2: If your pet has long-standing allergies and suffers from a flare-up, it's important to limit your pet's ability to scratch, lick, or chew those affected areas on her body, as this can cause or spread secondary bacterial infections.

How do you keep your pet from doing any of the above? Well, the two best ways to do this are using an E-collar or a cone. Surely you've seen these cones before. They're perfect for preventing your pet from the chewing and licking that will likely just cause more problems. And if you haven't had a pet need one of these cones before, beware that she will not like wearing it.

If you do put a cone or E-collar on your pet, keep it on until you can get seen by your veterinarian and until you can get your pet's long-standing allergic reaction or flare-up under control. Better your pet has a bruised ego or feels uncomfortable for a few days than contracting a bacterial infection.