How would you know if your dog was having an allergic reaction to something?

How would you know if your dog was having an allergic reaction to something?

Health & Safety

Both dogs and humans can suffer from allergies, and there are virtually as many different allergens as there are different substances on earth – from pollen to plastics to pet hair and much more. Allergies in dogs are fairly common, and identifying the cause of the allergy, getting the symptoms under control and helping to keep your dog healthy and well can be a challenge if your own dog is allergic to something, and there is no denying that allergies can make your dog quite uncomfortable, and have a measurable impact upon their quality of life.

However, whilst the symptoms of allergies in dogs can make your dog uncomfortable and miserable, causing problems like itchy skin, digestive discomfort, and irritation of the eyes and nose, most allergies are mild enough that they won’t actually pose a threat to your dog’s life.

That said, some allergic reactions in dogs can be very serious and acute and even life-threatening – and this is compounded by the fact that sometimes, the first indication that you will have that your dog is allergic to something is when they display the signs of an acute adverse reaction.

Whether your dog tends to be prone to allergies or if they are apparently very robust and perfectly fine, it is a good idea for all dog owners to know how to recognise the signs of an acute allergic reaction in a dog. Acute allergic reactions can be very fast in onset and even prove fatal if left untreated – and being able to protect your dog depends on knowing how to recognise a serious allergic reaction when you see it, and acting promptly to get them veterinary treatment.

In this article, we will outline the main symptoms of an acute and serious allergic reaction in the dog. Read on to learn more.

Breathing difficulties

A serious allergic reaction can have a systemic effect on your dog’s body, as their body’s immune system mobilises to attack the intruder. A lot of the symptoms of an allergic reaction in the dog will occur internally, which means you have to work with the outward manifestations of the problem to make an informed assessment of what is going on.

Some serious allergic reactions will lead to inflammation of the airways and lungs, which will occlude your dog’s breathing and potentially, place them at risk of hypoxia – not being able to get enough oxygen. Breathing difficulties should be considered to be an emergency (in both humans and dogs) and so if your dog can’t seem to get enough air, is suddenly making laboured breath sounds, is hyperventilating, or is pale or showing signs of blueness in their mucous membranes, they may be undergoing an acute allergic reaction.

Anaphylactic shock

A serious allergic reaction can send your dog’s body into anaphylactic shock, which causes a range of acute and potentially life-threatening symptoms including collapse, loss of bladder and bowel control, and a low, sluggish pulse rate. Anaphylactic shock is a veterinary emergency which usually requires the administration of an adrenaline injection to counteract it, and so recognising this symptom is vital.

Sudden, pronounced swelling

If your dog has an acute allergic reaction to something it may cause pronounced swelling, either across the area of the body affected, or the whole body. This is most likely to occur if your dog is bitten or stung by something that they are allergic to, like a bee – a bad reaction may lead to a sudden, obvious swelling in the area of the bite or sting.

When it comes to biting bugs and insects, dogs often snap at them and so the most common areas of the body to be affected are the face, inside of the mouth, and around the neck – and external swelling may be accompanied by swelling inside of the throat or mouth too, which can result in the breathing difficulties we mentioned earlier on.

Extreme pruritus

Allergies of all types can make your dog feel itchy and uncomfortable, whether that be due to contact with an allergen like pollen, eating a food that they are sensitive to, or touching something that causes them to react badly. This itching will often affect the dog’s whole body, and can often be controlled with antihistamines.

Dogs that suffer from an acute allergic reaction to something might suddenly become very itchy and uncomfortable and show signs of distress as a result of this, frantically rolling or rubbing their skin or gnawing and biting at the itchy areas.

Hives and skin reactions

Localised skin reactions are common in dogs that suffer an allergic reaction to something they have come into contact with, which might produce obvious visible symptoms as well as extreme itching.

Skin that looks red and irritable, inflamed, or that shows signs of a rash might indicate an allergic reaction, and in the case of an acute allergic reaction, your dog might develop hives – raised lumps or bumps that come up suddenly under the skin.

Acute digestive upset

Most dogs that are allergic to a certain food substance will suffer from some level of digestive discomfort and/or upset if they eat it, such as a stomach ache, loose stools, diarrhoea or vomiting.

However, if your dog has an acute allergic reaction to something that they eat, these symptoms may well be sudden and very pronounced – and may include almost immediate and powerful vomiting, loss of bowel control or sudden diarrhoea, and acute stomach cramps and pain, which all warrant a trip to the vet.



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