Why does my dog itch so much, when he has no fleas? My dog is constantly scratching and biting himself – how can I help him? My dog is itching all of a sudden, and I don’t know what to do!
And – maybe most common of all – how do I get my dog to stop chewing his paws?
These are all super common questions I face as a veterinary surgeon. Perhaps a quick google search has lead you to mistakenly believe this is boredom, or habit (TLDR: it isn’t. He’s itchy as all hell).
Maybe your dog breaks out in a rash on his belly and inner thighs after a walk, or appears red and sore around the eyes or muzzle?
Or perhaps you’re wondering why your dog keeps getting ear infection after ear infection (note – ear infections are very relevant to the topic of allergies in dogs, as will become clear throughout this article).
An excessively itchy dog is one of THE most common complaints I see on a daily basis as a GP vet, and honestly the ten minutes I have in the consult room to discuss this topic with pet owners is nowhere near enough time to explain the underlying causes of excessive itching in dogs and, more importantly, what can be done about it.
But here, I have the time to be thorough. And you can benefit from my years of experience in treating itchy dogs, and – the holy grail – you might just find a permanent solution to your dog’s struggles with itchy skin.
Let’s dive in.
There are a number of possible reasons. This article focuses on Canine Atopic Dermatitis (CAD), which I estimate accounts for about 90% of the itchy dogs I see in practice on a daily basis.
But before we make our presumed diagnosis of atopic dermatitis, we must first rule out a couple of others:
1. When did you last flea treat your dog?
…And did you use a product that also kills the parasites you can’t see such as ear mites, demodex and other skin mites? If you’re not sure, then definitely tick this box first, without delay.
2. Could this be contact dermatitis?
…That is, an itchy allergic reaction to direct contact with something irritating such as a new shampoo or doggy cologne, a flea spot-on, or a household cleaning product? If this is a possibility, start by rinsing your pet thoroughly in the shower (just using lukewarm water – no shampoos needed), and then towel dry.
3. Could this be a food allergy?
Really, food allergies deserve their own blog post, and don’t worry – this is on my list…but for now, the key thing to know is that (contrary to common misconceptions) it is the meat proteins in food that dogs tend to be allergic to, and rarely things like wheat or grains. Where an allergy is responsible for a dog’s excessive itching, it is actually only food related in around 10% of cases – maybe less. A food allergy is more likely if the itching started when the pet was less than one year old, especially if they were 6-8 months old when the itching began.
So, before we make the diagnosis of atopic dermatitis, we must first carry out a strict, 12+ week hypoallergenic or anallergenic diet trial to confirm whether the itching could be a food allergy.
If the above have been excluded, then it’s time to strongly consider the possibility that this could be atopic dermatitis.
As a vet, I use the Modified Favrot’s Criteria to help me make this diagnosis. If your dog meets five or more of the following criteria, then CAD is likely:
- Excessive itching started when your dog was less than 3 years old
- Your dog lives mostly indoors (ie, in a house, not in an outdoor kennel)
- The itching is steroid-responsive (meaning if your vet prescribes a short course of steroids such as prednisolone, the itching goes away)
- Your dog is prone to yeast overgrowth (between the toes and in the ears. Signs include yeasty-smelling feet and ears, brown wax in the ears, moist spaces between the toes, and – of course – an increase in itchyness)
- Your dog’s front feet are affected (ie, itchy)
- Your dog’s ear pinnae are affected. The pinna is the pointy or flappy (depending on your dog) part of the ear. The margins of the pinna are usually not affected.
- Your dog’s back is not affected (rather, itching tends to be around the face, ears, armpits, groin, stomach and feet)
Sounds like your dog?
I thought it might.
OK, so what do we do about it? How can we help him/her (and you) get some relief?
1. Make sure you are rinsing or hosing off your dog’s feet when you come in from every walk
When I’ve run allergy bloods on dogs, the most common offenders are always grasses (such as Timothy and Rye grass), weeds (such as ragwort and dandelion), trees (such as beech), fungal spores and yeast. Physically removing the microscopic allergen particles from your dog’s skin can make a big difference to their itch level. Even better, use malaseb or malabeze shampoo, or CLX wipes, as these have anti-yeast properties.
Be aware that correct use of malaseb and malabeze shampoos involve leaving the lathered (foamy) shampoo in contact with the skin for 5-10 minutes before rinsing. Yes, I know it’s a pain to have Rex slipping and sliding around the bathroom floor all soapy and wet. But you’re wasting your money if you rinse if off without waiting the full prescribed time.
2. Trial an antihistamine
Now I’ll be honest (as always); piriton only seems to work for about 1 in every 3 or 4 dogs. They don’t metabolise it the exact same way we do, and it’s simply less effective.
That said, it’s a very safe drug (with occasional use, at worst you might see some drowsiness), cheap, and easily available. I typically prescribe it at the following doses:
2mg twice daily for dogs <5kg / 10lb
4mg once or twice daily for dogs 5-15kg / 10-33lb
4mg up to three times daily for dogs 15-25kg / 33-55lb
8mg twice daily for dogs 25+kg / 55lb+
Up to 8mg three times daily for dogs 40g + /88lb +
Piriton is sold as 4mg tablets (in the UK at least). And ‘Piriton’ is actually just a brand name – the active ingredient is chlorpheniramine maleate.
I usually advise owners to follow these dosing guidelines for a week before deciding whether the piriton is or isn’t working for their pet.
If your trial is successful and you want your dog to continue on piriton long-term, I advise you to book a consult with your vet. I have never yet encountered a dog for whom I felt piriton wasn’t a safe option, BUT there will be exceptions to this, especially when it comes to elderly pets or pets who are already on certain medications.
3. Keep your dog’s ears clean
Because atopic dogs are very prone to ear infections. Allergies are, after all, a skin barrier issue just as much as they are an immune system issue. And if you have a bunch of yeast in your ears and are hypersensitive (allergic) to yeast, that’s gonna be very itchy!
I recommend using malacetic (you can buy this on Amazon), cleanaural or epiotic to clean your dog’s ears at least twice weekly. You can also apply Peptivet Otogel post-cleaning to help prevent ear infections.
By the way, none of these companies pay me and nor am I affiliated with any of them.
They just work.
Be aware that liquid ear cleaners can cause real problems if your dog has a ruptured ear drum; so never use a liquid ear cleaner on a dog displaying a head tilt, signs of deafness or with very red/inflamed or painful ears. Take him or her to the vet instead.
4. Use a barrier method (ie, the cone of shame)
I literally only recommend this as a short-term measure to stop your dog causing damage to their own skin by excessive licking and scratching, whilst you wait for an appointment with your vet.
Applying a barrier method without addressing the underlying itching itself, is just cruel.
Image for a second being on holiday, and being covered from head to toe in mosquito bites… and not being able to scratch them, apply cream, take meds or do anything at all about it! Torture!
5. Add a good quality Omega 3 supplement to your dog’s daily diet
For example, YuDerm Itchy Dog (again, they aren’t paying me, it just works).
Salmon oil will also help.
Steer clear of feeding actual oily fish (such as sardines, or tuna canned in sunflower oil) more than once a week, due to the risk of heavy metal accumulation. This is especially true of large fish such as tuna; I have absolutely seen dogs and cats who have been fed tuna in sunflower oil on a daily basis for their skin, go on to develop kidney failure which I believe was likely linked to this excessive and unsafe intake of tuna, which we know contains heavy metals.
Be aware! – Nobody online can give you a fits-all-sizes salmon oil dose, because different salmon oil brands and formulations will contain different levels of EPA/DHA.
I typically recommend 80mg/kg (that’s 36mg/lb) total EPA/DHA per day.
Also be aware that it is absolutely possible to overdose on Omega 3, so please don’t go above this limit. It won’t work better, and it could lead to vomiting, diarrhoea, blood clotting problems, and altered immune system function.
This was the kind of salmon oil supplementation Daisy could really get behind
6. Finally – See your vet to discuss allergy medications
I know it can be hard to stomach (not least because it can get so expensive, but also because we don’t like to medicate our babies), but some dogs just need allergy medication on a daily basis, either year-round or seasonally, to be able to live a happy, itch-free life, and to prevent recurrent ear infections.
Luckily we do have some exceptionally safe and effective options for allergy medications these days, so by no means is it still the case that we have to rely on harmful long-term steroid use.
I don’t for a second believe in over-medicating our pets, however, I also can’t think of much worse than being itchy every second of the day. It affects your dog’s sleep, rest and quality of life, and we are here to help, so please use us! I’m not here to con you into buying bog water marketed as a miracle cure. I just want your dog (and you) to get a good night’s sleep.
What would you like to check out next??:
- Why is My Dog Dry Heaving?
- Top 5 Best Calming Treats for Dogs
- Is there an Alternative to Apoquel for Dogs?
- Can Dogs Eat Raw Chicken – And Raw Chicken Bones?
- When To Euthanize A Cat With IBD
Know somebody with an itchy dog? Send ’em this:
For more information, I recommend the following resource for pet owners:
https://spvs.org.uk/wp-content/uploads/2019/01/Canis-Atopy-Owner-Factsheet.pdf
Whereas the following resource is perhaps more appropriate for vets (and anybody else with a medical background, eg students, nurses):
https://vetfocus.royalcanin.com/en/scientific/canine-atopic-dermatitis-and-the-owner
Feel free to pop any questions in the comments!
xx Daisy
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