Quick answer: side effects from Seraquin are rarely reported. In the 21 Seraquin reviews we read in full, one owner said it upset their dog's stomach and caused wind; nobody mentioned vomiting, diarrhoea or itching. The pack text we could find lists no specific side effects, but Seraquin contains hydrolysed chicken protein and pork liver flavour, and its makers say to check with your vet if your dog takes other medicines. If Seraquin hasn't suited your dog, we'd recommend trying MedPaw Hip & Joint Chews instead, with a 60-day money-back guarantee if it doesn't suit.
Transparency note: this page is written by MedPaw, which makes a competing joint supplement. Reviews are quoted word for word with links so you can check them. Seraquin's label details come from UK retailers, because Seraquin's own website blocked our access. Everything was checked on 8 October 2026.
What Seraquin's label says
Seraquin is a complementary feed, not a medicine, so it doesn't come with a list of side effects like a prescription drug. Here's what the pack information published by UK retailers does say:
- Medication: "If you are considering using Seraquin® along with other medicinal products please consult your vet" (PDSA Pet Store). VetUK and Viovet give the same advice.
- Warnings and contraindications: none listed on the pack text at Ocado or zooplus, beyond keeping fresh water available.
- Pregnancy and nursing: we found no guidance on the pack. A Viovet staff answer says its safety hasn't been tested in pregnant or nursing cats. Ask your vet before giving it to a pregnant or nursing dog.
- Other joint supplements: Viovet advises against giving Seraquin with YuMOVE, because overlapping ingredients could mean giving too much of some.
- Dose: double for the first 4 to 6 weeks, then reduce gradually. Your dog gets the most during that loading phase, so that's when to watch closely.
What owners actually report
Seraquin has few public reviews, so there's little to go on. We read 21 in full on Viovet, VetUK and eBay, dated 2011 to 2023. Only one mentioned a side effect:
Side effects in the Seraquin reviews we read (21 reviews)
| Reported effect | How often | Notes |
|---|---|---|
| Upset stomach and wind | 1 review | The owner said they couldn't use it |
| Diarrhoea or vomiting | None found | |
| Itching or skin reaction | None found | |
| Refusing the tablet | None found in dog reviews | Several owners said their dog takes it easily |
The one report: "Not good on my dogs tummy" (Sandra S., VetUK, February 2020; star ratings aren't shown for individual reviews). She described an upset stomach and wind, and results below what she'd hoped for.
A small, old sample can't tell you how common side effects are. We couldn't read Amazon or Pets at Home reviews, and Seraquin's newer listings have no reviews yet. For the wider picture, see our Seraquin reviews.
Seraquin allergens and ingredients to check
Seraquin doesn't publish an allergen statement. Based on the current ingredient list (glucosamine HCl, sodium chondroitin sulphate, inactivated yeast, maltodextrine, pork liver flavour, turmeric, hydrolysed chicken protein, sodium chloride):
Common allergens in Seraquin Joint Tablets (current pack)
| Allergen | In Seraquin? |
|---|---|
| Chicken | Yes, hydrolysed chicken protein |
| Pork | Yes, pork liver flavour |
| Yeast | Yes, inactivated yeast |
| Fish, krill or mussel | Not listed |
| Shellfish | Not listed, but the source of the glucosamine isn't stated |
| Egg | Not listed |
| Cereals | Not named on the current pack; an older label listed maize protein |
Labels change. VetUK's listing shows an older ingredient list with saccharose, glucose and maize protein, so if your dog has a food allergy, check the box you actually receive.
When to stop and call your vet
- Vomiting or diarrhoea that lasts more than a day, or blood in either
- Your dog goes off their food or becomes lethargic
- Itching, hives, facial swelling or breathing trouble (call straight away)
- Your dog is on other medicines, is diabetic, pregnant or nursing, or has a known food allergy
Any supplement can upset some dogs' stomachs, including ours. For more, read our general guide to joint supplement side effects in dogs.
Why Seraquin customers switch to MedPaw
We'll be straight: MedPaw contains mollusc (green-lipped mussel) and gluten (brewer's yeast), and it's a chicken and bacon flavour chew, so it isn't the answer for every allergy. Where it differs is in how easy it is to give, what's in it and what happens if it doesn't suit.
Seraquin vs MedPaw
| The issue | Seraquin | MedPaw |
|---|---|---|
| If it doesn't suit your dog | No money-back guarantee we could find | 60 days from delivery, for any reason; email us and keep the tub |
| Format | Chewable tablet, often split in half | Soft chew given like a treat; whole chews at every weight |
| Time at double dose | 4 to 6 weeks, then a gradual taper | Three weeks |
| What's in it | Glucosamine, chondroitin, turmeric | All six key joint actives (glucosamine, chondroitin, MSM, green-lipped mussel, hyaluronic acid, Boswellia), with the main amounts per chew on the label |
| Allergens | No allergen statement; contains chicken and pork | Contains mollusc and gluten; not suitable for a shellfish allergy |
Our recommendation: if Seraquin upset your dog's stomach, wasn't easy to give, or you want a guarantee before you try something new, switch to MedPaw, as long as your dog has no shellfish or gluten allergy. Wait until any upset has settled, then start MedPaw. If it doesn't suit, email bark@medpaw.co.uk within 60 days of delivery for a refund. Try MedPaw Hip & Joint Chews.
If nothing has worked so far
If your dog is still stiff or sore after a fair trial of any supplement, see your vet. They may suggest pain relief, weight loss or an omega-3 fish oil at a proper dose, which has the strongest evidence for dogs with arthritis. Read what you can safely give a dog for joint pain and the best fish oil for dogs' joints.
More on Seraquin: what's in Seraquin, MedPaw vs Seraquin and our Seraquin alternatives guide.
Does Seraquin have side effects?
They're rarely reported. In the 21 reviews we read, one owner reported an upset stomach and wind. The pack text we found lists no specific side effects, but advises speaking to your vet if your dog takes other medicines.
Can Seraquin cause diarrhoea?
We didn't find any reviews mentioning diarrhoea, but any supplement can upset some dogs' stomachs. If your dog has diarrhoea for more than a day after starting Seraquin, stop it and speak to your vet.
Does Seraquin contain chicken?
Yes. The current ingredient list includes hydrolysed chicken protein and pork liver flavour. If your dog has a chicken allergy, check with your vet before using it.
Is Seraquin safe with my dog's medication?
Seraquin's pack information says to consult your vet if you're considering using it with other medicinal products, so check with your vet first.
What should I try if Seraquin upset my dog?
Let your dog's stomach settle first and speak to your vet if it doesn't. Then you could try MedPaw Hip & Joint Chews, a soft chew with all six key joint actives and a 60-day money-back guarantee. It contains mollusc and gluten, so it isn't suitable for dogs with a shellfish or gluten allergy.
Can I switch from Seraquin to MedPaw straight away?
Yes, if your dog is well. Stop Seraquin and start MedPaw the next day, and don't give both. If Seraquin upset your dog's stomach, wait until it has settled first. Check with your vet if your dog takes any medication.
