Health
Rotten fish on the cushion, a doggy smell two days after a bath, a pug scooting across the carpet. The smell has about six possible sources and each needs its own fix.
Caution. A painful red-purple swelling beside the anus, a hole oozing pus, a dog who will not sit, a smell of rotting meat from a damp patch of coat (maggots: now), or a smell with fever and lethargy: see your own vet today.
Do not look for the answer in a Facebook group, on TikTok or on a forum. Look for someone trained for this: your dog's own veterinarian, the only person who can examine, investigate and treat them.
Use this page to know what to observe, what to note and what to ask at the appointment, not to treat at home. If you still have doubts after a consultation, ask another vet or a specialist (dermatologist, internist) for a second opinion, not a group. And if you do not have a regular vet yet, find one now, while your dog is healthy: how to choose a veterinary clinic.
Your dog gets up off the sofa and leaves behind a damp brown mark on the cushion and a smell of rotten fish. Or you have a cocker who smells "doggy" two days after a bath, whatever shampoo you try. Or a pug who drags his bottom across the living room carpet and keeps licking under his tail. A smell is telling you something, and on a dog it can come from about six places: the mouth, the ears, the skin, the paws, under the tail and the other end of the digestive system, as wind. Below is how to track down the source with your own nose, what anal glands are (the culprit everyone searches for) and what your own vet can do about each source. You will not find instructions for emptying the glands at home. Done at home, it usually does more harm than good.
The smell itself is not an emergency. What lies behind it sometimes is. Ring today if:
For everything else, book an appointment this week, with the source already found.
Find the place first. Sniff your dog section by section, the way a vet would: the mouth, each ear, the skin on the back and the belly, the folds (the face in flat-faced breeds, the base of the tail, around the vulva in overweight bitches), between the pads, under the tail. Note where it is strongest.
When it smells. All the time? Only after a fright or a lot of excitement (the anal glands empty by themselves when he is worked up)? After lying down, after a bath (the "wet dog" smell that will not leave), after a meal (wind)?
Marks. A yellow-brown oily mark on a cushion or the bed that smells of fish is anal gland secretion. A damp one without much smell is urine, usually an older spayed bitch leaking in her sleep.
What he does with his rear end. Scooting (how many times a day?), licking or nibbling under the tail, whipping round towards his tail as if something bit him, sitting down carefully.
Faeces. Soft for a few days, or always soft: a stool with no substance does not press on the glands on the way out, so they do not empty. Recent diarrhoea irritates the area and causes scooting too.
Ears. The smell (sweet and rancid, like old cheese, means yeast; like pus, bacteria), the colour of any discharge (dark brown like coffee grounds, yellow, black), whether he shakes his head, scratches, flinches when touched.
Skin and coat. Red, damp, hairless patches (a "hot spot" can appear within hours and smells bad), scabs, a greasy coat, dandruff, dark thickened skin in the folds. Where he scratches and how much.
Paws. A faint smell of corn snacks on the paws is normal; it comes from bacteria that live naturally between the pads. Red, damp paws that he licks constantly and that smell strongly are a different story.
Mouth. Lift the lip and look for tartar, red gums, a broken tooth. A fishy smell that seems to come from the mouth often comes from under the tail: he has been licking there.
What has changed. New food, scraps from the table, fewer walks, extra weight (overweight dogs have more trouble with both glands and skin folds), a new shampoo, more frequent baths, swimming in a lake.
| Smell | Source | What else you see |
|---|---|---|
| Rotten fish, metallic, sudden, after a fright or after lying down | Anal glands | Oily mark on the cushion, licking under the tail, scooting |
| Rotten fish all the time, pain when sitting | Long-full anal gland, infected, abscess | Swelling beside the anus, will not sit, yelps |
| Sweet and rancid, old cheese, yeasty | Ears, folds, paws | Brown discharge, head shaking, red greasy skin, itching |
| Pus | Infected ear, wound, abscess, "hot spot" | Yellow discharge, pain, moist redness |
| Wet dog that does not go once he is dry | Skin: seborrhoea, infection, sometimes an underactive thyroid | Greasy or dry coat, dandruff, smell back a day after a bath |
| Rotten, from the mouth | Teeth and gums; occasionally something wedged | Tartar, red gums, drooling, chewing on one side |
| Sweet or like pear drops, from the mouth | Diabetes | Drinking and weeing a lot, losing weight |
| Ammonia, urine | Kidneys, or urine on the coat | Drinking a lot, vomiting, flat; damp patch in the bed |
| Rotting meat, from a damp area | Infected wound, maggots | Larvae, matted coat, dog subdued |
| Wind | Food, eating too fast, the gut | Rumbling belly, soft stools |
Two pairs get mixed up all the time. Anal glands get mistaken for the mouth, because after a lick the smell moves. And bad skin gets passed off as "the breed smell". A breed does not smell. Unhealthy skin does.
Two little sacs, anywhere from pea-sized to hazelnut-sized, one each side of the anus, at roughly four o'clock and eight o'clock if you picture it as a clock face. They make an oily, brownish, strong-smelling liquid that marks the faeces: the dog's calling card for other dogs. Normally they empty by themselves, a little at a time, when a firm stool passes and presses on them. If the stools are soft, if the glands sit deeper (common in small breeds) or if the dog is overweight, they stop emptying. They fill, the secretion thickens to a paste, they press and itch, and the dog scoots and licks. From there to infection and an abscess is not far. A healthy dog with normal stools never needs anyone to empty them.
Firm stools come before anything else; your vet may suggest more fibre or a more suitable food. Weight brought back to normal. Regular walks, because moving helps digestion. A diary of the days he scoots or licks, so you can see how long passes between episodes and whether the gap is getting longer. Go back to the vet when the gap drops below a few weeks. Surgery only comes up once everything else has been tried for a few months.
On a training day, a dog who empties his glands from excitement can be smelled from three metres away, and everyone grins. At home on the cushion, you grin rather less. A smell is easy to read if you go looking for it with your nose before covering it with perfume. If you do not have a regular vet yet, our page on related services will help you choose a practice.
What dog owners search for most often on the internet about this problem, with the short answer. The answers are a guide only: the decision belongs to your dog's own vet, after an examination.
In a healthy dog with firm stools, never: they empty by themselves, a little at a time, with every stool. Your vet empties them only in dogs who scoot, lick under the tail or have full glands at a check-up, when the signs appear rather than on a schedule. Expressed routinely at every grooming, they get irritated and fill faster.
We would not recommend it. From outside they only half empty, it hurts, and an inflamed gland can burst under your fingers; you also cannot feel whether there is a lump or tell if what comes out is pus. Your vet empties them by rectal exam, completely and in seconds, and sees what comes out. If the problem keeps returning, the conversation moves to stools, weight and allergies.
Because his anal glands have emptied: after a fright, a burst of excitement or simply when he got up off the cushion, leaving an oily brown mark. Once in a while, that is normal. If the smell is constant, or he scoots or licks under his tail, the glands are full or inflamed and need seeing by your vet. A fishy smell that seems to come from his mouth usually starts there too.
Because the source is under the coat and the shampoo does not reach it: yeasty ears, greasy inflamed skin, damp folds, full anal glands or tartar on the teeth. Frequent bathing makes the skin worse, and the smell is back in two days. Sniff him section by section, find the spot and take that answer to your own vet. A healthy dog does not smell strongly a week after a bath.
Less often than people think. Full or irritated anal glands are the most common cause, then soreness after diarrhoea, allergic itching, and only then tapeworm (white segments like grains of rice near the tail). Check his stools and under his tail, note how many times a day he scoots and take him to the vet: a rectal exam and a stool test sort it out in ten minutes.
The information on this page is educational and does not replace an examination. For full details and a diagnosis, consult your dog's own veterinarian.
They often come together: the same causes, plans that complement each other.
He plonks himself down and drags across the carpet, licks under his tail, leaves a fishy smell. Most often it's the anal glands, but not always.
A brown crust on the back teeth, a red line along the gum, breath you smell from across the sofa. Lift the lip to see the mouth; under the gum, only the vet sees.
Head shaking, scratching until he yelps, a yeasty smell. The ear is where it shows, the cause is usually elsewhere, and last time's drops will not find it.
Claws on the belly at midnight, paws licked red, an ear infection every summer. Behind the word "allergy" sit at least three diseases, each with its own plan.
We work with your dog's behaviour, not its health. For any sign described here, book an appointment with your own vet; the related services page explains how to choose a clinic.