Guinea pig seizures: what to do during the episode and what causes them

Quick answer

A guinea pig that suddenly collapses, thrashes, screams or goes rigid is frightening to watch, and the first job is to do very little. Do not pick it up, do not hold it down, and do not put anything near its mouth. Clear hard objects away, dim the light, note the time, and film it if you can.

The second job matters just as much: work out what it actually was. A large share of episodes that owners describe as seizures in guinea pigs are not seizures at all. The single most commonly missed cause is a skin mite that produces pain so intense the animal convulses, and it is completely treatable once identified.

During an episode, the useful actions are removing hazards, reducing light and noise, and timing it. Handling makes it worse.

• Never restrain a guinea pig during an episode, and never put fingers or objects in its mouth.
• Screaming and thrashing with apparently normal skin is the signature of a burrowing mange mite, not of epilepsy.
• Every episode needs a vet, and a skin scrape should be part of that appointment even if the coat looks fine.
• Afterwards, the priority is getting the guinea pig eating again. A gut that stops moving becomes a second emergency within a day.
• Never use dog or cat parasite products on a guinea pig, and never give human medication of any kind.

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A guinea pig that has stopped eating after an episode is in a second emergency.

Guinea pigs need continuous fibre moving through the gut. Pain, stress and post-seizure disorientation all stop them eating, and a gut that stops moving is fatal within a short number of days. Once the animal is fully alert, offer its favourite fresh food and hay immediately, watch that it is actually chewing and swallowing, and contact a vet the same day if it will not eat. Do not wait until the next morning to see whether appetite returns.
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Decide in 60 seconds

What to do while it is happening

Do not pick the animal up. Handling during a seizure increases the risk of injury to the guinea pig and of a bite to you, and it does nothing to shorten the episode.

Do not restrain it. Holding a convulsing animal still can cause limb and spinal injury.

Do not put anything in the mouth. Guinea pigs do not swallow their tongues. Fingers and objects near the mouth get bitten and can damage the teeth.

Clear the space. Move water bottles, ceramic bowls, hard hides and anything with edges away. If the animal is on a raised surface, block the edges so it cannot fall.

Reduce the input. Dim the lights, turn off the television, and ask others to be quiet. Sensory stimulation prolongs episodes in many animals.

Note the time. How long it lasts is one of the most useful pieces of information a vet can have, and everyone overestimates it. Look at a clock rather than guessing.

Film it if you can do so without disturbing the animal. A video removes almost all the guesswork about whether this was a seizure, a pain response or something else.

Afterwards, keep it warm and quiet. Disorientation is normal after a real seizure and can last a while. Leave the animal somewhere dark, warm and enclosed with familiar bedding.

Then get it eating. Once it is fully alert and swallowing normally, offer its favourite greens and fresh hay. This is not a comfort measure; it is the thing that prevents the next problem.

Why the mite matters so much

The single most important differential in a guinea pig with convulsive episodes is a burrowing mange mite that lives within the skin.

The mechanism is straightforward and brutal. The mite tunnels in the outer layers of the skin, and the reaction to it produces intense itching and genuine pain. Affected guinea pigs run frantically, scream, thrash, and can have episodes indistinguishable from a seizure to anyone watching.

The reason it is missed is that the skin can look almost normal early on. Owners reasonably conclude that a problem with no visible skin lesion cannot be a skin problem. Later the picture becomes obvious, with hair loss and crusting along the back, the flanks and the inner thighs, thickened skin, and areas the animal has scratched raw.

Two things make this worth knowing. First, it is common. Second, it is treatable, and treatment produces a dramatic change in an animal that had been having repeated episodes.

The practical consequence is that a skin scrape belongs in the first appointment for any guinea pig with convulsive episodes, whether or not the coat looks abnormal. Ask for it specifically if it is not offered.

Stress and illness make an existing mite population flare, which is why episodes often begin after a move, a new companion, a change of housing or another illness.

A full examination includes the mouth, the ears and the skin. Guinea pig molars cannot be assessed by looking at the front teeth.

The rest of the differential list

Heat.

Guinea pigs are poor at losing heat. They cannot sweat effectively, their coat is dense, and a hutch in sunlight, a conservatory or a car becomes lethal quickly. Heat collapse presents as an animal splayed flat, drooling, breathing rapidly, weak, and sometimes convulsing. Cooling must be gradual, with cool surfaces and airflow rather than immersion in cold water, and it is an immediate emergency.

Late pregnancy and the period just after.

A sow in the last weeks of pregnancy, particularly one that is overweight, that has been stressed, or that has gone off food, can suffer a metabolic collapse. It presents as sudden dullness, weakness and sometimes convulsions in an animal that seemed fine. It is life threatening and it needs immediate veterinary care. Any pregnant sow that goes off her food is an emergency rather than a wait-and-see.

Vitamin C deficiency.

Guinea pigs cannot synthesise vitamin C and depend entirely on the diet. Deficiency causes painful joints, reluctance to move, weakness and bleeding. It rarely produces a true seizure but it produces an animal that squeals when handled and moves oddly, which gets reported as one.

Ear and vestibular disease.

A head tilt, circling in one direction, or rolling is a balance problem rather than a seizure, and the animal usually remains aware of you throughout. It needs investigation of the ears and the nervous system.

Low blood sugar in an animal that has stopped eating.

A guinea pig in gut stasis that has not eaten for a while can become weak and collapse.

Toxins.

Insecticides, pesticides used in the home or garden, and flea treatments intended for dogs and cats are all realistic causes. Several products that are routine in larger pets are dangerous or fatal in guinea pigs. If any product has been used on or near the animal, take the packaging to the vet.

Head injury.

A fall from a height, being dropped, or being trodden on. Guinea pigs are dropped more often than owners admit, and a head injury can produce seizures hours later.

Genuine idiopathic epilepsy.

It exists, and it is a diagnosis reached after excluding the treatable causes above rather than one made on the appearance of the episode.

Telling normal behaviour apart

Popcorning.

A healthy, happy guinea pig jumps straight up, twists in the air, sometimes runs a short burst and repeats it. It happens most in young animals, at feeding time and after a clean, and the animal is fully aware and interacting with you throughout. It is a sign of a guinea pig feeling well. It is also, reliably, the thing new owners phone about.

Shivering.

Guinea pigs shiver when cold, when wet, and sometimes when frightened. The animal remains upright, aware, and stops when the cause is removed.

Stretching and yawning.

Normal, and occasionally dramatic in appearance.

Startle response.

A sudden freeze followed by a scattering run is normal prey behaviour, not a neurological sign.

The distinguishing feature in all of these is awareness. A guinea pig that responds to your voice, turns to look at you, and can move purposefully is not having a seizure.

After an episode, the goal is a warm, dark, quiet space with familiar bedding, water within reach and hay the animal can start eating as soon as it is alert.

What the appointment should cover

Expect a full physical examination including body weight, temperature, the ears, and the mouth. Guinea pig molars grow continuously and cannot be assessed by looking at the incisors, so a proper oral examination requires an instrument and sometimes sedation.

Ask specifically for a skin scrape, in more than one site, even if the skin looks normal.

Expect questions about whether the animal is pregnant or has been housed with a boar, about heat exposure, about diet and vitamin C, and about every product used in the home and on other pets.

Blood tests may be used to look at blood sugar, calcium and organ function.

Bring the video. It is the most valuable single item, because a vet cannot reproduce the episode in the consulting room and descriptions of animal seizures are notoriously unreliable.

Bring the weight record, and expect the vet to weigh the animal at every visit.

What never to do

Do not hold, restrain or pick up a guinea pig during an episode.

Do not put fingers, spoons or anything else near or in the mouth.

Do not give food or water until the animal is fully alert and swallowing normally.

Do not give human medication, including painkillers, antihistamines or anything intended for seizures.

Do not use dog or cat flea or mite products on a guinea pig.

Do not put a collapsed, overheated guinea pig into cold water.

Do not treat a suspected skin problem with a shop-bought spray instead of getting a diagnosis.

Do not assume a single episode was a one-off. First episodes are how treatable conditions announce themselves.

Do not delay if the animal is not eating afterwards.

When to get help

Go immediately for an episode lasting more than a couple of minutes, repeated episodes without full recovery in between, collapse in warm weather, a pregnant sow that is dull or off food, known contact with an insecticide, or a guinea pig that is unresponsive.

Keep a carrier lined with a towel, and a bag of the animal's own hay, ready to go. A guinea pig travels better with something that smells of home.

Book the same day for any first episode, for repeated screaming or frantic scratching, for a head tilt or circling, and for any guinea pig that has not eaten since the episode.

Bring the video, the timed duration, the weight record, the full diet including how vitamin C is provided, the housing and recent temperatures, whether there has been a recent change or a new companion, whether the animal could be pregnant, and the packaging of any product used on any pet in the household. Ask for a skin scrape as part of the examination, and ask what the follow-up plan is if the first tests are negative.