Guinea pigs, hamsters and rats: is this an emergency?

Small bodies dehydrate and crash fast. The margin between the first sign and a serious problem is measured in hours rather than days, and most general practices do not see these species — find a vet who does before you need one.

Go now

Do not wait for morning. Drive, or call ahead and drive.

Guinea pig: any difficulty breathing

Respiratory disease is a leading cause of death in guinea pigs, particularly young ones. Merck's instruction is to seek care immediately, because advanced cases progress quickly.

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Guinea pig: not eating, or straining to urinate, or blood in the urine

Guinea pigs are hindgut fermenters like rabbits and stop in the same way — Merck notes some decline rapidly and die suddenly. Blood in the urine or straining points at bladder stones, and a stone that lodges in the urethra is the same blocked-plumbing emergency as in a male cat.

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Hamster: watery diarrhea and a wet, matted back end

Wet tail. Dehydration is what kills, and a hamster is small enough that it happens fast. The guidance is to be seen by an exotics vet within 24 hours. Highest risk is 3 to 10 weeks old.

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Rat: visible effort to breathe, a click or wheeze, or mouth breathing

Mycoplasma is near-universal in pet rats and progresses. Early sneezing and watery eyes is a routine appointment. Once there is effort or gasping it is urgent.

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Any of them: hunched, cold, and not moving

In an animal this size that is late-stage, whatever the cause.

Be seen today

Call your vet for an appointment today, not next week.

Guinea pig drooling or dropping food

Overgrown teeth. Merck: see a vet quickly if a guinea pig drools or stops eating.

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Sneezing, watery eyes, or a red crust around the nose in a rat

Porphyrin, not blood. It means stress or early illness. This is the stage where respiratory disease is easiest to control.

Weight down two weeks running

Weigh weekly on kitchen scales. Weight drops before anything else shows.

Lumps

Common in rats especially, and much easier to remove while small.

Watch and write it down

Not an emergency. Note when it started and how often, and raise it at the next appointment.

A guinea pig that freezes and stops eating while you watch

They do this when nervous. Leave the room and check the bowl later.

Hamster asleep all day

They are nocturnal. Judge them in the evening.

What normal looks like

Guinea pig figures are Merck's own table. Hamster and rat figures come from a veterinary technician reference cross-checked against Merck, which broadly agrees but not exactly.

On the way

• Call aheadSo they can be ready when you arrive rather than starting from scratch. Say the species, the age, what you have seen and when it started.
• Take the packagingIf a substance is involved. Treatment for rat poison depends entirely on which of the five types it is, and you cannot tell from the color of the bait.
• Write down the timeWhen it started, how long a seizure lasted, when they last ate, when they last passed anything. You will not remember accurately once you are there.
• Keep the carrier dark and quietEspecially for birds, rabbits and cats. Stress alone makes a breathing problem worse, and in a bird in real distress the handling itself can kill.

What not to do

• Do not make them vomitNot unless a vet or a poison line has told you to. Salt can poison them, oil can go into the lungs, and for caustic substances it does more damage coming back up than it did going down.
• Do not give human painkillersOne regular acetaminophen tablet can kill an average cat. Ibuprofen ulcerates the stomach and damages the kidneys in both dogs and cats.
• Do not pull anythingNot string from a cat, not a stuck feather, not prolapsed tissue. Cut string if there is slack, keep tissue moist, and let a vet do the rest.
• Do not put your hands near the mouth during a seizureThey cannot control biting. Time it instead, and move furniture out of the way.
• Do not wait to see if it improves overnightThat sentence is on this page because it is the most common thing owners say afterwards.

Last reviewed October 2026. Written and maintained by Petdeals.io. General care information, not veterinary advice — for a sick animal, call a vet.