“The most common guinea pig health problems are respiratory infections, vitamin C deficiency, dental overgrowth, bladder stones, skin mites and fungal infections, bumblefoot, and digestive slowdown. Warning signs include eating less, weight loss, fewer droppings, crusty eyes, wheezing, and hunching. A guinea pig that stops eating needs a vet the same day.”
Guinea pigs are hardy little animals when they’re well cared for, but they’re also experts at hiding illness. As prey animals, they instinctively mask weakness, so by the time symptoms are obvious, a problem may be serious. Knowing the common conditions and their early signs helps you act quickly. This guide covers the health problems guinea pig owners are most likely to face.
This guide is for general information only. Always consult a veterinarian experienced with guinea pigs if you’re concerned.
Signs of a Sick Guinea Pig
- Eating less or ignoring favorite vegetables
- Fewer, smaller, or misshapen droppings
- Weight loss (weigh weekly)
- Crusty or watery eyes, nasal discharge, or sneezing
- Wheezing or labored breathing
- Hunched posture and puffed-up fur
- Hair loss, scabs, or constant scratching
- Drooling or difficulty chewing
- Squeaking when urinating, or blood in urine
- Limping or swollen feet
For general rodent warning signs, see signs your rodent is sick.
1. Respiratory Infections
Respiratory infections are one of the most serious and common problems in guinea pigs. Bacteria such as Bordetella and Streptococcus are frequent causes. Symptoms include sneezing, discharge from the eyes or nose, crusty eyes, wheezing, and lethargy. Guinea pigs can decline quickly, so see a vet promptly.
Prevention: avoid drafts and dusty bedding, keep the enclosure clean, and don’t house guinea pigs with rabbits, which can carry Bordetella without showing symptoms.
2. Vitamin C Deficiency (Scurvy)
Guinea pigs can’t make vitamin C and need it daily from food. Deficiency causes swollen, painful joints, reluctance to move, a rough coat, poor appetite, bleeding gums, and slow healing. It also weakens the immune system, making other illnesses more likely.
Prevention: feed fresh vegetables rich in vitamin C, such as bell peppers, and a fresh, fortified guinea pig pellet. Ask your vet about supplements. See what guinea pigs can eat.
3. Dental Problems
Guinea pig teeth grow continuously. If they don’t wear down evenly, they can overgrow or become misaligned (malocclusion). The back teeth can form sharp points or even grow across the tongue, making eating painful.
Signs: drooling, dropping food, eating slowly, weight loss, and overgrown front teeth.
Prevention: unlimited grass hay is the best way to keep teeth healthy. Vets can trim or file overgrown teeth.
4. Bladder Stones and Sludge
Guinea pigs are prone to urinary stones and “sludge,” a buildup of calcium in the bladder. Signs include straining or squeaking while urinating, blood in the urine, hunching, and a gritty white residue in bedding.
Prevention: avoid too much high-calcium food (like alfalfa hay for adults and heavy daily spinach or parsley), encourage drinking, and provide plenty of exercise. Stones often need surgical removal.
5. Skin Problems
- Mites: certain mites cause intense itching, hair loss, and scabs. Severe cases can lead to seizures from the discomfort. Vets can prescribe safe treatments.
- Lice: visible as tiny moving specks in the fur.
- Ringworm: a fungal infection that causes circular bald, flaky patches, often around the face and ears. It can spread to people.
Never use flea or tick products made for dogs or cats; some are toxic to guinea pigs.
6. Bumblefoot (Pododermatitis)
Bumblefoot is inflammation and infection of the feet, causing swelling, redness, sores, and limping. It’s linked to wire floors, rough or dirty bedding, obesity, and poor nail care.
Prevention: use soft, clean bedding and solid floors, trim nails monthly, and keep guinea pigs at a healthy weight. See guinea pig cage setup.
7. Digestive Slowdown (GI Stasis)
If a guinea pig stops eating, its gut can slow down or stop, leading to gas, pain, and a dangerous cycle. Causes include stress, pain, dental disease, and sudden diet changes. A guinea pig that hasn’t eaten or passed droppings for several hours needs urgent care.
8. Heatstroke
Guinea pigs overheat easily above about 80°F. Signs include panting, drooling, weakness, and collapse. Move the guinea pig to a cool area and call a vet immediately. See summer heat safety for rodents.
9. Eye Problems
Hay pokes, infections, and a fatty growth called “fatty eye” (usually harmless) can affect guinea pig eyes. Cloudy, red, or discharging eyes should be checked by a vet.
10. Ovarian Cysts and Reproductive Issues
Older female guinea pigs commonly develop ovarian cysts, which can cause hair loss on the flanks, a swollen belly, and behavior changes. Females bred for the first time after their pelvic bones have fused, often around six to eight months of age, face a high risk of life-threatening birthing complications. That’s one reason breeding should be left to experienced keepers.
Quick Symptom Guide
| Symptom | Possible Causes | Urgency |
|---|---|---|
| Not eating | Dental pain, GI stasis, illness | Emergency |
| Wheezing, discharge | Respiratory infection | Same day |
| Squeaking while urinating | Bladder stones or infection | Same day |
| Hair loss, scratching | Mites, ringworm, cysts | Within a few days |
| Swollen feet | Bumblefoot | Within a few days |
| Swollen joints, rough coat | Vitamin C deficiency | Within a few days |
Preventive Care Routine
- Weigh weekly and record results.
- Check eyes, ears, teeth, feet, and skin during handling.
- Feed unlimited hay and daily fresh vegetables.
- Keep the enclosure clean and dry.
- Trim nails monthly.
- Schedule annual checkups with an exotic vet.
See how to find an exotic vet and our complete guinea pig care guide.
Guinea Pigs and Capybaras Share Some Risks
Capybaras, the guinea pig’s giant cousins, also depend on dietary vitamin C and have continuously growing teeth, so they face similar risks. See capybara health problems.
Choosing a Vet for Guinea Pigs
Not all vets are trained to treat guinea pigs, and some medications that are safe for dogs and cats can be dangerous for them. Certain antibiotics, for example, can upset a guinea pig’s gut bacteria and cause severe illness. Look for a vet who regularly sees guinea pigs, ask about their experience with dental procedures and bladder stones, and find out whether they offer emergency care. Save the number of an after-hours exotic clinic as a backup.
Frequently Asked Questions
How do I know if my guinea pig is sick?
Watch for changes in appetite, droppings, weight, breathing, and activity.
Why is my guinea pig sneezing?
Occasional sneezes can be dust. Frequent sneezing with discharge suggests a respiratory infection.
Why is my guinea pig losing hair?
Common causes include mites, ringworm, and ovarian cysts in females.
How long can a guinea pig go without eating?
Not long. A guinea pig that hasn’t eaten for several hours needs prompt veterinary attention.