How to treat gastrointestinal problems in guinea pigs

Diarrhea often occurs as a symptom of a secondary condition, including disease, infection or improper diet, all causing the guinea pig’s digestive system to become upset. Whatever the reason, diarrhea needs to be treated promptly, as it can lead to dehydration and even death in severe cases.


Guinea pigs suffering from diarrhea may display symptoms such as:

  • Lethargy
  • Dehydration
  • Loss of appetite
  • Abdominal pain
  • Loose, watery stool
  • Soiling of the fur near the genital and anal area
  • Dull and depressed appearance
  • Rough hair coat
  • Sunken eyeballs
  • Hunched posture
  • Abnormally low body temperature (in severe cases)


Bacterial, viral and parasitic infections can all lead to digestive problems in guinea pigs, and thus diarrhea. A diet consisting of more grains and soluble sugars and little or no fiber can also cause diarrhea in guinea pigs, as it can upset the bacterial population and increase the harmful bacteria inside the animal’s digestive system.


Other than observing your guinea pig’s clinical signs, your veterinarian will confirm a diagnosis of diarrhea by completing a dietary history of the animal and examining its blood and stool samples for infectious organisms.


It is important that your guinea pig drinks enough water. If your guinea pig is refusing to drink, your veterinarian may provide additional fluids intravenously. Antibiotics should only be used when absolutely necessary because their use can worsen the imbalance of bacteria in the digestive tract.

Living and Management

Dietary management is essential, regardless of the cause of diarrhea. Feeding your guinea pig plain yogurt with active cultures, or the commercial supplement probiotic, may help restore the healthy balance of “good” bacteria in its digestive tract. Otherwise, provide plenty of water for your guinea pig to drink.


Ensuring that adequate roughage is included in your pet’s diet can prevent diet-related diarrhea. Diarrhea due to an infection, on the other hand, may be prevented by keeping the guinea pig’s bedding, water bottle, and living environment clean and sanitized; promptly removing uneaten food before it rots can also reduce the level of disease-causing organisms.

How to treat gastrointestinal problems in guinea pigs

Guinea pigs make great pets. While they are usually healthy animals, there are a number of diseases that commonly affect pet guinea pigs. By knowing what the most common illnesses are, you can be better prepared to monitor for signs and symptoms that your guinea pig may be getting sick.

Signs and Symptoms of Common Guinea Pig Ailments

All guinea pigs are different and even the five most common health ailments can present differently in different animals. It is important to note any change in behavior, appetite, elimination (urination and defecation), or other daily habits. Be aware of physical changes such as hair loss, skin redness, or swelling. Monitor any changes and speak with your veterinarian if you suspect there might be something off with your pet guinea pig.

How to treat gastrointestinal problems in guinea pigs

Melissa Ling ©. The Spruce 2019


Guinea pigs should always be eating and defecating. If you see your guinea pig hasn’t touched its food and you are seeing fewer and smaller stools being passed, your guinea pig may have ileus. Ileus is caused when gas builds up in the gastrointestinal tract (stomach and intestines). Due to the lack of normal peristalsis and no food coming into the digestive system, gas is unable to leave the body. This causes discomfort and can actually be life-threatening. Your guinea pig should receive immediate medical attention if you suspect ileus, so it can get a diagnosis and be prescribed the proper medications.

Ileus can be caused secondarily by an underlying illness or stressor which, in turn, causes your guinea pig to stop eating. Monitor food intake and be aware of how any changes may have impacted your pet.


If your guinea pig has hair loss and is itching or scratching a lot, it may have lice or mites. The thought of having these things in your house—much less on the guinea pig—may make you itch all over. Lice or mites can be easy to avoid and treat. Lice and Demodex mange mites are conditions that can both cause itching and hair loss. Lice and their eggs are usually seen in the bald patches behind your guinea pig’s ears and the mites can be seen microscopically all over the body. Speak with your veterinarian if you suspect any of these parasites to determine the best course of action.

Guinea pigs can give these parasites to each other and can also get them from toys and bedding. Be aware before introducing any new guinea pigs if they seem to have any skin conditions. Before introducing food or bedding into the cage, make a habit of freezing it for a day. The extreme cold temperatures will kill off any potential parasites that may have been lurking in the packages.

Uterine and Ovarian Diseases

Spaying your female guinea pig is definitely recommended. If she is living with a male, this will ensure population control and prevent multiple litters of guinea pigs. Besides preventing babies, females often develop uterine and ovarian issues, including various cancers, and having your female spayed can prevent these issues. Sometimes the uterus and ovaries can be removed even after the problem has been discovered but other times cancer has already spread to other parts of the body, rendering it untreatable. A complete ovariohysterectomy can be performed by your exotics vet on your guinea pig to prevent uterine and ovarian diseases, just as it would in a dog or cat. While some guinea pig owners are not able to justify the cost of the procedure, others see the great benefit to having their guinea pigs longer and not having to pay for emergency treatment when they notice their pig is sick.

Respiratory Diseases

Guinea pigs are sensitive to cold air drafts and can easily develop an upper respiratory infection or even pneumonia if you have a baby guinea pig. They can even get Bordetella bronchiseptica from your dog, cat, or pet rabbit. Take notice of your guinea pig's cage location and be sure to keep them away from drafts, open doors, and open windows. This simple act will help decrease the likelihood of them getting a respiratory infection. Wash your hands after handling other animals, including guinea pigs at pet stores, your dog or cat if they are coughing or sneezing, and even your rabbit. If you or your family are feeling ill, it's best to keep your germs to yourself.


More commonly referred to as bladder stones, uroliths often form in the bladder of pet guinea pigs. They cause pain and discomfort in your pet and you may also notice that their urine is often bloody due to the irritation the stone causes. If you notice infrequent urination or bloody urine, call your veterinarian right away and they will do some tests to determine the cause. Bladder stones are often found on radiographs being taken for a diagnosis of ileus and must be surgically removed.

Disease Prevention

Guinea pig ailments can be hard to diagnose. The best way to keep your guinea pig healthy is to keep a close watch on your pet. Make sure it is eating and defecating, wash your hands before and after handling, freeze your pet’s bedding and food before use, and keep it away from drafts. These actions will help you prevent the bulk of the most commonly seen diseases, though there are, of course, numerous other diseases that affect guinea pigs. To rule out anything else or to look for internal issues, an annual physical examination with your exotics vet is always recommended.

Guinea pigs are well developed at birth and within a few months are able to eat an adult diet. They are strict herbivores, that eat only plants, and like rabbits, are hind-gut fermentors that practice coprophagy (ingestion of one’s own faeces).

How to treat gastrointestinal problems in guinea pigsDigestive System

Coprophagy may be a source of B vitamins and a means of optimizing protein utilization. However, its precise contribution to the nutritional needs of guinea pigs is not fully known. As hind gut fermentors, guinea pigs digest much of their food in the caecum and colon (large intestine), which are at the end of the digestive tract. The caecum, a large, thin-walled sac located at the junction of the small and large intestine, contains up to 65% of gastrointestinal (GI) contents. Within the caecum, bacteria and protozoa aid digestion of foods taken in by the guinea pig.


Fibre is needed for these bacteria and protozoa within the caecum to stay in balance and function properly. Fibre also aids in maintaining normal GI motility or movement. Without fibre, the gastrointestinal tract slows down, resulting in subsequent changes in the caecum pH, fermentation and bacterial population. With time these changes in the intestinal tract environment can lead to indigestion.

You can provide this essential fibre by feeding your guinea pig free-choice grass hay. Oxbow recommends feeding unlimited quantities of timothy, orchard or oat hay.

Hay also helps prevent boredom by satisfying your guinea pig’s innate desire to chew, which is an important means of dental health maintenance.

In addition to hay, Oxbow’s Adult Guinea Pig Food is a high-fibre pelleted diet which contains stabilized vitamin C and is designed to meet the specific nutritional needs of your guinea pig.

Health Concerns

Guinea pigs are becoming a more valued, loved and cared for pet in the eyes of their owners, and as a result, veterinary care for guinea pigs has increased. Veterinarians seeing guinea pigs are noticing several health problems attributed to nutrition: vitamin C deficiency, gastrointestinal ileus, obesity, enteritis and urolithiasis.

Vitamin C Deficiency

Signs of vitamin C deficiency (scurvy) include:

  • Hind leg weakness
  • Gum inflammation
  • Unkempt fur coat
  • Bleeding in the joints or under the skin.

Like humans, guinea pigs are unable to produce their own vitamin C and require a dietary source. Daily requirements of vitamin C range from 20-50 mg per kg of body weight. In order to prevent vitamin C deficiency and subsequent scurvy, Oxbow recommends feeding your guinea pig Adult Guinea Pig Food, a pelleted diet containing stabilized vitamin C.

Gastrointestinal Ileus

Gastrointestinal ileus (malfunction of the digestive tract due to gut slowdown) is commonly seen in guinea pigs on low-fibre diets. Many times pet owners do not notice the signs associated with gastrointestinal slowdown until it is too late. Decreased appetite, a bloated or tense abdomen, along with lethargy and a decrease in the volume and size of faeces passed are all signs of gastrointestinal ileus.

Diets that incorporate high levels of nondigestible fibre in the form of free-choice grass hay promote increased gut motility and thereby prevent this gut slowdown. Oxbow’s Adult Guinea Pig Food is made from high-quality timothy hay that provides the appropriate fibre needed for healthy digestive system function.


Obesity in guinea pigs can lead to respiratory, heart and liver disease. Typical guinea pig feeds on the market contain high levels of fat, commonly over 3% and as high as 5%. These feeds contain corn, oats, and other grains that are designed to appeal to the consumer, but raise the starch and energy content of the food. When these high-fat foods are fed freechoice, obesity can occur.

Obesity not only leads to the previously mentioned health problems, but can also prevent coprophagy, which is necessary for the maintenance of normal gastrointestinal health. Oxbow’s Adult Guinea Pig Food was designed to prevent obesity by adding sufficient fibre, while at the same time eliminating grains that raise fat content. This combination of high fibre and low fat aids in overall digestion.

The minimum fibre level of Oxbow’s Adult Guinea Pig Food is 25% and the maximum is 28%, thus providing a healthy balance of fibre and energy.


Enteritis (intestinal inflammation associated with toxin production) is a problem commonly associated with diets that contain high levels of energy (starch and glucose). A low-fibre, high-starch diet promotes gut hypomotility and changes the intestinal pH and microbial population which allows pathogens (bad bacteria) to produce toxins that can be fatal.

The guinea pig with enteritis may have soft stools and be hunched and inactive due to increased GI gas production and the resulting abdominal pain. High fibre, low-starch Adult Guinea Pig Food is formulated to prevent enteritis.


Urolithiasis (bladder stones) is being seen in more and more guinea pigs. Although many are secondary to urinary tract infections, a certain percentage of stones are caused by an imbalance of calcium and phosphorus in the diet.

Grass hay is a forage feed, the natural diet for a wild guinea pig, has a higher calcium to phosphorus ratio. Grains have the inverse relationship and contain more phosphorus than calcium. Research has proven that diets containing an inverse ratio of calcium and phosphorus can cause stones and soft tissue calcifications. Dietary levels of vitamin D and magnesium may also influence the development of bladder stones.

Oxbow’s Adult Guinea Pig Food provides the mature guinea pig with the proper calcium to phosphorus ratio and appropriate levels of vitamin D and magnesium.

Oxbow Essentials – Adult Guinea Pig Food

Oxbow Animal Health agrees with nutritionists and veterinarians that less nutrient dense diets are needed to prolong the lives of small mammals, especially guinea pigs and rabbits.

Adult Guinea Pig Food is specifically designed to meet the maintenance nutritional needs of the adult guinea pig. The first ingredient in Adult Guinea Pig Food is timothy hay, which veterinarians recommend for improving the nutritional health of guinea pigs. Timothy hay mirrors the proper calcium to phosphorus ratio found in natural forages, stimulates gastrointestinal motility, and aids in the prevention of obesity.

Through the science of nutrition, Oxbow Animal Health wants to provide adult guinea pigs with the opportunity to live longer and healthier lives.

How to treat gastrointestinal problems in guinea pigsDr. Peter Fisher is owner and director of the Pet Care Veterinary Hospital in Virgina Beach, Virginia.
He specialises in the critical care of small mammal exotics.

The guinea pig digestive system is pretty amazing – it’s not easy to survive on a diet of mostly grass! But this complicated system is also very delicate, and it’s important that your piggie gets the right diet in order to stay happy and well. Read on to find out more about the guinea pig digestive system and learn how to keep your pet in the best of digestive health.

What do guinea pigs eat in the wild?
In the wild, guinea pigs live in the Andes Mountains in South America. They mainly eat grass, although this will generally be tougher and dryer than the grass we’re used to seeing in our gardens! They’ll also forage other wild plants as and when they find them.
A diet based mainly on grass isn’t exactly full of energy, and it would be pretty indigestible for us humans. However, guinea pigs have developed a highly specialised digestive system so they can live on this high-fibre vegetation.

How to treat gastrointestinal problems in guinea pigs

How does the guinea pig digestive system work?
The first clever thing about the guinea pig digestive system is the teeth. Since guinea pigs need to munch on tough vegetation all day, their teeth would get worn shorter and shorter if they were like ours! But instead, guinea pigs have ‘open rooted’ teeth that continually grow to compensate for all that wear.

After the teeth, the most impressive part of the guinea pig digestive system is the large intestine. This is the part that’s super specialised to extract energy and nutrients from a diet of tough vegetation.

At the start of the large intestine, guinea pigs have a huge sac called the caecum and this is full of loads and loads of microbes. These ‘friendly bacteria’ are the secret to success for our guinea pig friends, as they can break down tough fibre and release lots of nutrients for the piggie to take in!

There is a catch though: some of these nutrients can’t be absorbed in the caecum. In particular, certain vitamins and other goodies can only be absorbed earlier in the digestive tract. But guinea pigs can’t make the contents of their large intestine flow backwards towards their stomach! So they’ve developed a cunning way of dealing with this problem that seems quite disgusting to us humans.

Put simply, they eat their own poo. But not all of it – just certain special pellets that are called ‘caecotrophs’. These caecotrophs contain valuable nutrients from the caecum, such as amino acids and vitamins B and K. By eating these poop pellets, the guinea pig can absorb all the goodness they missed out on the first time round.

How to treat gastrointestinal problems in guinea pigs

What’s really special about guinea pig dietary needs?
While everything we’ve described about the guinea pig digestive system so far is pretty impressive, guinea pigs share these traits with rabbits and other herbivores who also need a high-fibre diet. But is there anything really special about the dietary needs of our piggies? The answer’s actually yes – they do have an unusual quirk that none of our other pets share.

This quirk is that they have a special requirement for vitamin C. While other animals can make their own vitamin C in their bodies, guinea pigs aren’t able to do this. Interestingly enough, out of all the animals we commonly talk about, it’s just guinea pigs and primates like us humans that must be careful to eat enough vitamin C in our diets.

Vitamin C is really important in the body – it’s needed for healthy gums, joints and skin, and it’s also important for the immune system to work properly and for wounds to heal well. Without enough of this vitamin in their diet, guinea pigs can become very poorly with scurvy. You can learn more about guinea pigs and vitamin C in our guide.

How to treat gastrointestinal problems in guinea pigs

How to support a healthy guinea pig digestive system
The secret to supporting healthy guinea pig digestion is to feed a diet based on what they’d eat in the wild. Since the natural diet for guinea pigs is mostly grass, our pet piggies should have a diet that’s 80% hay or grass. All this fibre will help keep their herbivore teeth and guts nice and healthy.

When it comes to hay, there are loads of different options to choose from and the wide array of options can be bewildering! In general, the tastiest and healthiest choices for guinea pigs are Meadow hay, such as Russel Rabbit Tasty Hay, or Timothy hay, such as Science Selective Timothy Hay. To learn more about the importance of hay in a guinea pig’s diet, check out our blog.

Alongside their hay, piggies will need a portion of fresh veg and some high-quality food that’s been formulated specifically for guinea pigs. It’s important that the food contains enough vitamin C, and ideally this should be stabilised so it will remain at high levels throughout the shelf life of the product. Both our muesli-style mix Gerty Guinea Pig Tasty Mix and our single-component diets Gerty Guinea Pig Tasty Nuggets and Science Selective Guinea Pig contain stabilised vitamin C to meet your furry friend’s nutritional needs.

How to treat gastrointestinal problems in guinea pigs

How to identify guinea pig digestive system problems
Choosing the right diet is a big step towards keeping your piggie’s digestive system healthy, but it’s also important to know the signs that might indicate there’s a problem that needs treating. If you see that your pet has loose poo or diarrhoea, it’s best to take them to the vet to get them checked out.

A lack of appetite is another sign that should set the alarm bells ringing. The incredibly complicated guinea pig digestive system relies on a constant input of food, and so these creatures can run into no end of problems if it grinds to a halt. It’s a big issue for our piggies to go off their food, and it’s best to get veterinary help as soon as possible to stop them getting very ill.

A third sign to look out for is if your guinea pig stops eating their caecotrophs. Obese piggies or those with arthritis may struggle to get around to reach these pellets, and this can upset their delicate digestion. It can also increase the risk of flystrike, as their back end can get quite messy. If you think that your guinea pig may not be eating their caecotrophs, take them along to your vet to find out what care they need and whether there’s an underlying cause.

We hope you’ve found this a useful guide to the guinea pig digestive system! The important thing to remember is that a good diet is the key to keeping your piggie’s digestion ticking along well. If you give your little friend lots of hay, some good quality food containing enough vitamin C and a portion of fresh veg every day, they’ll be well set up to keep happy and healthy.