Can Guinea Pigs Eat Onions? Good or Bad for Guinea pigs!

guinea pig with an onion

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Onions are full of antioxidants and vitamin C. This makes them a pretty healthy option for most people. They tend to be toxic to animals, however, and the guinea pig is no exception! In fact, for them, even a little bit of onion can prove fatal. 

This is due to the presence of a compound called disulfide. Disulfide can cause anemia in guinea pigs that is quite severe. The sugar content can also cause them digestive troubles, as it is quite high. Guinea pigs are meant to eat mostly fiber, with a sugar intake that is comparatively very low. 

Can Guinea Pigs Eat Onions


Can Guinea Pigs Eat Onions? You should avoid feeding your Guinea Pigs Onions at all costs. They offer no nutritional value and can harm your beloved Guinea Pig. A sign that your guinea pig has eaten an onion is a discharge from the eye and nose, and increased salivation. Onion-poisoning in guinea pigs is quite serious, seek the advice of a vet.

So, onions are one kind of fresh produce you will want to pass by when sharing with your Cavie. Fortunately, there are many, healthier food options for guinea pigs out there! 

About the Famous Onion

Onions are perhaps the most popular members of the family Allium. This family also includes leeks, garlic, chives, and more. The red, yellow or white vegetable is known for its strong flavor and aromatic nature. When it comes to culinary pursuits, many folks have come to rely on the onion. This has made it a staple in a variety of dishes worldwide. 

That we know of, onions have been consumed by humans for 7,000 years or more. The first traces date back as far as 5000 B.C. 

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Do onions make you cry? This is normal! Onions contain sulfuric acid, which creates a strong fume. Onions will not only cause humans to tear up but animals as well. In fact, eye discharge is one of the first signs that a guinea pig has accidentally eaten some. 

Onions are also a great source of vitamin C… for humans. For your guinea pig, you will want to find a much safer vitamin C alternative. 

What Are the Benefits of Onions for Guinea Pigs?

The only component beneficial to guinea pigs that onions have is vitamin C. You see, guinea pigs do not naturally create Vitamin C. This key nutrient is something that they must consume.

However, for guinea pigs, there are much healthier sources of vitamin C. Onions contain harmful disulfides, excess sugar, excess calcium, and more. 

Better Onion Alternatives

Not sure what else to feed your Cavie? Besides onions, there are plenty of other, better sources of vitamin C. For example: 

Tomatoes (the fruit but not the leaves) 


Green peppers 


Pellets (Some are vitamin C fortified) 

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The Risks of Onions to Guinea Pigs 

When a guinea pig gets into onions, perhaps the first thing you will notice is discharge from their eyes and nose. They may also exhibit increased salivation. Generally, guinea pigs do not vomit; this will instead be the first sign. 

From here, the health of the guinea pig will rapidly begin to deteriorate. Should you suspect your guinea pig has ingested onions, seek prompt veterinary care. 

Can guinea pigs eat onions?

Further complications in guinea pigs caused by onions include: 

Urinary problems. A serving of onion contains far more calcium than guinea pigs require. As a result, consuming onion will cause guinea pigs to experience urinary problems, kidney stones, and the like. 

Digestive trouble. Guinea pigs have digestive systems that are quite sensitive. In order for them to remain healthy, they must be kept at the proper balance. Sugar is something that they should not have much of. The sugar levels in onions are quite high. As their bodies are not built for it, guinea pigs will quickly take harm from this excessive sugar intake. 

Anemia. Of all of the effects of onions on guinea pigs, this is probably the most harmful. The disulfides in onions damage their red blood cells, causing respiratory troubles and ultimately anemia, both of which are quite severe. 

Death. Untreated, or left too long, onion poisoning in guinea pigs can prove fatal. Take your guinea pig in for proper veterinary care right away if you suspect they have eaten even a little bit of onion! 

What To Do If Your Guinea Pig Eats Onion

Do you think your guinea pig has ingested onion? Watch out for the first signs: discharge from the eye and nose, and increased salivation.

Even a small amount of onion can do your guinea pig serious harm. This is probably not a situation in which you will want to wait-and-see. That your guinea pig will go downhill is almost a certainty. 

From discharge and salivation, guinea pigs will then begin to experience tummy upset and overall digestive trouble. They may not be as keen on eating and pass too much or too little stool.

Finally, your guinea pig will become anemic. Untreated, all of this can ultimately become fatal! 

Onion-poisoning in guinea pigs is quite serious, and not something that you can treat yourself at home. You will want to call your vet immediately to give your guinea pig the best possible chance of survival. 

two guinea pigs
Look out for signs that your guinea pig has eaten an onion.
If they have, seek a vets advice!

How To Prevent Your Guinea Pig From Eating Onions

There are a few ways that naughty guinea pigs can get into onions. Indoors, they might find them in the pantry or kitchen. Outside, the garden is doubtlessly where the vegetable would be.

Before you let your guinea pig out to explore, make sure that the area in question is guinea pig-proof. As far as dangers to guinea pigs, onions and other poisonous food are some of the worst out there. These little guys like to munch. 

Wild guinea pigs tend to have a better sense about what to eat, and what not, to survive. Domesticated guinea pigs tend to be less aware of the risk, and may decide to try an unwise sample.

Before letting your guinea pig out, remove any potted plants from reach. Make sure that the pantry door is closed, and that there are no bags of onions on the floor or the like.

Never leave your guinea pig unattended inside or outside of the home. 

Should you wish to let your guinea pig outside, simply make sure the garden is blocked-off appropriately as well. 

Conclusion: Can Guinea Pigs Eat Onions?

So, as you can see, guinea pigs cannot eat onions… at least, not without taking real harm! Onions are perhaps one of the most poisonous vegetables for guinea pigs that there are.

The only benefit that onions really have for guinea pigs is that they contain vitamin C. However, this is simply not worth the risk. Guinea pigs develop urinary and digestive troubles upon the consumption of onion. Eventually, they also become anemic, a condition that is quite severe. Any of these things can prove fatal. 

Instead, feed your guinea pig other kinds of vitamin C-rich fresh produce known to be safe, like strawberries, blueberries, green peppers, and more.

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