My guinea pig eats her cardboard hidey house. Is it bad? How to stop?

I think that it is valid that you have concerns about your guinea pigs. There are always risks of intestinal obstruction when animals eat their bedding, and if this started when you switched the bedding, I would recommend switching it back. Also, make sure they have plenty of fiber around, including lots of hay. If you would like to add something into the cage for them to chew on, cardboard boxes with no labels or tape work great! I hope that gives you a place to start!

Remove the Tunnels so she cannot eat the plastic. Get her some hard chew toys, apple wood pieces or similar where she can chew to take care of her teeth. She may also benefit from a veterinary exam of her teeth.

It is best to give them things to chew on that are made for guinea pigs but if you are going to use boxes it is best for them to be plain with no writing/ink. Here are some good treats for them. ( https://www.petco.com/shop/en/petcostore/product/oxbow-timothy-club:--bungalow-medium ) ( https://www.petco.com/shop/en/petcostore/product/oxbow-timothy-club:--bungalow-medium )

Depending on the size of the piece, it could cause an intestinal obstruction. If it was a small piece than it will probably pass through with no problems. Monitor for any abnormal signs and have a vet take a look at her if you notice anything concerning, like lethargy, decreased appetite, or gastrointestinal signs.

An immediate check up is required as this ingestion can lead to severe gastrointestinal side effects. Surgery to remove the wire may be needed. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.

They can chew on cardboard as long as they don't ingested large quantities. Offer rabbit safe wooden chew toys as well. Their teeth are constantly growing, so they need to chew to keep them at an appropriate length.

Congratulations on your new pet! You need to consider that a guinea pig is a pref species so they are naturally timid and defensive. You can't train them that things are wrong in the same way as say a dog. With gentle and regular handling he should broke much more tame. Chewing is completely normal and i would provide plenty of natural chews and replace the water bowl with a ceramic one.