- A 'linear foreign body' — very dangerous
- Varies
- Affects: Intestines
Why this verdict for dogs
String, thread, floss and ribbon are “linear foreign bodies” — instead of passing, they can bunch up and saw through the intestines, a surgical emergency. Never pull on a string you can see.
Warning signs to watch for
- Vomiting
- Not eating
- Straining
- Painful belly
⚠ If your dog ate string, yarn & thread
Act immediately — don't wait for symptoms.
- Call your vet or a pet poison helpline right away.
- Note how much was eaten and when.
- Do not induce vomiting unless a professional tells you to.
String, thread, tinsel, dental floss and ribbon cause a specific and particularly dangerous kind of blockage that vets call a linear foreign body. It is most common in cats, it behaves differently from a swallowed toy, and there is one piece of first aid that everybody gets wrong.
How much is safe?
Any length can do it, and the mechanism is what makes it so serious. One end snags — often around the base of the tongue, or at the stomach outlet — while the rest travels on. The intestine keeps trying to move it along and instead bunches up along the string like fabric gathered on a thread. Pulled tight, the string then saws through the bowel wall from the inside. Thread with a needle still attached is worse again, and Christmas tinsel is a seasonal classic.
What happens if a dog eats too much?
Repeated vomiting, refusing food, lethargy, hiding, and a tense or painful belly are the usual signs, developing over hours to a couple of days. If the bowel is perforated, the animal becomes rapidly and severely ill. Sometimes an owner sees string at the mouth or the anus — which brings us to the critical point below.
⚠ What to do if your dog ate string, yarn & thread
Never pull on string you can see, whether it is at the mouth or under the tail. If the far end is anchored inside, pulling can tear the intestine. Cut it flush if it is a tripping hazard, then call your vet immediately (ASPCA 888-426-4435 · Pet Poison Helpline 855-764-7661). Look under your cat's tongue if it will let you — a loop around the tongue base is easy to miss and highly diagnostic. Most cases need imaging and many need surgery, and outcomes are much better before the bowel is damaged.
⚠️ Worried your pet got into this?
Frequently asked questions
I can see the string — why can't I just pull it out gently?
Because you cannot know what the other end is attached to. This is the single most important rule with linear foreign bodies: cut, don't pull, and go to the vet.
My cat swallowed thread days ago and seems fine — is it over?
Possibly, but linear foreign bodies can sit and cause damage progressively. If there is any vomiting or appetite loss, get it checked.
Is this a risk for dogs too?
Yes, especially with ribbon, floss and toy stuffing, though cats are over-represented because of how they play and groom.
More household items for dogs
By the CanMyPet Editorial Team · Reviewed against ASPCA Animal Poison Control, the American Kennel Club (AKC) and Pet Poison Helpline · Last updated July 31, 2026.
Sources
- ASPCA — People Foods to Avoid Feeding Your Pets
- American Kennel Club — Dog Nutrition
- Pet Poison Helpline — Poison List