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How to Tell If Your Dog Has Worms

Paul has been an online writer for over four years. His articles often focus on pet ownership.

How you can tell if you dog has worms, and what to do about it.

How you can tell if you dog has worms, and what to do about it.

Worms are one of the most common health problems for a dog. Fortunately, most cases are also very treatable. Since your dog can't speak English, you need to be vigilant and watch for any unusual behavior.

Unfortunately some types of worms do not cause noticeable symptoms until they dog's health is at risk. That said, the most common types are fairly obvious.

Signs of worms include fatigue, scratching the rear, and visible worms in the feces.

Signs of worms include fatigue, scratching the rear, and visible worms in the feces.

Signs That Your Dog May Have Worms

  • Visible worms or eggs in the feces. This is the most common sign of infection. However, not all kinds are visible to the naked eye.
  • Visible worms in fur or around dog's rear. Tapeworms in particular may appear as small moving segments which later dry out to resemble grains of rice.
  • Scratching or rubbing of rear. If you dog scratches their bottom on the ground or against furniture, they may be itchy due to infection. Itchiness however can also have other causes.
  • Visible worms in vomit.
  • Bloated stomach or belly. This is often seen in puppies who get worms from their mother.
  • Weakness, increased appetite, constant hunger, and weight loss. Worms steal their host's nutrition.
  • Diarrhea, particularly with blood.

How Worms Spread

  • Through mother. Newborn puppies can become infected by their mothers. Roundworm eggs form dormant cysts in adult dogs. These eggs themselves are not treatable, but are activated when the host dog becomes pregnant. A mother dog's milk can also pass roundworms to puppies.
  • Dirt. Roundworm eggs and hookworm larvae can live in dirt. If you dog comes into contact with infected dirt, they can become infected.
  • Fleas. Young tapeworms can reside in fleas, infecting a dog that swallows fleas while grooming.
  • Hunting. Wild animals may carry worms. If your dog hunts or eats wildlife, it may become infected.
There are several different types of worms that afflict dogs, from roundworms and whipworms to the sometimes fatal heart worm.

There are several different types of worms that afflict dogs, from roundworms and whipworms to the sometimes fatal heart worm.

  • Roundworms can grow up to six inches in length. They live in the intestines and appear as small, noodle-like bits in fecal matter. They cause swollen bellies and are an especially big problem for puppies.
  • Hookworms are thin and small. They bite or "hook" into the intestinal wall and are not always visible to the naked eye. Hookworms can cause internal bleeding, resulting in bloody stool or anemia.
  • Tapeworms are flat, long worms that live in the intestines. Segments of the tapeworm break off and are visible to the naked eye as rice-like grains after they dry out.
  • Heartworms are among the most dangerous because they are so hard to detect. They are spread by mosquito bites. Normally, until the larvae mature and congregate inside the dog's heart, they produce no symptoms or signs of illness. Heart damage can be fatal. Signs of heartworm infection are weakness, coughing during exercise, severe weight loss, fainting, coughing up blood and, finally, congestive heart failure.
  • Whipworms are thin and thread-like. They live in the large intestine. Adults may be visible to the naked eye, but do not tend to appear in feces so can be difficult to detect. A microscope examination of several fecal samples may be necessary. Whipworms are one of the most difficult worms to eliminate, but they are treatable.

How to Treat Your Dog

If you think your dog has worms, take your pet to the veterinarian. There are safe and effective treatments available, which your vet will likely prescribe. For the most common types of worms, there are some all-in-one medications in flavored chewable tablets.

  • Iverhart Max tablets are used to treat common worm conditions. The tables include three active ingredients: ivermectin, to prevent heartworm, pyrantel pamoate, to treat roundworms and hookworms, and praziquantel, to treat tapeworms.
  • Selamectin is also used to treat and prevent heartworms, hookworms, and roundworms.
  • Milbemycin oxime is used to prevent heartworms, hookworms, roundworms, and some whipworms.
  • Paziquantel is used to treat tapeworms.

Some vets even recommend that especially vulnerable dogs take monthly tablets to prevent worms.

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Has your dog ever had worms? Share your advice here.

Diane on May 05, 2020:

My chicua is 6 months old got him for my birthday he has been pooping blood drags his but don't know if he has worms inm with him right now he is barely breathing . Don't know what to do please any body please help

Mark John Swanson on February 28, 2019:

My dog is scratching your rear on the floor

gailsafford9@gmail.com on February 15, 2019:

I think my dog has worms I need to no a medicine I can give to help her . I believe it is heart worms she cough when playing also around her rectom she bites at and scoots her bootie .

Piper eddlemon on December 23, 2018:

My dog had worms he had roundworm and grd. Now I would advise any one that thinks that their dog has worms to take them to a vet. Because if you think that your dog has worms but you don't have the money to take him to a vet , you think I'll just buy it in the store . Wrong , you don't know what type of worms that your pet has and you might end up buying one that doesn't treat what worm your pet has. I don't have money either and vets are expensive so look online for a low cost clinic . You'll be glad you did. Never assume that the medicine you buy in the store will work then you go by more . Now you could have spent that money and taken him to a vet and been 100 percent sure there treatment was a success.

Bea on October 31, 2018:

I have 3 chihuahuas, ages 10, 9 and 3. My male 10 year old has been puking on and off for awhile now, low energy, and most troublesome, fussing with his rectum. He stops in mid stride to check out his butt and he constantly licks at it. Haven’t noticed any worms in his poop though, his poop has been smaller than normal though. My other dogs have no symptoms though. They haven’t been to any dog parks, mostly are in their own back yard. Maybe yeast infection? Idk

Kerry on September 22, 2018:

Any home remedies to treat dog mites and fleas

Donna Franzen on July 27, 2018:

No is treated for heartworms

kconlay on June 18, 2018:

My dog rocko has never had worms. But I have noticed that he's been licking at his bum and rubbing it against the floor. I've already been trying to come up with enough for his shots he's due for. Now I'm worried about him doing that and if he's going to be alright. He's like my baby attached to me basically by the hip. I love him so much and thing's have been so tight if at all. Any advice that could help me I would greatly appreciate. Please no hate, the world can be ugly enough without our help, and I don't think I could handle it. Thank you for your time or any helpful advice

Hokur13@hotmail.co.uk on March 31, 2018:

Our 7/8 week old terrier puppy has been treated for worms by the vet. It’s now been nearly 3 weeks & her tummy is still swollen. Is this normal?

kamsananthan on March 20, 2018:

thank you very much,your advice very esantail for all dogs keepers

90%of the people having dogs do not care or think about a such kind

of worms including me.

Aleesha on December 20, 2017:

Hi, I'm only 11 years old and I need help healing my dog by myself. I think my dog has worms. She is constantly licking her bottom. I need advice on treating my dog correctly and by myself. Again, I am only 11 so I can't afford a doctors appointment by myself. I really need our help - Aleesha

Judy on October 15, 2017:

My dog was rescued from a shelter where he was taken from a kennel he was always in and abused. I immediately got him check at my vet and he had a lump on his back at the time and hot spots near his tail. He has always itched around there and bitten. Lately he's been scratching under my bed against the frame constantly. Tonight I went to give him his haircut. I cut it really short once a month. Tonight I noticed that there was something moving as I got to his right side. A bunch of small white bugs it appeared. So I got the clippers at that point and shaved him all the way to the skin on his back and sides and ended up shaving his whole body. As I was shaving him I could see them coming out of his skin. They seemed to get worse when I shaved that spot. Also about a week or so ago I noticed a white bump form on his right side. He's had them before and I thought nothing of it. These looked like maggots. When I gave him a bath in dawn and oatmeal, I noticed his entire body was covered in red spots. I read to put aloe or something on it to sooth it but I feel like there are a lot more in him. Advice would be wonderful until his appointment which is Monday.

sam stanners on August 12, 2017:

earlier this morning my dogs stools had a tape worm in it i have given him the correct dose of tablet now all funny noises are comming out of his stomach is this normal

Gilbert Garcia on May 06, 2017:

My dog has diarrhea but has non of the symptoms that worms would give you but I say that in poop there were white round things in her poop and they didn't move or anything don't really know what they are if anyone does let me know be really helpful

Emily Wiggins on April 25, 2017:

My dog has had worms before. I think he has them again because he was scooting his rear on the floor but it might be something that is just itching him. When he had them I took him to the vet and got some tablets that helped really well.

dyamane0726@yahoo.com on April 16, 2017:

How would I no if I'm giving my dog the right worm medicine? I'm unable to afford to take my little pincher about 9 years old. I usually give him "worm out" tablets every 3-6 months. Can I buy these medicines in pet store ? Or he only can get treated by get?

Schmusse katze on June 07, 2013:

Very nicely done. Just one thing I think you need to change. Worms in dogs excrete an enzyme that decreases the dogs appetite.

whitebob_king on April 09, 2013:

i just keep on washing her hair.

imagelist lm on April 04, 2013:

Nice lens...

GeekGirl1 on March 22, 2013:

Thanks for this lens. Informative.

bossypants on March 22, 2013:

Just got back from the vet with a worm diagnosis. Yuck! We've administered the tablets she prescribed and now know what to look for. Although our dog was on a heartworm med, she somehow ended up with a tapeworm and round worms. Totally grossed out but glad we found them before the infestation got worse. Thank you fro your informative article!

anonymous on March 21, 2013:

@Cookie2112: I agree that a natural wormer is a better solution - chemical wormers are toxic. It's easy enough to get information online; I just found out that grapefruit seed extract and fresh garlic, freshly ground pumpkin seeds, or wheat germ oil are all good natural de-wormers. Unfortunately, they don't tell you the dosage or how to administer the remedy.

Cookie2112 on March 08, 2013:

@suepogson: i have just bought a puppy from a large home breeder and she seemed really knowledgeable on lots of things. She told me that butternut squash is a natural wormer for dogs - you must chop it all up and including the pips in the mixture give to the dog about 3 times a week (1 tablespoon) in with regular dog food. She said it works on all her dogs and they love it too, she told me that the worming treatments you buy from a pet shop / vets are basically pesticides!!!

AnimalHouse on March 07, 2013:

I will take note of the dewormer products that you have listed. This lens is very helpful! Thanks for sharing!

tamibradfitzgerald on March 02, 2013:

I dewormed my 8 week old puppy a week ago. There are still a few random worms in her leavings but I'm noticing small white pod like things. Can anyone tell me what these are?

nichole-sams on February 21, 2013:

We wormed our puppies 7-10 days ago and they have a pot belly. Why?

suepogson on February 16, 2013:

I live on a tropical farm with outdoor dogs - some worms seem unpreventable so it's treatment I'm looking for - natural if possible.

kaylee-johnson-31392 on February 15, 2013:

ok what i do know about worms is that they can be ingested through other animals pooping on grass and the dog eats the grass, you can buy de worming medication at walmart in the pet section where the grooming stuff is, and read the label, it will tell you if its safe to use on puppies. that's just common sense, no need to panick. :)

maymay0522 on February 14, 2013:

i have a pit puppy that just turned a month yesterday and i saw worms tonight, since he is too young to go outside can my other dogs get the worms? a 9 month old pit bull and a 10 year old yorkie poo

mrssnake08 on February 10, 2013:

i have a 9 week old pitbull puppy...he has worms I took him to petco to get his shots and a dewormer but it seems that his belly isn't getting any smaller how do you know if he has gotten rid of the worms

mary-podmore on February 03, 2013:

@ellen-gipe: I would definately get to the vet on monday, they will give you the meds to get rid of them, they may also treat your other dog to be safe. Sounds like her shots are fine but never got de-wormed.

ellen-gipe on February 03, 2013:

Good Heavens!! Brand new puppy born 11-11-12; WE adopted Sat. Feb 2,2013, 6 hours into adoption the puppy takes a poo and about 1 inch white worms dominate in poo. What on earth do I do??!! We bought her from an elderly lady and she gave us Shot information, and also the Registration to get the puppy registered as she is a pure bread. Very loving dog, but I also have another dog and now I am completely freaking out. ANYONE, PLEASE respond that has an answer that will be helpful.

mary-podmore on January 25, 2013:

@lalee1963: I think it's tapeworms, I was looking for the explanation myself because my dog is having the same issue. They are coming from her rear area and in her stool, and look like maggots until they dry. Hope this helps.

lalee1963 on January 10, 2013:

@bad-ass-cass23: I'm thrilled to hear that! Like I said, she has no other signs so I was hoping it was an external factor.

bad-ass-cass23 on January 10, 2013:

@lalee1963: I've seen these dried up worms on my floor before when I didn't even have a dog. I'm not sure what they were but I don't THINK they came from your dog....

goodgreen2 on January 10, 2013:

I have 2 puppies there brothers and sister... by reading this page I realize my puppies has the roundworms... but they are only 5 weeks old.. and I wanna know if I can start treating my puppies now? I don't have the $ to take them to the Vet... what can i do?

lalee1963 on January 08, 2013:

@auntkimmie: It's definitely not maggots. These are much longer but still very small. They are definitely worms of some kind. Thanks though!

auntkimmie on January 08, 2013:

@lalee1963: to me it sounds like maggots but im not sure what they come from

lalee1963 on January 05, 2013:

I recently moved to the south and have seen some of the strangest bugs since then. Lately I have been seeing these weird dried out worm things on the kitchen floor. They are thin and very short. Are they coming from my dog (who have no signs of worms, otherwise) or could be be something from outside?

Amy Trumpeter from Oxford on December 31, 2012:

I usually worm him every 3-6 months. Thanks for this great lens.

crstnblue on December 27, 2012:

Very informative lens! : )

Thanks for sharing!

Blessed!

Donallphin on December 20, 2012:

Great photos and a fine lens. Very informative.

HeavenSweetBliss on December 18, 2012:

What a great lense! ...very informative and helpful!

mistaben on December 16, 2012:

Excellent information and helpful lens, thank you for sharing =)

Amy Trumpeter from Oxford on December 12, 2012:

This is a great and informative lens, thanks!

AnimalHouse on December 11, 2012:

Proper care and monthly check ups are great ways to avoid worms.

xtianfriborg13 on December 04, 2012:

Thank God our dog is safe from worms. He did not show any of the symptoms. Lucky him!

new-jersey-veterinarian on October 22, 2012:

Well written posting

anonymous on October 20, 2012:

What a great and informative lens. :)

mko9819 on October 12, 2012:

@Corinna_pupylover: If your dogs are losing weight but still eating normally (or more is usually the case) then they either have tapeworm or hook worms and need to be treated right away. Feed stores usually have the cheapest worm medicine. It's not to expensive to take care of but well worth it. Except when you have to clean up the poop that has the dead tapeworm in it. Then it's just disgusting.

spids1 on October 06, 2012:

Great lens very well written.

blue autumn on September 11, 2012:

My dog never had any problems with worms but one of my cats was super bloated for a long time and seemed perfectly fine because she had been that way since we got her. On a trip the vet they recommended a dewormer and she got super thin! guess that answered that

lynberg on September 08, 2012:

@Corinna_pupylover: take him to the vet with a sample of his fresh fecal matter. You have a responsibility to take care of your dog's health. They also need to draw blood to find out if it's heartworms. The longer you wait, the worse it can get.

lynberg on September 08, 2012:

@becky-goldstein-7: take him to the vet with a sample of his fresh fecal matter. They also need to draw blood to find out if it's heartworms. You have a responsibility to take care of your dog. The longer you wait, the worse it can get.

Corinna_pupylover on September 07, 2012:

@becky-goldstein-7: I have the same problem my puppy is getting skinnier but she is still active and eats her food but she seems to be gettig skinnier?!?

Anybody with A solution Please help me I love her and shes a German sheapord and a lab mix and I really want to see her grow :(

Dianeyp LM on September 04, 2012:

My dog has managed to avoid worms so far, but my cat hasn't! great lens

becky-goldstein-7 on September 03, 2012:

My dog has lost weight but still active and eating his food with no problem? What can be the problem?

Aleayah on August 16, 2012:

Thanks for great info!

KanesCanines on August 07, 2012:

Great information! A must read for a person who has a dog or puppy or thinking on getting a dog. Great stuff!

handmadewithlovealways on July 18, 2012:

my dog had a litter of pups just over a month ago - they do not seem to have worms but she does? Which would be the best course of action for me?

selene-lindhout on July 15, 2012:

I have a litter of puppies, i treated them fro fleas yesterday with stronghold flea and worm and today i found a 5 inchworm in the bed... I am hoping this will be the first of many to die im worried about my puppies.

tonimerritt on July 14, 2012:

what are u giving your dogs as a de-wormer?

dean-smith-315428 on July 14, 2012:

I just got a 6 week old pup today and within the hour it threw up roundworms. This being my first dog I was upset but I went out to TSC and got a dewormer. Gave him just a half teaspoon. He just just passed an incredibly large amount of worms less than 12 hours later. Possibly the grossest thing I have ever seen.

tonimerritt on July 14, 2012:

@victoria-greer-980: 4 yr old pug vomited up what looks like a hookworm and has been on ivehart max forever

tonimerritt on July 14, 2012:

@victoria-greer-980: looking for that answer as well

PuppyPadLady on July 07, 2012:

Great info..thanks for sharing!

poorwendy lm on July 07, 2012:

Worms in dogs sound painful. Yuck!

mistahtee845 on July 06, 2012:

@kdanielle711: thats usually from eating things that are not food. Like eating string. They get part of the stuff stuck in the butt till you or the dog pull the string out.

Stephanie Tietjen from Albuquerque, New Mexico on July 02, 2012:

Great coverage of worms. Fortunately, my dog has never had them and is on prevention.

victoria-greer-980 on June 30, 2012:

My dog he is 2 months and he vomited up a long white worm.... is that round worm? it was round.

WriterDave on June 28, 2012:

My puppy had worms, no fun!

bunitasmith on June 25, 2012:

Thank you for the information. Great lens.

derekswifey20 on June 23, 2012:

@beach1234: Sounds like roundworms to me since that's what my puppy had around the same age, and that's exactly the way I found out he had them. The vet confirmed it was indeed Roundworms.

stephen-perry on May 13, 2012:

@purefoy09: Hey purefoy09.

Mate I just purchased a British x Americian Staffordshire poor little guy had belly worms . You can purchase worming tablets from a vet or from the dog/cat food isle at your local supermarket. I think I picked up a 3 pack of tablets for about $17.00 ( $5.66 a tablet) . I fed my pup a tablet on Sunday while his belly was HUGE !!!!! The next afternoon on the Monday after work I checked on my little guy his belly is normal size now and you can see his definition. Looks like he had worms and the tablets fromn the super markert did the trick. I believe you have to do this once a month ?? I could be wrong .

Hope this helps .

purefoy09 on May 06, 2012:

some people have found a white puppy and i don't know what kind it is. They have asked me to hold on to it in case we find or ever find the owner. the puppies belly is very bloated and very hungry all the time ...i think it got worms from its mother since it is only like 8 weeks old maybe. i just need to know how to treat this poor guy, p;ease if there is anyone there right now i need help!!!!!

alana-deweever on April 23, 2012:

Thanks for the info. Really helped. By the way..that puppy is so adorable in the last pic. What kind of dog is that?

chiquitasmom9665 on April 21, 2012:

thank you for the info

angelwings1968 on April 20, 2012:

My dog,chloe,has a large belly,shakes at night and rubs her butt on the floor. Could this be worms?

iluvmybullys on April 03, 2012:

@justin89: omg take him to the vet immediately that's the only way you will know for sure

aquarian_insight on April 01, 2012:

Some great information and advice here. Luckily we've never had to deal with worms. Thank you.

justin89 on March 30, 2012:

my dog buddy just threw up worms and we gave him dewormer. but now is acting really off. and i don't know if these are all the syptoms of worms. hes very incohearent so dizzy he can't stant and falls over. hes drewling so much and shakeing when hes not cold at all almost looks like tremors. is this just a really bad case of worms or should i be worried it could be anything else?

justin-fransoo on March 30, 2012:

@kdanielle711: You should go to your local pet store as your dog seems to have one kind of worms , but there is a pill or chewable tablet that you can buy that treat's many kinds of commun worms dog have . Hope that help's your dog will be fine after a week to 10 days after taking the tablets

rpmweb on March 28, 2012:

Thanks for the useful info!

Fish oil for dogs

darby-skittles-benjamin on March 16, 2012:

Y dog nikki recently lost a lot of weight and you can see her cheekbones. She is constantly hungry and this worries me because she is outside a lot and tends to eat rocks and dirt so I was wondering what this might be?

Petmedication on March 16, 2012:

Nice Informative Article!

Pet Medications Online

AlphaChic on March 11, 2012:

Luckily, I haven't had to deal with my dog having worms, but I did find your lens very informative.

kdanielle711 on February 26, 2012:

I just got a five year old rat terrier about two weeks ago. When we first got her, she had ticks and fleas, which we treated for. The people we adopted her from said that she has only had her puppy shots, and she had been an outside dog for the past few months (she was an inside dog before then) and now she lives in my apartment. Today, when I took her out for a walk, her first excrement had came out but there was a little bit hanging out of her rear by a very thin string like thing. She started walking oddly and then sat down and used her two front legs to drag herself forward. She was able to get it off, but I'm worried about her. Can someone please tell me if this is a sign of worms or not?

HausZweiHomes on January 31, 2012:

adopted a rescue dog that had worms. It was given a milky substance (I can't remember the name) to squirt in his mouth once for 3 days by the animal shelter where we adopted him. He still has diarrhea, so I'm taking him to the vet tomorrow. I didn't think to check his stool till now and it does have a bit of blood in it. Anyone had this occur?

HausZweiHomes on January 31, 2012:

I adopted a rescue dog that had worms. It was given a milky substance (I can't remember the name) to squirt in his mouth once for 3 days by the animal shelter where we adopted him. He still has diarrhea, so I'm taking him to the vet tomorrow. I didn't think to check his stool till now and it does have a bit of blood in it. Anyone had this occur?

Pangionedevelopers on January 29, 2012:

congrats, great info

Edutopia on January 15, 2012:

Proper care and medical prevention should always be factored in to the cost of owning a dog. If you care for you dog the cost of heartworm prevention is well worth it than having to spend the money to treat them after putting your dog through the suffering of them in the first place.

queenofduvetcover on January 11, 2012:

My dogs take Iverhart every month to prevent worms. This is a very helpful lens, thank you! =)

jeremykim2011 on January 10, 2012:

Thank you so much for sharing. Very useful and informative lens.

JackieSonia on January 07, 2012:

Your lens is very informative. There's a lot of good advice here. My dog is due for the vet this month and I will make sure I ask questions and maybe find out if she should be on heartworm med. Thanks for sharing

jadehorseshoe on December 23, 2011:

A VERY useful lens.

Shana rios Chavez on December 03, 2011:

great lens

irenemaria from Sweden on November 26, 2011:

Good advices - thanks a lot

anonymous on November 21, 2011:

That's exactly why I have regular check ups for my dog.

peterwrite on November 20, 2011:

Great tips on dog worms your pets health should high priority to every owner.

anonymous on October 25, 2011:

good to know, 'thumbs up' for your explanation.