Two Easy Ways to Start Earning Rewards!
Become a member today!
Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
Already a member? Sign in
Become a credit card member today!
Earn 2X Pals Rewards points at Petco
when you use Petco Pay!
APPLY NOW
Learn More About Petco Pay Benefits

My 8-month-old puppy is lethargic for days but still eating. Why?

Updated on September 23rd, 2025

Pet's info: Dog | Giant Schnauzer | Female | spayed | 65 lbs

My 8 month old dog who is usually very active has been lethargic for the past 2 days. She still eats and drink and walk but everything is done slower.

4 Answers

Most Helpful Answer

Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS

Veterinarian

Published on December 19th, 2016

From the sign you are describing it is quite difficult to determine the underlying problem. General signs of lethargy could be commonly due to high temperature which may be related to an infection. In puppies gastrointestinal and urinary tract infections are by far the most common type of infections.
If the signs do not resolve in the next 24hours or if Luna is showing any inappetence, more evident lethargy or any other signs (vomiting and diarrhoea for example) I would strongly advice a veterinary check up.

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Joy Fuhrman, DVM, MBA, CPA
Veterinarian
Published on May 8th, 2018
Lethargy and inappetence are very concerning signs especially in a young puppy as they can lead to dehydration very quickly.

I recommend you have Max examined by your veterinarian right away. These are very general and non-specific signs so it is difficult to make any suggestions as to what might be going on.
1Pet Parents found this answer helpful
Answered By Rodrigo Roca, DVM
Veterinarian
Published on September 17th, 2018
Hello, sorry to hear about Guido. These are very vague and non-specific signs and are commonly seen in multiple scenarios. Most often, pups may have changes in their environment such as excessive heat which may make them more groggy but other times, pups may have a dietary indiscretion that could make them be lethargic. Both of these are often self limiting and not requiring your veterinarian to see them unless they develop persistent vomiting, diarrhea, more severe lethargy, or inappetence.

More severe causes of this could include parasites, allergies, ingestion of foreign material, and infections with parasites. If these signs persist longer than 2-3 days, or if he develops vomiting, diarrhea, lethargy, or a decreased appetite then have him evaluated by a veterinarian. Hope this helps and best of luck.
1Pet Parents found this answer helpful
Answered By Jessica Keay, DVM
Veterinarian
Published on June 10th, 2019
If your puppy is alert mentally, and is getting up and walking around/playing occasionally then I wouldn't classify this as extreme lethargy, so I wouldn't classify your description as a puppy that needs immediate veterinary attention, but we do usually see puppies being more playful so I would make an appointment at a vet's office for an examination once they are open. If the puppy becomes nonresponsive/unable to walk/raise its head then this would be extreme lethargy requiring urgent care.
1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

Why is my puppy tired and not playing, but still eating and drinking?

For puppies that are still eating and drinking but lethargic and no signs of GI issues I would be suspicious of a couple of things: 1) puppy is just sleeping more now because he is still growing, Pitt Bull terriers and other large breed dogs can go through pretty fast growth spurts and this can definitely cause pups to sleep more. 2) If puppy is overly lethargic and running out of breathe easily or becoming intolerant to exercise or play I would be suspicious of a cardiovascular abnormality. I would recommend you schedule an appointment to have a vet do a heart auscultation (listen to the heart with microscope) to ensure your pets heart does not have any arrhythmia's or murmurs.

Updated on September 23rd, 2025

My 7-month-old puppy is suddenly slow and lethargic. What's wrong?

Hi, and thanks for your question. This is a quite generic but concerning presentation. Differentials are many, from any disease that can spread systemically (causing lethargy for example) like infection, and anything that can cause pain/discomfort. The approach must be logic, A check up is needed if signs last for more than 24hours. 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. If this answer was helpful please let us know, this will be used to improve our service!

Updated on September 23rd, 2025

Health & Wellness

My Husky is lethargic, panting, and won't eat. What's wrong?

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Luna. Poor girl. Lethargy and a loss of appetite are both signs of illness that can include dental disease, systemic illness, infection, or injury. Without seeing her in person, I can't narrow it down. I'd have her seen by a vet today. The vet can diagnose what is causing her symptoms and can treat her. Best of luck!

Updated on September 23rd, 2025

Why is my 11-week puppy lethargic, not eating, and peeing herself?

Thanks for visiting Petco Pet Education Center, formerly Petcoach! Based on your description this could be a number of things. She is a large breed growing puppy so they often go through spurts of sleepiness where they may not eat as much of their food. With that said, this should then be followed by a spurt of activeness and engorging in her food, within a 24 hr period. If she is lethargic and not eating well for more than a day, then she may have an infection and should be checked out by your vet asap. Pets also don't often pee on themselves, even at this age. This concerns me for a possible urinary tract infection, which causes her to have an inflamed bladder, which then causes her to not be able to pee in a designated area. At almost 3 months of age though, she may still be potty training. At any rate, it is best to get her seen with such vague symptoms, just to make sure she doesn't have an infection and to get her treated right away if there is one present. I hope that your fur baby Sansa feels better soon! Best wishes and take care.

Updated on September 23rd, 2025

Health & Wellness

My 10-month puppy is lethargic, in pain, and vet meds aren't working.

I recommend having tests done on Luna such as blood work, a urinalysis, and possibly x-rays. This can help them diagnose what is going on with her. I would take her back into a vet today, poor girl.

Updated on September 23rd, 2025

My puppy is lethargic, won't eat or drink, and his stomach is big. Is he sick?

Irati is exhibiting symptoms of illness. Lethargy and loss of appetite are non specific symptoms with many causes. To determine the cause, she should be examined by your veterinarian. She may need bloodwork and a fecal exam to reach a diagnosis. Supportive care may be indicated until she is eating and drinking on her own.

Updated on September 23rd, 2025

My high-energy dog is suddenly tired and not playing. Should I worry?

I'm very sorry Sadie isn't feeling well! I can understand they you might be worried, but it is a good sign that she is eating every meal and drinking water. Lethargy is a very general sign of illness, and it can be caused by many different things such as systemic illness, infection, injury, or inflammation. I would monitor her for now, and if she is still lethargic in 24-48 hours, I would take her into the vet for a health check.

Updated on September 23rd, 2025

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share