Nausea is an important sign to be able to recognize in dogs. We want to diagnose nausea as soon as possible to help our friend feel better quickly, but also because nausea can be a sign of something serious. By recognizing early signs of nausea, we have the opportunity to get our friend the help he needs as soon as possible.
It's important to know that vomiting is actually the last sign of nausea. The goal is to recognize and treat the earliest signs of nausea so that vomiting can be prevented. Of course, there are some cases where we actually do want a dog to vomit (like if he ingests chocolate or certain other toxins). With the exception of toxin ingestion, vomiting is typically something that we're trying to prevent.
So what are some of the earliest signs of nausea?
The earliest signs of nausea include decreased appetite, walking to the food bowl (not eating) then walking away, drooling more than normal, lip-smacking, lethargy (obviously lethargy can occur due to a number of reasons), or not eating at all.
Have you ever noticed these signs in your dog? If you have an adult dog, you've likely seen one of these behaviors at least once. If these early signs of nausea are missed, nausea can progress and vomiting may occur. We want to avoid vomiting because it contributes to dehydration, the patient feels terrible, and once vomiting has started injectable anti-emetics (anti-nausea meds) and subcutaneous (or intravenous) fluids are often needed to help them feel better again.
What can signs of nausea mean for a dog?
Dogs can feel nauseous for MANY reasons. Main categories of causes include (1) medication, (2) food, (3) underlying disease/foreign body.
If you have a dog that develops nausea, it's important to try to figure out the cause so you can determine if intervention beyond anti-nausea medication is indicated. Your veterinarian can help with this.
If your dog starts a new medication (antibiotics, pain medication, chemotherapy) and begins to have a reduced appetite, that medication may be the culprit. Call your vet if this occurs. If they think that nausea is related to the medication, they may prescribe an anti-nausea medication and will likely recommend stopping the original medication that made them feel sick.
There are many diseases/conditions that can cause a dog to feel nauseous. Too many to list in this article! The most common conditions to cause nausea are gastroenteritis ("stomach upset" due to food, etc.), pancreatitis, underlying intestinal diseases such as inflammatory bowel disease (IBD) or cancer, stomach/intestinal ulcer, stomach cancer, bloat, etc.
Usually, if a dog develops gastroenteritis, this improves with supportive care (fluids, anti-nausea medication, anti-diarrhea medication, pain meds if needed). The other conditions are more serious and require more of a workup and intervention.
Nausea can be a sign of a serious condition. If your dog is feeling nauseous (but isn't vomiting), your vet may recommend (1) picking up an anti-nausea medication to help them feel better faster (2) bland diet such as boiled chicken and rice (3) subcutaneous fluids (fluids under the skin). If this isn't helpful or if nausea has been chronic, additional diagnostics (abdominal ultrasound, etc) are indicated to determine the cause of nausea.
If your dog begins to vomit frequently and suddenly, your vet may wonder if he may have swallowed something that has become stuck in the stomach or intestines; this is called a "foreign body". If it's determined (with x-rays or ultrasound) that the object is stuck and will not pass, it will need to be removed. Foreign bodies are removed with either endoscopy (passing a camera into the mouth and down the esophagus, and beyond, until the object is located, then retrieving the object with forceps) or surgery.
Now that you know all of the signs of nausea you should be able to detect nausea before vomiting occurs. Call your vet (or oncologist) if your dog feels nauseous so that they can help get him the help he needs.
Dr. Lori Cesario
Board Certified Veterinary Oncologist
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