Dear Dr. Barchas,

I have found my question asked by many dog
owners on the Internet, but it is never answered
by a professional veterinarian, so I’m hoping you
can address it in this site.

For months I have seen my one-year-old Miniature
Pinscher vomit a bright yellow foam-like, while at
the same time slimy substance. It happens
about twice every month and I have not been able
to find any pattern in it. It always occurs after
a mildly violent movement of her stomach as she
tries to get it out. This morning she did it again
together with diarrhea and the only thing I could
attribute it is just a couple of popcorn pieces
that she ate yesterday (maybe about three or
four). Otherwise she is only on pet food (Nutro
Natural Choice) and is a normal, active dog.

Please advise as to what may cause this type of
vomiting. She’s not a big eater, but she does eat
little pieces of food all day, so I don’t
understand why she would be vomiting bile in the
morning.

Thank you very much,
Maria – “Lana’s” mom.

Florida

First, the good news: I very strongly doubt that Lana has a serious medical problem that is causing her to vomit in the morning. There are some major diseases that can cause young dogs to vomit bile occasionally, but they are very rare. Since you do not mention other symptoms such as chronic lethargy or failure to grow properly, I’ll bet that Lana’s overall health is fine.

If Lana is like most of the dogs and cats I see for this problem, it will be very hard to determine precisely what is causing her to vomit. In fact, I have (at the request of my clients) done very thorough diagnostic evaluations on many pets with symptoms exactly like you describe. And usually we don’t get an answer.

So, what might be going on here, and what can you do about it?

You mention that Lana only vomits in the morning. Based on your description of what she brings up, it sounds like she is vomiting bile. That means she’s vomiting when her stomach is empty.

There is a chance that the problem is caused by excess acid that accumulates in Lana’s stomach overnight. The acid can irritate the stomach, leading to vomiting. Diarrhea might occur occasionally too if the irritation spreads throughout her system.

As well, Lana might suffer from a very mild form of inflammatory bowel disease, or IBD. Dogs and cats with IBD develop chronic irritation in their intestines, which may cause them vomit or have diarrhea at unpredictable intervals.

In either case, there are some simple steps you can consider. You can try giving Lana a snack or treat just before bedtime. If she has a little bit of food in her stomach during the night, less acid may develop.

Also, you may want to consider gradually switching her diet. Nutro is a fine food, and I do not think that it is at fault for this problem. However, there is a chance that the diet you are currently using simply does not agree with Lana. Therefore, changing foods (perhaps to a highly digestible “sensitive stomach” formula) may have an impact on the problem.

There are stomach calming medicines that might help with this problem, too. However, I would be very reluctant to medicate her without trying out the above recommendations first.

Finally, I should mention that there is a good chance that Lana will outgrow this problem in a year or two. Many dogs do.