12/11/2025
Great article!
https://www.facebook.com/share/p/17KhRqFrQs/?mibextid=wwXIfr
IS YOUR DOG PUKING IN THE MORNING? (aka BILIOUS VOMITTING)...THIS IS FOR YOU...
Did you know morning pukes is very often the result of LOW stomach acidity, not high?!
You would think it was always an excessive thing, but here's what's often happening:
If a dog has low stomach acid (hypochlorhydria), their food isn’t fully digested after dinner. That's the first problem.
What follows now is that undigested food particles reach the intestines, where they will feed....something. As protein and fat are supposed to be fully digested at that stage for the good guys to eat, we're more talking bad guys here. This can lead to dysbiosis in their gut, which is highly inflammatory. So now you're sort of dealing with two things - low acid and a festering, crappy gut flora. Both often need addressing.
And it doesn't end there for low-acid doggos. As the stomach contents aren’t acidic enough, they don't trigger the pyloric sphincter (the gate valve to the small intestine) to stay closed tightly. It thinks digestion is complete. This means some of the bacterial-rich, acidic digesta from the intestines can sneak back up and into the stomach.
By early morning, that stagnant pool of bile-rich gloop has been sitting in their stomach, irritating the stomach lining. Your dog wakes up nauseous and vomits up the yellow foamy bile on the only bit of carpet you have left downstairs.
Unfortunately, the world believes that all reflux is simply "too much acid", take an antacid or a Rennie.
They will tell you not to use Rennie in dogs but ask them why! The only ingredient I can see in there that I wish wasn't is saccharin sodium, for me and them, but the toxic amounts of that are hundreds of tablets so giving him one or half is not going to harm him in the slightest.
There are lots of other antacids out there and no doubt some somewhere use sweeteners like Xylitol. This your dog cannot have.
Then there is the vet's favourite, Omeprazole.
Termed a proton-pump inhibitor, Omeprazole is a fancier way of doing the exact same thing the other two do for virtually nothing - neutralising excess acid in the gut, only while Rennie simply neutralises existing acid in the stomach (immediately relieving you of the acid burning), Omeprazole actually stops acid production. That means it takes longer to work but its effects last longer (many hours as opposed to 2 with the Rennie).
Herein lies the problem. If Omeprazole is used unwisely in a patient that is struggling to get their acidity up, not down, then the drug is very likely going to make things much worse for the patient over time.
Worse again, you'll see on the back of the packet that the top side effect of Omeprazole is gastrointestinal issues in the patient, such as bloat and gas. Know why? Because, by further lessening the amount of acid in the gut, you further hamper digestion, further fueling that dysbiosis, the top symptoms of which are excess gas from the ramped up bacterial numbers that are pigging out on the new food source (and ever worsening poo scores)
THE SIMPLE CHECK FOR HYPO ACIDITY BILLOUS VOMITTING...
Try adding a dash of Apple Cider Vinegar to your dog's dinner the night before. This will better acidify the stomach contents, triggering a stronger acid-secreting reflex in the gastric mucosa. He will more fully digest his dinner, and that sphincter might get the message, opening and closing properly.
For even better results, give the ACV before a meal. This is trickier but can be done with a small amount of food or a lovely drink of broth. They don't mind it. It's theorised that this "wakes" up the digestive process (The stomach’s acid secretion is tightly controlled by the vagus nerve and gastrin cells in the stomach. Sour or acidic tastes, especially on an empty stomach, trigger these pathways to reflexively secrete HCl and pepsin, ready for the meal).
So easy and well worth a shot. If it doesn't work you can try some of the stuff below.
OTHER SOLUTIONS FOR MORNING PUKERS...
Absolutely, you can and should try shifting the time of his meals around. If that works, great, but you shouldn't have to KEEP doing it, is the thing. Bandages like Rennie and Omeprazole are rarely the solution. They're a sticking plaster. Something is wrong. As ever, you need to find the "why" if you're ever going to recover. The top causes I can see are:
1. DYSBIOSIS
Maybe he doesn't have any low acid or something structurally wrong in there. Maybe he simple has a dysbiosis in the intestinal tract, causing lots of inflammation and its upsetting things. We know this is common enough too as such dogs are often remedied with a change in diet and probiotics. That shifts the biome, the good guys get back on top and presto, the problem resolves. If that doesn't work and you're pretty sure it's a SIBO (Small Intestine Bacterial Overgrowth, a blood test will often read low in vitamin B12 as an indicator...), FMT is wonderful too.
2. LOW PROTEIN FOODS
Gastric acid secretion is strongly stimulated by protein and mineral salts in food, especially animal protein and bone. Go figure! Ultra-processed or carbohydrate-heavy diets produce little stimulation, leading to chronic underuse of parietal cells. Over time, this reduces both acid output and pepsin activation. If you're still feeding high carb dry food, do your dog and cat a favour, read my book Feeding Dogs and jump over to real, biologically appropriate (lots of meat) diets for your meat eaters. Now's the time.
3. STRESS
Chronic stress (be it emotional or physical, thinking agility dogs) shifts the autonomic nervous system toward sympathetic dominance (“fight or flight”). This inhibits vagal (parasympathetic) signalling to the stomach — the main driver of acid secretion. Chronically anxious, kenneled, or pain-suffering dogs may therefore produce much less acid. What stressors is your dog under?
4. INFECTION
Helicobacter heilmannii among others, can get out of hand, usually after a dose of antibiotics, and begin to run rampant in the gastric mucosa, causing inflammation and loss of acid-secreting cells. Instead of focusing on how to kill Heliobacter (which you need in small numbers...) ask yourself WHY your dog got an infection there? What happened beforehand? Take a probiotic approach to fixing the infection before going for the na**lm.
5. OMEPRAZOLE
Chronic suppression of the acid-pumping parietal cell’s with Omeprazole leads to glandular atrophy and gastrin overproduction. This further dysregulates acid secretion, even when the drug is stopped. In fact, even short courses of Omeprazole can cause weeks of rebound hypochlorhydria (didn't they tell you?!).
6. HYPOTHYROIDISM
Thyroid hormone supports parietal cell function and gastric motility. Hypothyroidism reduces basal metabolism and acid output, contributing to chronic bloating, constipation, and poor protein digestion. A blood panel is needed to investigate this.
7. DAMAGE TO VAGUS NERVE
The vagus nerve emerges out from the thoracic spinal cord around T5–T9. If these vertebrae or surrounding structures are affected (chiropractors say particularly T6-T8), this can disrupt autonomic balance, reducing vagal stimulation and increasing “sympathetic tone”, which tends to suppress gastric acid secretion. If you think your dog might be a case, you need a chiropractor to check them over. Those, and acupuncturuists, are unbelievable at righting wrongs neither you nor your vet would ever know were there.
8. OVER-FEEDING
You've all heard about fasting by now. If not, read up. We're using our guts too much. They're active too much. And that's us omnivores, perpetual grazers. Dogs and cats eat sporadically. Perhaps its not MORE meals this animal needs but less. Check out the comments below - lots of folk jumped to one meaty meal a day and presto, problems evaporate.
9. AGE
In some studies, aged dogs have up to 50% lower basal gastric acid output compared to young adults. However, I assume this is simply the chronic effects of many of the above taking a toll over time *EDIT: folk are saying its a real thing below!). Not sure what you can do about the age thing. If you find something, let me know!!!
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If you're looking for something to help soothe his guts while you work on the cause, I recommend BioFunction8. It contains chamomile which is an anti-inflammatory of that area and marshmallow which adds some mucous to soothe things. Check out our Black November deals over on dogsfirst. ie/shop where you will find the majority of our supplements, including BioFunction8, all marked down by 33% for the month of November. While stocks last.
