Can Dogs Have Tums for an Upset Stomach?

If you’ve ever wondered whether it’s safe for your dog or cat to take something like Calcium Carbonate (commonly known by the brand name Tums®) when they have an upset stomach or low calcium levels, here’s a full overview of how this medication works in pets and what you need to know.

Calcium carbonate is an oral calcium salt used in veterinary medicine for several purposes. In pets, it may be prescribed for low calcium levels (hypocalcemia) or used as a phosphate binder in patients with kidney disease. It can also serve as an antacid for conditions like esophagitis and gastroduodenal ulcerations, though in veterinary practice it is less common as an antacid because stronger, more specialized options often exist.

When used for chronic conditions, calcium carbonate is typically chosen alongside careful monitoring of calcium and phosphorus levels. For acute hypocalcemia crises, injectable calcium (such as calcium gluconate) is more commonly used instead. Although you can purchase over-the-counter forms of calcium carbonate, it should not be administered to your pet without veterinary supervision.

Brand Names and Other Names

In human medicine, calcium carbonate is available under various generic preparations and brand names (including Tums). There are no veterinary-specific formulations of calcium carbonate tailored solely for pets.

Uses of Tums for Dogs and Cats

In addition to antacid use (for esophagitis or gastric/duodenal ulceration), calcium carbonate sees more frequent use as a calcium supplement in animals with chronic hypocalcemia. It is also used to treat hyperphosphatemia (elevated phosphorus levels) associated with chronic kidney failure in dogs and cats. Because pets with renal disease may retain phosphorus, a phosphate binder such as calcium carbonate can help mitigate that risk.

Precautions and Side Effects

While generally safe and effective when prescribed by a veterinarian, calcium carbonate does come with potential risks. It should not be used in animals known to have a hypersensitivity to it, nor in pets whose calcium levels are already elevated.

The safety of calcium carbonate during pregnancy or in lactating dogs and cats has not been conclusively studied. Still, many veterinarians consider it safe during lactation. One possible long-term side effect is calcification of soft tissues if calcium levels become chronically elevated.

What Pet Owners Should Watch For

When giving calcium carbonate at home, it helps to keep an eye on how your pet responds from one day to the next. Most pets tolerate this medication well, but subtle changes can be your early hint that dosage needs adjusting or another treatment may be better. For example, some animals may experience mild constipation or firmer stools when first starting calcium carbonate. Others may seem less interested in eating or may show signs of stomach upset, especially if they already have sensitive digestion.

More rarely, changes in behavior can signal shifts in blood calcium levels. A pet who suddenly seems unusually tired, weak, or disoriented may be experiencing a calcium imbalance that needs attention. Pets with kidney disease or heart conditions are especially sensitive, so regular communication with your veterinarian and scheduled lab work are key.

Also pay attention to how your pet takes the medication. Chewable tablets may seem easy, but some pets dislike the chalky texture and require the pill to be hidden in food or given as a crushed tablet mixed into a meal. Always follow your veterinarian’s instructions and never change the dose without checking first.

Drug Interactions

Calcium carbonate may interact with other medications your pet is taking. For example, simultaneous use of other calcium products (like calcium gluconate or calcitriol) can push calcium levels too high (hypercalcemia). Pets with cardiac arrhythmias on heart medications such as digoxin also require special caution.

Certain antibiotics (for instance, tetracycline, doxycycline, and fluoroquinolones such as enrofloxacin or ciprofloxacin) may not be recommended when a calcium product is in use. Additionally, interactions may occur with thyroid supplements and stomach-medications like misoprostol, famotidine (Pepcid), ranitidine (Zantac), and cimetidine (Tagamet). It’s essential to discuss all medications your pet takes with your veterinarian and determine whether calcium carbonate fits into the overall treatment plan.

How It’s Supplied

Calcium carbonate is available in many oral forms, usually human-formulation products (since veterinary versions are lacking). Common oral tablets come in 500 mg, 750 mg, and 1000 mg sizes, and there are also oral suspensions (for example, 1250 mg per 5 mL). Because the formulations are human-directed, veterinary dosing needs careful adjustment by your veterinarian.

Dosing Information for Dogs and Cats

Never give calcium carbonate to your pet without first consulting your veterinarian. If costs are a concern, pet insurance may help. The dose of calcium carbonate varies widely based on the condition being treated, the pet’s size and breed, and how the pet responds to the initial dose.

Treatment duration depends on the underlying condition, how the pet responds, and whether any side effects develop. Even if the animal’s symptoms improve, it is important to complete the prescription unless directed otherwise, to prevent relapse.

When used as an antacid in dogs, one of the more common doses is around 0.5 grams up to 5 grams given orally every four hours as needed. For small dogs this might be 500 mg; for medium dogs 750–1000 mg; and for large dogs about 2000 mg.

As a calcium supplement, more typical daily doses look like: for cats, 1250 mg to 2 g per day; for small-breed dogs about 1250 mg/day; for medium dogs 2–4 g/day; for large dogs 4–6 g/day; and for giant breed dogs about 6–10 g per day.

For treating hyperphosphatemia in pets with chronic kidney disease, a commonly recommended dose is 41 to 68 mg per pound per day (approximately 90–150 mg per kg/day), divided doses and given with food. The dose is adjusted based on blood levels of calcium and phosphorus.