Vet Guide to Antacids in 2025 🐾

Hi! I’m Dr Duncan Houston, BVSc—founder of Ask A Vet. Today, we’re exploring antacids and acid-reducers used off-label in dogs and cats to relieve upset stomach, ulcers, reflux, and CKD-related symptoms. Learn types, dosing, safety, interactions, and how to best support your pet’s comfort and GI health.

📘 What Are “Antacids”?

Veterinarians often prescribe:

• Neutralizing antacids: aluminum hydroxide, magnesium hydroxide, calcium carbonate (e.g., Maalox®, Tums®) :contentReference[oaicite:3]{index=3}
• H2 blockers: famotidine (Pepcid®), ranitidine (less used now) :contentReference[oaicite:4]{index=4}
• Proton pump inhibitors (PPIs): omeprazole (Prilosec®), pantoprazole—reduce acid production long-term :contentReference[oaicite:5]{index=5}

These are not FDA-approved for pets but are frequently used extra-label under veterinary guidance :contentReference[oaicite:6]{index=6}.

✅ When Vets Recommend Antacids

• Gastritis, acid reflux, bilious vomiting
• Gastrointestinal or esophageal ulcers
• Chronic kidney disease (phosphate-binding effect) :contentReference[oaicite:7]{index=7}
• As protective agents during NSAID or steroid therapies

They’re short-term solutions unless stomach issues are chronic. Consider deeper investigation for frequent symptoms :contentReference[oaicite:8]{index=8}.

📐 Dosing Overview by Type

Neutralizing Antacids

Calcium carbonate doses vary with pet size:
• Dogs: ~0.5 g every 4 hrs (small: 500 mg; medium: 750–1 g; large: up to 2 g) :contentReference[oaicite:9]{index=9}
• Can block phosphate in CKD—doses 90–150 mg/kg/day div. with food :contentReference[oaicite:10]{index=10}

H2 Blockers (Famotidine)

0.25–0.5 mg/kg every 12–24 hrs—best given on an empty stomach before breakfast :contentReference[oaicite:11]{index=11}

PPIs (Omeprazole)

0.7–1 mg/kg once daily (some need BID); ideally 30 min before meals for better absorption :contentReference[oaicite:12]{index=12}

⚠️ Side Effects & Precautions

Most antacids are well tolerated but watch for:

• Calcium/aluminum: constipation; magnesium—diarrhea; electrolyte imbalance :contentReference[oaicite:13]{index=13}
• Long-term use: nutrient malabsorption, kidney impact, especially in CKD :contentReference[oaicite:14]{index=14}
• PPIs: rare diarrhea/vomiting; gut flora changes—rare pneumonia risk :contentReference[oaicite:15]{index=15}
• Tums® caution: may contain xylitol (toxic), cause hypercalcemia or not effective in pets :contentReference[oaicite:16]{index=16}

🔗 Drug Interactions

• Antacids can affect absorption of many medications—corticosteroids, antibiotics, seizure meds, heart drugs, antifungals :contentReference[oaicite:17]{index=17}
• Famotidine and PPIs may alter drug metabolism or absorption :contentReference[oaicite:18]{index=18}

Always inform your vet of all medications and supplements.

🩺 Monitoring & Follow-Up

• Observe appetite, stool quality, vomiting, bloating
• Electrolytes and kidney values for chronic use
• GI protectants only as needed; taper PPIs after ulcer healing

⏱️ Missed Dose & Overdose

• Missed? Administer when remembered unless near next dose—don’t double.
• Overdose: vomiting, diarrhea, electrolyte issues, possible heart arrhythmia—seek vet care :contentReference[oaicite:19]{index=19}

🏡 Real-World Treatment Scenarios

🐶 Dog with NSAID-induced ulcers

• Start omeprazole 1 mg/kg q24 h for 7 days before meals + bland diet
• Add sucralfate and reassess endoscopy if bleeding persists

🐱 Cat with CKD & high phosphate

• Aluminum hydroxide with meals to bind phosphate; monitor calcium/phosphate every 2–4 weeks

❓ FAQs

Can I safely give Tums® to my dog?

No—xylitol risk, dosing unreliability, and better vet-prescribed options exist :contentReference[oaicite:20]{index=20}.

Famotidine vs. omeprazole—which is better?

H2 blockers (famotidine) act fast; PPIs (omeprazole) are more effective long-term—choose based on condition and vet guidance :contentReference[oaicite:21]{index=21}.

Can antacids cure gastritis?

No—they relieve symptoms. Underlying causes like infection or dietary issues must also be addressed :contentReference[oaicite:22]{index=22}.

📌 Final Takeaways

• Antacids can safely manage gastric upset in pets—when chosen and dosed appropriately.
• Use human products only under vet direction—watch for unsafe ingredients like xylitol.
• Monitor symptoms and lab values, especially during prolonged use.
• Always explore root causes—diet, ulcers, toxins—rather than masking symptoms.

Want help choosing the right antacid or managing GI health? Download the Ask A Vet app for personalized guidance, medication plans, and 24/7 vet support. Your pet’s comfort is our mission! 🐾❤️