OTC Heartburn Medications: Antacids, H2 Blockers, and PPIs Explained

Heartburn hits hard-burning chest, sour taste, sleep ruined. You reach for the medicine cabinet, but with so many options-Tums, Pepcid, Prilosec-it’s easy to feel lost. Which one actually works? And why does your friend say PPIs are a miracle, but your doctor warned you not to take them long-term? Let’s cut through the noise. This isn’t about fancy labels or marketing claims. It’s about three real kinds of OTC heartburn meds, how they work, when to use them, and what you’re really signing up for.

Antacids: Fast but Short-Lived Relief

If you’ve ever chewed a Tums after a big meal, you’ve used an antacid. These are the OG heartburn fixers. They don’t stop acid production-they just neutralize it, like pouring baking soda into a fizzy drink. The reaction happens fast: within 30 to 120 seconds. That’s why they’re the go-to for sudden, occasional heartburn.

Common ingredients? Calcium carbonate (Tums), magnesium hydroxide (Milk of Magnesia), and aluminum hydroxide (Alternagel). A single Tums tablet can neutralize 12 to 24 milliequivalents of stomach acid. Sounds powerful? It is-until it’s not. The relief lasts about 30 to 60 minutes. That’s why people end up popping five tablets in an hour. It’s not addiction-it’s physics. The acid comes back faster than the pill can work.

Antacids are perfect for heartburn that happens less than once a week. Need relief after spicy food? Grab one. But if you’re getting heartburn every night? Antacids won’t cut it. And here’s a hidden catch: calcium-based antacids can trigger rebound acid hypersecretion. In about 30% of users, the stomach responds to neutralization by cranking out even more acid within a couple of hours. That’s why some people feel worse after the initial relief fades.

Also, don’t take antacids with other meds. They can bind to antibiotics, thyroid pills, or iron supplements and stop them from working. Wait at least two hours between doses.

H2 Blockers: Slower, But Lasts Longer

Think of H2 blockers as turning down the volume on your stomach’s acid factory. They don’t shut it off-they just tell the acid-producing cells to slow down. The key ingredient? Histamine. Your stomach cells use histamine to signal acid production. H2 blockers like famotidine (Pepcid AC) and cimetidine (Tagamet HB) block those signals.

They take longer to kick in-60 to 180 minutes-but once they do, they last 8 to 12 hours. That’s why they’re the smart pick for predictable heartburn. Planning a late-night pizza? Take a Pepcid AC an hour before. Going out for drinks? Dose up before dinner. They’re also the best OTC option for nighttime heartburn, since they cover you through the night.

Studies show H2 blockers reduce acid by about 60-70%. That’s less than PPIs, but more than antacids. And unlike PPIs, they don’t need days to build up. One dose can make a difference.

But there’s a catch: tolerance. After 2-3 weeks of daily use, your body starts to adapt. The acid suppression drops. A 2021 study in Alimentary Pharmacology & Therapeutics showed H2 blockers lose about half their effectiveness after continuous use. That’s why they’re not meant for long-term, daily treatment. They’re a bridge-not a solution.

Also, cimetidine can interfere with blood thinners like warfarin and seizure meds like phenytoin. If you’re on any prescription drugs, check with a pharmacist before using H2 blockers regularly.

PPIs: The Heavy Hitters-Use With Care

PPIs-proton pump inhibitors-are the strongest OTC heartburn meds you can buy without a prescription. Drugs like omeprazole (Prilosec OTC), esomeprazole (Nexium 24HR), and lansoprazole (Prevacid 24HR) shut down the final step of acid production. They target the proton pumps in stomach cells-the actual machines that spit out acid. Block those, and acid production drops by 90-98%.

But here’s the kicker: they don’t work right away. It takes 24 to 72 hours to reach full effect. That’s why people think PPIs aren’t working after one day. They’re not supposed to. You need to take them daily for 3-5 days before you feel the full benefit. And they only work if taken correctly: 30-60 minutes before breakfast. Why? Because that’s when your stomach’s pumps are most active. Take them after eating, and you’re wasting your money.

They’re the only OTC option recommended for frequent heartburn-two or more days a week. A 2022 JAMA Internal Medicine study found PPIs reduced symptoms by 90% over 14 days, compared to 65% for H2 blockers. If you’re dealing with chronic heartburn, acid reflux, or even Barrett’s esophagus, PPIs are the gold standard.

But they come with real risks. The FDA has issued multiple safety warnings:

• Long-term use (more than a year) increases hip fracture risk by 35%.
• They raise the chance of Clostridium difficile infection-a nasty gut bug that causes severe diarrhea.
• Chronic use can lead to low magnesium, low vitamin B12, and even kidney damage. Johns Hopkins research in 2023 linked daily PPI use over a year to a 23% higher risk of chronic kidney disease.
• They can cause acute interstitial nephritis (a kidney inflammation) in about 1.2 out of every 1,000 users.

And here’s the kicker: you’re only supposed to use them for 14 days at a time. Then you wait 4 months before starting another 14-day course. Yet a 2023 JAMA commentary found that 43% of users take them longer than recommended. That’s not just misuse-it’s dangerous.

Also, don’t take PPIs with orange juice. The acid in the juice can break down the enteric coating that protects the pill until it reaches the small intestine. Crushed or dissolved, the drug gets destroyed before it works.

Which One Should You Choose?

It’s not about which is “best.” It’s about which fits your symptoms.

Use an antacid if:

• You get heartburn less than once a week.
• You need instant relief after a meal or drink.
• You’re not on other medications that could interact.

Use an H2 blocker if:

• You get heartburn 1-2 times a week, especially after meals or at night.
• You want longer relief than antacids offer.
• You’re not planning to use it daily for more than 2 weeks.

Use a PPI if:

• You have heartburn two or more days a week.
• You’ve tried antacids and H2 blockers and they didn’t help.
• You’re willing to take it daily for 14 days, exactly as directed.
• You understand the risks and won’t use it long-term without medical advice.

Many people combine them. A 2023 Curist survey found 68% of frequent heartburn sufferers use an antacid for quick relief and a PPI for long-term control. That’s smart-just don’t rely on the combo as a crutch. If you need both regularly, you need to see a doctor.

What No One Tells You

Most people don’t realize that OTC heartburn meds treat symptoms-not the cause. If you’re getting heartburn daily, it’s not just about what you eat. It could be a hiatal hernia, obesity, smoking, stress, or even a medication you’re taking. PPIs might make you feel better, but they don’t fix the leaky valve in your esophagus.

Also, the market is flooded with generics. Prilosec OTC costs $25. Nexium 24HR is $20. But Curist’s generic versions? $5. Same active ingredient. Same FDA approval. No brand magic. You’re paying for the label, not the drug.

And if you’re using these meds for more than 14 days, twice a year? You’re overdue for a doctor’s visit. The FDA and American Gastroenterological Association agree: if OTC meds aren’t working, or you’re using them too often, it’s time to get checked. Heartburn can be harmless. Or it can be a sign of something serious.

Bottom Line

Antacids? Great for quick fixes. H2 blockers? Good for planned flare-ups. PPIs? Powerful-but only if used correctly and sparingly.

Don’t treat heartburn like a daily vitamin. It’s a signal. Listen to your body. Use the right tool for the job. And if you’re still struggling after 14 days? That’s not a prescription refill-it’s a red flag.