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

Heartburn hits hard - a burning sensation in your chest, a sour taste in your mouth, maybe even trouble sleeping. If you’ve ever reached for a bottle of Tums, Pepcid, or Prilosec without a prescription, you’re not alone. Nearly 60 million Americans deal with heartburn at least once a month. But not all OTC heartburn meds work the same way. Choosing the wrong one can mean wasted money, wasted time, or worse - side effects you didn’t expect.

How Antacids Work (and When They’re Actually Useful)

Antacids are the OG heartburn fix. They’ve been around since the 1800s. Think of them like a chemical sponge for stomach acid. They don’t stop acid production - they neutralize it right where it is. That’s why they work so fast.

If you just ate spicy food and feel the burn starting, an antacid like Tums (calcium carbonate) can knock out the pain in under a minute. Milk of Magnesia (magnesium hydroxide) and Alternagel (aluminum hydroxide) work the same way. You chew or swallow, and within 30 to 120 seconds, relief kicks in.

But here’s the catch: it doesn’t last. Most antacids only work for 30 to 60 minutes. That’s why people who take them often end up with a handful of pills by dinner. One study found that 63% of users complain about needing to redose constantly. That’s not a flaw - it’s how they’re designed.

Antacids are perfect for occasional heartburn - less than once a week. They’re cheap, widely available, and safe for short-term use. But if you’re using them daily, you’re treating the symptom, not the cause. And some types can backfire. Calcium carbonate, for example, can trigger rebound acid hypersecretion in about 30% of users. That means your stomach makes even more acid after the antacid wears off, making heartburn worse later.

H2 Blockers: Slowing Down the Acid Factory

H2 blockers - like Pepcid AC (famotidine), Tagamet HB (cimetidine), and Axid AR (nizatidine) - work differently. Instead of mopping up acid, they tell your stomach to make less of it. They block histamine, a chemical that signals your stomach to pump out acid.

They take longer to work - usually 60 to 180 minutes - but their effects last much longer: 8 to 12 hours. That’s why they’re popular for predictable heartburn. If you know you’ll eat pizza on Friday night, take a Pepcid 60 to 90 minutes before. You’re less likely to feel the burn later.

Studies show H2 blockers reduce acid production by about 60-70%. That’s not as strong as PPIs, but it’s enough for people who get heartburn 1-2 times a week. The American Gastroenterological Association recommends them as a first choice for this group.

But there’s a downside. After 2-3 weeks of daily use, your body can start to build tolerance. The same dose stops working as well. That’s why many users on Reddit and Drugs.com report that H2 blockers “stop working after a couple weeks.”

They also interact with other meds. Cimetidine can interfere with blood thinners like warfarin and seizure meds like phenytoin. Always check with a pharmacist if you’re on other prescriptions.

PPIs: The Heavy Hitters - Powerful, But Not for Everyone

Proton pump inhibitors - Prilosec OTC (omeprazole), Nexium 24HR (esomeprazole), and Prevacid 24HR (lansoprazole) - are the strongest OTC heartburn meds you can buy without a prescription. They shut down the acid pumps in your stomach cells completely. That’s why they suppress acid by 90-98%.

But here’s the twist: they don’t work fast. You won’t feel relief after one pill. It takes 24 to 72 hours to reach full effect. That’s why so many people give up on them too soon. One user on Amazon wrote, “I took it for two days and nothing happened. I threw it out.” That’s a common mistake.

PPIs are meant for frequent heartburn - two or more days a week. If you’re having heartburn every day, or waking up at night with it, a PPI is the only OTC option that can truly help. A 2022 JAMA study found PPIs reduced symptoms by 90% over 14 days. H2 blockers? Only 65%.

But they come with serious warnings. The FDA requires a boxed warning on all OTC PPIs about increased risk of Clostridium difficile infection (a severe gut infection) and hip fractures with long-term use. Studies also link daily PPI use to lower magnesium and vitamin B12 levels, kidney disease, and even pneumonia.

And timing matters. You must take PPIs before food - ideally 30 to 60 minutes before breakfast. If you take them after eating, or with orange juice (which breaks down the coating), they won’t work. One user on r/gerd said, “I used to take mine at night. Didn’t help. Then I started taking it before breakfast - game changer.”

And you’re not supposed to take them longer than 14 days in a row. The FDA made that rule for a reason. If your heartburn comes back after 14 days, you need to see a doctor - not just take another pack.

Which One Should You Choose?

It’s not about what’s “best.” It’s about what fits your pattern.

• Occasional heartburn (less than once a week)? Start with an antacid. Chew a Tums. You’ll feel better fast. Just don’t make it a habit.
• Predictable heartburn (1-2 times a week)? Try an H2 blocker. Take Pepcid 60 minutes before your trigger meal. It’s reliable, affordable, and works for most people.
• Frequent heartburn (two or more days a week)? A PPI is your best bet. But only use it for 14 days straight. If symptoms return, see a doctor. Don’t just buy another bottle.

Many people combine them. About 68% of frequent heartburn sufferers use an antacid for instant relief and a PPI for long-term control. That’s smart - if you do it right. Don’t take antacids and PPIs at the same time. Wait at least two hours. Antacids can interfere with how PPIs are absorbed.

What No One Tells You About OTC Heartburn Meds

Here’s the truth: OTC heartburn meds are not a cure. They’re a bandage. If you’re relying on them for months or years, something deeper is going on. GERD isn’t just “too much acid.” It’s often a weak lower esophageal sphincter, hiatal hernia, or even a food sensitivity.

Also, cost isn’t always a clue to quality. Generic PPIs now make up 68% of sales. Curist’s generic omeprazole costs $4.99 - less than a coffee. The brand-name version? $24.99. Same active ingredient. Same results.

And don’t ignore lifestyle. Losing 10 pounds can cut heartburn in half. Avoiding late-night meals, caffeine, and alcohol helps more than any pill. But if you’re already doing all that and still burning - it’s time to talk to a doctor. No OTC pill should be your permanent solution.

What to Do Next

Start by tracking your symptoms. How often? When? What triggers it? Write it down for a week. Then match it to the right OTC option.

• Once a week or less? Antacid.
• 1-2 times a week, same time each day? H2 blocker.
• Two or more days a week? PPI - but only for 14 days. Then stop and reassess.

If you’ve tried all three and still have symptoms - or if you have trouble swallowing, unexplained weight loss, or vomiting blood - stop self-treating. See a doctor. You could have GERD, a hiatal hernia, or something more serious.

And if you’re already on a PPI for more than 14 days? Talk to your pharmacist. Ask if you’re using it correctly. Ask if you need a different approach. You don’t need a prescription to get advice - just a conversation.

Final Thought: Don’t Just Pop Pills - Understand Why

Heartburn isn’t just about what you eat. It’s about how your body handles it. OTC meds give you control - but only if you use them right. Know your symptoms. Know your options. Know your limits. And when in doubt, talk to someone who knows more than the bottle does.