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

Heartburn hits hard and fast-burning chest, sour taste, that feeling like your stomach is trying to climb up your throat. If you’ve reached for a pill without a prescription, you’re not alone. About 60 million Americans deal with heartburn at least once a month. And most of them turn to one of three types of over-the-counter meds: antacids, H2 blockers, or PPIs. But they’re not the same. Choosing the wrong one can mean wasted money, wasted time, or worse-worsening symptoms.

Antacids: Fast but Short-Lived Relief

Antacids are the OG of heartburn relief. Think Tums, Rolaids, or Milk of Magnesia. They work by neutralizing stomach acid right where it’s burning-like pouring baking soda on a fire. The result? Relief in under two minutes. If you just ate spicy food and feel it coming on, an antacid is your best bet.

But here’s the catch: it doesn’t last. Most antacids wear off in 30 to 60 minutes. That’s why you’ll see people popping five Tums after dinner, then another three after dessert. It’s not laziness-it’s biology. Calcium carbonate, the main ingredient in Tums, gives you quick neutralization but doesn’t stop your stomach from making more acid. In fact, 30% of users get rebound acid hypersecretion-meaning their stomach overcompensates and makes even more acid after the antacid wears off.

Antacids are perfect for occasional heartburn-less than once a week. They’re cheap ($2.99-$5.99 per pack), easy to use (just chew or swallow), and safe for short-term use. But if you’re using them more than twice a week, you’re treating the symptom, not the cause. And if you’re on other meds, antacids can mess with absorption. Take them two hours before or after antibiotics, iron pills, or thyroid meds.

H2 Blockers: Slower, But Lasts Longer

H2 blockers-like Pepcid AC and Tagamet HB-work differently. Instead of neutralizing acid, they tell your stomach to make less of it. They block histamine, a chemical that signals acid production. Think of it like turning down the volume on your stomach’s acid factory.

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 great for predictable heartburn: before a big meal, after wine with dinner, or if you know you’ll be lying down soon. Many people take famotidine (10 mg) 30 minutes before eating and avoid the whole episode.

They’re about 60-70% effective at reducing acid, which is good but not as strong as PPIs. And here’s another gotcha: they lose effectiveness after 2-3 weeks of daily use. That’s called tachyphylaxis. Your body gets used to them. So if you’ve been taking Pepcid every day for a month and it’s not working like it used to, that’s why.

They’re also more likely to interact with other drugs. Cimetidine (Tagamet) can interfere with blood thinners like warfarin and seizure meds like phenytoin. If you’re on any prescription meds, check with a pharmacist before starting H2 blockers.

PPIs: The Heavy Hitters-But Not for Everyone

Proton pump inhibitors-Prilosec OTC, Nexium 24HR, Prevacid 24HR-are the most powerful OTC heartburn meds. They shut down the acid pumps in your stomach cells. That’s not just reducing acid-it’s turning off the faucet. They suppress acid by 90-98%, which is why they’re the go-to for frequent heartburn (two or more days a week).

But they don’t work fast. You won’t feel relief the first day. It takes 24 to 72 hours to reach full effect. And you have to take them right-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. A lot of people give up on PPIs after day one because they expect instant results. That’s the biggest mistake.

And there are risks. The FDA warns that using PPIs longer than 14 days without a doctor’s advice can increase your risk of:

• Low magnesium levels (can cause muscle cramps, irregular heartbeat)
• Vitamin B12 deficiency (fatigue, numbness, memory issues)
• Increased risk of C. diff infection (severe diarrhea)
• Higher chance of hip fractures (especially if you’re over 50)
• Acute kidney injury (1.2 cases per 1,000 users per year)

Despite this, PPIs dominate the market-48% of OTC heartburn sales in 2022. Why? Because they work. A 2022 JAMA study showed PPIs reduced symptoms by 90% over 14 days. H2 blockers? Only 65%. For people with heartburn three or more times a week, PPIs are the only OTC option that delivers real relief.

Which One Should You Choose?

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

If you get heartburn:

• Less than once a week → Antacids (Tums, Rolaids)
• 1-2 times a week, predictable → H2 blockers (Pepcid AC, Tagamet HB)
• Two or more days a week → PPIs (Prilosec OTC, Nexium 24HR)

And here’s a rule most people miss: never take PPIs for more than 14 days in a row. The FDA requires this warning on every bottle. If your heartburn comes back after 14 days, don’t just restart the bottle. See a doctor. You might have GERD, a hiatal hernia, or something else that needs real treatment.

Some people combine meds. About 68% of frequent heartburn sufferers use an antacid on top of a PPI for breakthrough symptoms. That’s fine-if you’re following the rules. Take the PPI first thing in the morning, 30 minutes before food. Then if you get a flare-up at lunch, grab a Tums. But don’t double up on H2 blockers and PPIs. That’s overkill and increases side effect risk.

What Not to Do

Here are the top mistakes people make:

• Using PPIs for quick relief → They don’t work fast. You’ll be disappointed.
• Taking PPIs with orange juice → The acid destroys the enteric coating. Use water only.
• Staying on H2 blockers for months → They stop working. Switch to PPIs or see a doctor.
• Ignoring symptoms that won’t go away → If you’ve had heartburn for over two weeks, or you’re swallowing hard, losing weight, or vomiting blood-get checked. It’s not just acid.
• Assuming “natural” means safe → Baking soda and apple cider vinegar? They’re not regulated. Some make heartburn worse.

When to Call a Doctor

OTC meds are great for occasional discomfort. But they’re not a substitute for diagnosis. See a doctor if:

• Your symptoms last more than two weeks
• You have trouble swallowing
• You’re losing weight without trying
• You’re vomiting blood or your stool looks black and tarry
• You’re using PPIs more than three times a year

These aren’t signs of “bad digestion.” They could mean Barrett’s esophagus, ulcers, or even esophageal cancer. Early detection saves lives.

Bottom Line

Heartburn meds aren’t one-size-fits-all. Antacids give you fast, temporary relief. H2 blockers help if you know when it’s coming. PPIs are powerful, but only for frequent, ongoing issues-and only for 14 days at a time.

Know your symptoms. Match the med to the pattern. And don’t ignore warning signs. The goal isn’t just to silence the burn-it’s to protect your stomach, your esophagus, and your long-term health.