The fastest way to relieve heartburn is to take a liquid antacid containing calcium carbonate or magnesium, which can raise stomach pH in under a minute. But you likely want more than just one option, especially if you don’t have antacids on hand. Several approaches work on different timelines, from seconds to about an hour, and combining the right ones can get you comfortable quickly.
Antacids: The Fastest Option
Chewable or liquid antacids containing calcium carbonate or magnesium hydroxide neutralize stomach acid almost immediately. In laboratory models simulating stomach conditions, a calcium/magnesium carbonate antacid raised the pH of the gastric environment to a comfortable level within 40 seconds. In practice, it takes slightly longer because the product needs to reach your stomach and mix with its contents, but relief typically begins within a few minutes.
Liquid formulations work faster than chewable tablets because they don’t need to be broken down first. If you have both options in your medicine cabinet, reach for the liquid. Common brands include Maalox, Mylanta, and Tums (tablets). These are fine for occasional use, but calcium carbonate has a quirk worth knowing: it can trigger your stomach to produce more acid after the initial neutralizing effect wears off. This “rebound” effect happens because calcium stimulates the release of a hormone called gastrin, which signals your stomach to ramp up acid production. For a single episode, this rarely matters. If you’re taking antacids daily, it can create a cycle where heartburn keeps returning.
Alginate-Based Products
Products like Gaviscon work differently from standard antacids. Instead of just neutralizing acid, they form a floating gel barrier on top of your stomach contents. When the liquid alginate hits stomach acid, it reacts with bicarbonate and calcium to create a buoyant “raft” that physically blocks acid from splashing up into your esophagus. The onset is rapid, and the barrier can last for hours. This makes alginate products particularly useful for heartburn that hits after a large meal or when you need to lie down soon.
H2 Blockers: Slower but Longer Lasting
Over-the-counter H2 blockers like famotidine (Pepcid) take about an hour to kick in, so they won’t rescue you from heartburn that’s already raging. Where they shine is duration: a single dose provides relief for 4 to 10 hours. If your heartburn tends to return after antacids wear off, taking an H2 blocker alongside an antacid covers both the short and long game. The antacid handles the immediate burn while the H2 blocker reduces acid production over the following hours.
Proton pump inhibitors like omeprazole (Prilosec) are not fast-relief options. They take one to four days of regular use to reach full effect and are designed for frequent, recurring heartburn rather than a single episode.
What to Do Without Medication
If you don’t have anything in the medicine cabinet, a few physical strategies can help right now.
Stay upright or elevate your upper body. Gravity is your simplest tool. Lying flat lets acid pool at the opening of your esophagus. Sitting up, standing, or propping yourself on pillows so your chest is above your stomach gives acid less opportunity to travel upward. If you’re in bed, avoid stacking pillows under just your head, which can actually compress your stomach. Instead, elevate from the waist up, or place blocks under the head of your bed frame.
Lie on your left side. If you need to stay lying down, rolling onto your left side positions your stomach below the junction where it meets your esophagus. This makes it harder for acid to flow the wrong direction. Researchers at Amsterdam UMC confirmed that left-side sleeping reduces acid reflux episodes compared to right-side sleeping, where the stomach sits above that junction and acid escapes more easily.
Chew sugar-free gum. This one sounds odd, but chewing gum for 30 minutes after a meal stimulates saliva production, and saliva is naturally slightly alkaline. The increased swallowing also helps push any acid that has crept into the esophagus back down into the stomach. Studies show gum chewing consistently raises pH levels in the esophagus and throat. Bicarbonate-containing gum works even better than regular sugar-free varieties.
Loosen tight clothing. A snug belt or waistband puts direct pressure on your abdomen, which can push stomach contents upward. Unbuttoning your pants or switching to loose clothing removes that mechanical pressure.
Baking Soda as a Last Resort
Dissolving half a teaspoon of baking soda (sodium bicarbonate) in a glass of cold water creates a basic solution that neutralizes stomach acid on contact. It works, and it works fast. But the taste is unpleasant, and the sodium load is significant. The Mayo Clinic recommends no more than 5 teaspoons per day for the effervescent form and advises against using it for longer than two weeks. Baking soda is best treated as a one-time fix when you have nothing else available, not a go-to strategy. People on sodium-restricted diets or with kidney problems should avoid it entirely.
What Makes Heartburn Worse in the Moment
While you’re waiting for relief, avoid doing the things that fuel acid reflux. Eating more food, especially fatty or acidic foods, stimulates additional acid production. Bending over or doing abdominal exercises physically squeezes stomach contents upward. Drinking carbonated beverages increases pressure inside the stomach. Coffee and alcohol both relax the muscular valve between your esophagus and stomach, making it easier for acid to escape. Even water in large amounts can worsen symptoms if your stomach is already full, so sip small amounts if you’re thirsty.
Heartburn During Pregnancy
Heartburn is extremely common during pregnancy due to hormonal changes that relax the valve at the top of the stomach, combined with physical pressure from the growing uterus. According to Johns Hopkins Medicine, both antacids and H2 blockers are generally considered safe during pregnancy, with one caveat: most guidelines recommend avoiding these medications during the first trimester when possible. Positional strategies like left-side sleeping and staying upright after meals are the safest first steps during pregnancy. Eating smaller, more frequent meals also helps reduce the volume of stomach contents available to reflux.
When It Might Not Be Heartburn
Heartburn and heart attack can feel remarkably similar. Even experienced physicians sometimes can’t distinguish the two based on symptoms alone. The Mayo Clinic notes several patterns worth paying attention to. Heartburn typically produces a burning sensation in the chest and upper abdomen, usually after eating or when lying down. A heart attack more often feels like pressure, tightness, or squeezing in the chest or arms that may spread to the neck, jaw, or back, and it can be accompanied by shortness of breath, cold sweats, or lightheadedness.
If your chest pain is new, unusually severe, came on during physical exertion, or is accompanied by pain in your arm, jaw, or back, treat it as a potential cardiac event and call emergency services. Antacids won’t help a heart attack, and waiting to see if the pain goes away can cost critical time.