For the most common Ultra Strength Tums (1,000 mg calcium carbonate), you can take 2 to 3 tablets at a time, with a maximum of 7 tablets in 24 hours. The exact limits vary by product strength, so checking your specific bottle matters.
Dosage Limits by Tums Strength
Tums comes in several strengths, and each one contains a different amount of calcium carbonate per tablet. That difference changes how many you can safely take in a single dose and over the course of a day.
The Ultra Strength formula (1,000 mg per tablet) is the most widely sold. Its label directs adults and children 12 and older to chew 2 to 3 tablets as symptoms occur, with no more than 7 tablets in a 24-hour period. The Regular Strength version (500 mg per tablet) allows more tablets per day because each one delivers less calcium. Regardless of which strength you buy, the label also states that you should not use the maximum dosage for more than two weeks straight.
A simple way to think about it: the stronger the tablet, the fewer you’re allowed per day. Always check the back of your specific bottle, since formulations can change.
Why the Daily Cap Matters
Tums neutralizes stomach acid, but it’s also a significant source of calcium. Three Ultra Strength tablets deliver 3,000 mg of calcium carbonate in a single dose. The NIH sets the tolerable upper limit for total calcium intake (from food, drinks, and supplements combined) at 2,500 mg per day for adults 19 to 50 and 2,000 mg per day for adults 51 and older. If you’re taking the maximum 7 Ultra Strength tablets in a day, you’re getting 7,000 mg of calcium carbonate on top of whatever calcium is already in your diet.
That’s why the two-week rule exists on the label. Occasional use for a bad bout of heartburn is one thing. Daily maximum doses over weeks or months can push your calcium levels into a range that causes real problems.
Risks of Taking Too Many
Consistently exceeding the recommended dose can lead to a condition called milk-alkali syndrome, which is almost always caused by taking too many calcium supplements, most often calcium carbonate. In the early stages there are usually no symptoms at all, which makes it easy to miss.
As calcium builds up, symptoms can include constipation, nausea, fatigue, confusion, excessive urination, irregular heartbeat, and back or flank pain related to kidney stones. In severe cases it can lead to kidney failure. The condition is reversible when caught early, but it requires stopping the calcium source and sometimes medical treatment to bring levels back down. If you find yourself reaching for Tums every day for more than two weeks, the heartburn itself likely needs a different approach.
Dosing During Pregnancy
Heartburn is extremely common in pregnancy, and Tums is generally considered a go-to option. The guidance for pregnant women is more conservative: take a maximum of 2 tablets every 4 to 6 hours as needed. For Regular Strength (500 mg), the daily cap during pregnancy is 10 tablets in 24 hours. For Ultra Strength (1,000 mg), the label drops to no more than 5 tablets in 24 hours.
Most pregnancy recommendations refer to the Regular Strength formula. Excess calcium during pregnancy carries the same risk of milk-alkali syndrome, and pregnancy already places extra demands on the kidneys, so staying within the lower limits is important.
Dosing for Children
Tums makes a kids’ formula with its own dosing chart based on weight first, then age. Children under 24 pounds or under 2 years old should not take Tums without a doctor’s guidance. For kids 24 to 47 pounds (ages 2 to 5), the dose is 1 tablet as needed, up to 3 tablets in 24 hours. Children 48 to 95 pounds (ages 6 to 11) can take 2 tablets at a time, up to 6 tablets in 24 hours. The same two-week maximum applies. Antacids can also interact with certain prescription medications, so if your child takes any other medicine, check with a pharmacist first.
How to Space Your Doses
The label says to chew tablets completely as symptoms occur, rather than on a fixed schedule. In practice, spacing doses at least a couple of hours apart helps you avoid hitting the daily maximum too early in the day. If you take 3 Ultra Strength tablets at lunch and 3 more at dinner, you’re already at 6 of your 7-tablet daily limit.
Tums works quickly, usually within minutes, but the relief is temporary because it only neutralizes the acid already in your stomach. It doesn’t reduce acid production. If you’re burning through your daily allotment regularly, that’s a sign the underlying cause of your heartburn needs attention rather than more antacids.