How Baking Soda Poisoning or Toxicity Occurs

Most cases of baking soda poisoning come from ingesting too much of it. Accidentally adding too much to food is rarely the culprit — most people don't enjoy the taste in large amounts. More commonly, people run into trouble when using baking soda to self-treat heartburn or indigestion. Antacid misuse accounted for 60% of baking soda toxicity reports between 2000 and 2012. Teeth whitening and other self-treatment attempts made up most of the remaining cases.

Sodium bicarbonate has legitimate medical uses — doctors use it to treat metabolic acidosis, certain drug intoxications, and severe diarrhea and vomiting. It also appears in some IV fluids, including those used for rehydration therapy. In clinical settings, overdoses typically result from an underlying condition, human error, or a clerical mistake rather than misuse.

Baking soda toxicity doesn't always come from swallowing it. In one case, a caregiver applied large amounts of baking soda to treat a four-month-old's diaper rash, resulting in toxicity through the skin. There have also been cases of IV bags spilling and splashing sodium bicarbonate solutions onto patients. Topical exposure like this produces different symptoms than ingestion but can still be dangerous.

Baking soda toxicity most commonly causes nausea, vomiting, diarrhea, and stomach pain. Neurological symptoms like lethargy and drowsiness are less common.

In cases involving very large amounts, a person can develop metabolic alkalosis — a potentially life-threatening rise in the body's pH levels — which can cause strange sensations, involuntary muscle contractions, irregular heart rhythms, and temporary confusion. Skin exposure to large amounts of sodium bicarbonate can cause swelling, tissue death, and skin sloughing.

The vomiting and diarrhea that come with baking soda poisoning are the body's attempt to flush out excess sodium by pulling water into the digestive tract.

Bicarbonate also disrupts pH balance, which affects breathing as the body tries to hold onto carbon dioxide to restore normal acidity. On top of that, sodium bicarbonate reacts with stomach acid to produce carbon dioxide, leading to a buildup of gas.

In serious cases, baking soda toxicity can lead to seizures, kidney failure, coma, stomach tears, and spontaneous ruptures. Metabolic alkalosis can cause excess sodium in the blood or a buildup of carbon dioxide in the bloodstream. Many of these complications can be life-threatening.

Even safe amounts of baking soda can cause some mild side effects — bloating, gas, stomach cramps, and increased thirst. These typically develop as gas accumulates during the bicarbonate reaction and don't usually require medical attention.

If they persist or become painful, it's worth checking in with a healthcare provider.

If someone ingests a large amount of baking soda, contact Poison Control immediately. Don't induce vomiting unless Poison Control or a medical professional specifically advises it. If the person collapses, has a seizure, has trouble breathing, or is unresponsive, call emergency services right away.

To avoid poisoning, never substitute baking soda for sodium bicarbonate supplements — a teaspoon of baking soda contains roughly eight times more sodium and bicarbonate than a standard supplement. Always talk to a doctor before using baking soda as a self-treatment.

Some groups face a higher risk of serious harm from baking soda toxicity. People with alcoholism have higher rates of complications and death.

There are also case reports of pregnant women developing a compulsion to eat large amounts of baking soda — a condition that can produce symptoms resembling preeclampsia, including high blood pressure and organ damage.

Some pregnant people who overconsume baking soda develop rhabdomyolysis, a breakdown of skeletal muscle. People who take diuretics are also more vulnerable, as baking soda can push their sodium levels higher and potassium levels lower.

Despite the serious potential complications, treating baking soda poisoning is usually straightforward. IV fluid replacement is the most common approach, often paired with potassium supplements.

Irregular heart rhythms are corrected with electrolyte medications, given either intravenously or orally. Most people with metabolic alkalosis respond well to rehydration alone.

If blood pH levels are a concern, doctors may use hemofiltration or hemodialysis to restore the body's acid balance — or, in patients who can't undergo dialysis, administer hydrochloric acid directly.