According to Dr. Sircus, baking soda, or sodium bicarbonate, taken at high doses can cause headaches, nausea and irritability. Muscle weakness, confusion, swelling of the feet and ankles, black tar-like stools and vomit that resembles coffee grounds are also negative effects caused by baking soda. Used as an antacid, baking soda can react with other medications, making it important to discuss all medicines and supplements being taken to a doctor.
Other more severe reactions to using baking soda include metabolic alkalosis, congestive heart failure, hyperosmolar syndrome, edema and hypertension due to increased sodium intake, according to Dr. Sircus. In most cases, serious side effects are a result of the administration of more than the recommended dosage of baking soda.
Discuss factors that increase the risk for serious side effects of baking soda use with a doctor before beginning treatment to lessen the chances of their occurrence, according to Dr. Sircus. Baking soda should not be used by people with pre-existing heart disease, kidney disease, liver disease, high blood pressure or allergies.
According to Dr. Sircus, it is important to only take the recommended dose of baking soda. Exceeding this dose neutralizes all the acids in the stomach, which triggers the stomach to produce more acid, exacerbating the symptoms of heartburn.