Routine serological results of a couple who drank green tea for 40 years revealed hypokalemia.
Besides the well-known and widely advertised benefits of green tea, is the general population aware of the other side of the picture? Can green tea cause electrolyte imbalances? Here are two patients with green tea consumption and hypokalemia!
A couple presented to the clinic for a regular check-up. The husband was a 73-year-old man with a medical history of hypertension. His wife was a 67-year-old woman with a medical history of diabetes and hypertension. However, she successfully controlled her diabetes with dietary restrictions.
The husband’s usual medications included amlodipine 5 mg, lisinopril 10 mg, bendroflumethiazide 2.5 mg, and 40 mg atorvastatin. His wife’s regular medications included amlodipine 5 mg, lisinopril 20 mg, and simvastatin 20 mg.
Both of them were otherwise healthy and had no active complaints. Both were non-smokers and avoided alcohol consumption. However, the couple would enjoy approximately eight cups of Vietnamese green tea a day, each of 300 mL. they had been drinking the green tea for the past 40 years regularly.
Routine investigations of the husband and wife revealed decreased serum potassium levels with results of 3.1 mmol/L and 3.2 mmol/L, respectively.
Since the husband was on bendroflumethiazide therapy, the doctors suspected it to be the cause of hypokalaemia as thiazides may decrease serum potassium levels. However, the mystery of hypokalemia in the wife remained unsolved.
The doctors advised the husband to discontinue bendroflumethiazide. Moreover, the doctors also advised the couple to decrease green tea consumption.
Both of them reduced the green tea intake to half, alternating each cup of tea with a glass of water.
After a month husband’s potassium level increased to 4.4 mmol/L. Similarly, his wife’s serum potassium had also improved to 3.7 mmol/L.
Green tea and hypokalemia:
The actual link between green tea and hypokalaemia is yet it be explored. However, theophylline in green tea may lead to decreased potassium levels.
Therefore, it is safe to say that although green tea may have a set of benefits, excessive consumption of it can lead to complications and electrolyte imbalances. Moreover, this case also reflects the importance of dietary history while managing patients with electrolyte imbalances.
Chong SJ, Howard KA, Knox C. Hypokalaemia and drinking green tea: a literature review and report of 2 cases. BMJ Case Rep. 2016;2016:bcr2016214425. Published 2016 Feb 16. DOI:10.1136/bcr-2016-214425