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Do Not Use! The Water Pill (diuretic) Indapamide (LOZOL) for High Blood Pressure

Worst Pills, Best Pills Newsletter article January, 2003

The August 2002 issue of the Australian Adverse Drug Reactions Bulletin reviewed reports of low blood levels of sodium (hyponatremia) induced by the water pill, or diuretic, indapamide (LOZOL). The main symptoms of hyponatremia involve the central nervous system and include lethargy, confusion, stupor, or coma.

Indapamide was first marketed in Australia in the mid-1980s and is the drug most commonly implicated in causing hyponatremia with 164 cases being reported to the Australian...

The August 2002 issue of the Australian Adverse Drug Reactions Bulletin reviewed reports of low blood levels of sodium (hyponatremia) induced by the water pill, or diuretic, indapamide (LOZOL). The main symptoms of hyponatremia involve the central nervous system and include lethargy, confusion, stupor, or coma.

Indapamide was first marketed in Australia in the mid-1980s and is the drug most commonly implicated in causing hyponatremia with 164 cases being reported to the Australian authorities. Of these 164 reports, 68 also described low blood levels of potassium (hypokalemia). Over half (92) of the reports described symptoms including confusion, nausea, vomiting, dizziness, loss of appetite, malaise, fatigue, fainting, somnolence and convulsions. Most patients, 88 percent, were 65 years or over and 82 percent were female.

Indapamide was approved in the U.S. in July 1983. Our search of the Food and Drug Administration’s (FDA) adverse drug reaction database through the first quater of 2002 found 222 reports of hyponatremia associated with the use of indapamide. The FDA conservatively estimates that for each adverse reaction reported ten go unreported.

The Australian authorities recommend that indapamide should be used cautiously and changes in conscious or mental state should prompt measurement of the blood sodium concentration. Our advice is that indapamide should not be used.

We can think of no reason why a patient should be placed at risk of developing hyponatremia when more effective, safer water pills that are less likely to cause hyponatremia are available to treat high blood pressure such as hydrochlorothiazide (HYDRODIURIL).

If you have high blood pressure, the best way to reduce or eliminate your need for medication is by improving your diet, losing weight, exercising, and decreasing your salt and alcohol intake. If these measures do not lower your blood pressure enough and you need medication, hydrochlorothiazide is the drug of choice starting with a low dose of 12.5 milligrams daily. It also costs less than other blood pressure drugs.

What You Can Do

If you are taking indapamide for high blood pressure, you should ask your doctor why you have not been prescribed hydrochlorothiazide.