Hyperkalemia is the most common adverse event associated with spironolactone use in women, but is uncommon in women aged 45 years or younger, according to new research.

Dr. Shari Lipner, assistant professor, dermatology, Weill Cornell Medicine, New York

Dr. Shari Lipner

Spironolactone, which is approved to treat heart failure, hypertension, edema, and primary hyperaldosteronism, has antagonistic effects on progesterone and androgen receptors and has been used as an off-label treatment for acne in women. “Numerous guidelines have recommended its off-label use for acne therapy to avoid antibiotic resistance and potential side effects,” wrote Yu Wang of Stony Brook (N.Y.) University and Shari R. Lipner MD, PhD, of Weill Cornell Medicine, New York. Their report is in the International Journal of Women’s Dermatology.

In a retrospective study, the investigators analyzed 7,920 adverse events with spironolactone reported by women of all ages between Jan. 1, 1969, and Dec. 30, 2018, to the Food and Drug Administration’s Adverse Event Reporting System database, for all indications. The most common adverse event was hyperkalemia, reported in 16.1%, followed by kidney injury (15.2%) and drug interactions (9%). Of the 1,272 cases of hyperkalemia reported, 25 occurred in women aged 45 years or younger; 59.3% occurred in women aged 65-85 years.

While spironolactone prescribing information was not available, the investigators compared yearly reports of adverse events with annual public interest in spironolactone using the Google Trends search term spironolactone and annual scholarly mentions of spironolactone in the Altmetric database. There was a strong correlation between the number of cases reported to the FDA and the Google Trends search (Spearman coefficient, 0.94; P less than .001) and to the Altmetric database (Spearman coefficient, 0.64; P less than .01).

Noting that hyperkalemia is “exceptionally uncommon” in women aged 45 years and younger, the investigators concluded that “in the absence of risk factors for hyperkalemia or reduced renal function, potassium laboratory monitoring is unnecessary in younger females taking spironolactone.” Because the incidence increases with age, “interval laboratory monitoring is recommended for females older than 45 years old,” they noted.

Limitations of the study, they noted, include the retrospective design and no available data before 1969. “In addition, since the [FDA Adverse Event Reporting System] data does not differentiate whether spironolactone was prescribed for heart failure, hypertension, edema, primary hyperaldosteronism, or for acne,” the study could not control for these or other confounding comorbidities or associated therapies.

“For future studies, it is important to analyze drug interactions more carefully to determine which other medications may potentiate the risk for hyperkalemia in patients taking spironolactone. It is also important to quantitate overall U.S. prescription data to better understand the relative frequency of these adverse effects reported to the FDA,” they wrote.

The investigators reported that they had no conflicts of interest; the study had no funding.

SOURCE: Wang Y, Lipner SR. Int J Womens Dermatol. 2020 May 18. doi: 10.1016/j.ijwd.2020.05.002.