Safety and tolerability of combination oral spironolactone and low-dose oral minoxidil for hair loss in adult females: A retrospective cohort study.

BACKGROUND

Spironolactone and oral minoxidil are effective female alopecia monotherapies. Combination therapy is commonly used, though safety and tolerability data are limited.

OBJECTIVE

To assess safety and tolerability by adverse effect incidence.

METHODS

Retrospective cohort study conducted in females aged ≥18 taking combination therapy for hair loss.

RESULTS

A total of 432 patients were included. Average spironolactone and low-dose oral minoxidil doses at time of adverse drug effects were 87.6 ± 51.4 mg and 1.8 ± 1.1 mg, respectively. Adverse effect incidence was 37.7% (n = 163). Hypertrichosis was most common (n = 53, 12.3%) followed by dizziness/lightheadedness/orthostasis (n = 52, 12.0%). Simultaneous initiation was observed to reduce hypertrichosis risk by 64.8% (odds ratio: 0.35; 95% confidence interval 0.13-0.94; P = .037). Concurrent use of ≥1 additional blood pressure-altering medications increased orthostatic effects risk (odds ratio: 3.29; 95% confidence interval: 1.65-6.58; P = .001). Dosage and treatment initiation pattern did not significantly increase risk of blood pressure effects. In 46.0% of cases, the therapeutic regimen was unmodified. When adjustments were made, they largely occurred in the outpatient setting (94.3%).

LIMITATIONS: Retrospective descriptive study lacking a control group.

CONCLUSION

Adverse effects from combination therapy are generally mild and managed outpatient. Concomitant use of ≥1 blood pressure-altering drugs increases risk of hypotension-related symptoms. Simultaneous initiation may reduce risk of hypertrichosis without increasing risk of hypotension-related effects.