Abstract
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.