Topical minoxidil
Available over the counter in 2% and 5% concentrations, topical minoxidil is applied directly to the scalp once or twice daily. It works primarily by prolonging the anagen phase and increasing follicular blood flow. The 5% formulation shows modestly better results in clinical trials.
Low-dose oral minoxidil
Oral minoxidil (typically 1.25–5 mg daily) is prescribed off-label for hair loss. Systemic absorption means it reaches follicles more uniformly, which some studies suggest produces a more even response pattern — particularly for diffuse thinners.
Head-to-head comparison
Limited direct comparison data exist, but emerging retrospective studies suggest oral minoxidil may match or exceed topical efficacy, especially in patients who struggled with consistent topical application. However, oral formulations carry a wider side-effect profile including potential fluid retention and, rarely, cardiac effects at higher doses.
Practical considerations
Topical minoxidil can cause scalp irritation and leave residue; oral minoxidil avoids these local issues but requires periodic monitoring of blood pressure and heart rate. The choice depends on individual tolerance, adherence patterns, and clinician guidance.