What is the most common form of male‑pattern androgenetic alopecia and its first‑line therapy?

Male Pattern Baldness: Most Common Form and First-Line Treatment

Androgenetic alopecia presenting with temporal, vertex, and mid-frontal scalp thinning is the most common form of male pattern baldness, and combination therapy with oral finasteride 1 mg daily plus topical minoxidil 5% twice daily is the first-line treatment. 1

Clinical Pattern Recognition

The characteristic distribution involves:

• Preferential hair loss at temples, vertex (crown), and mid-frontal scalp with preserved occipital (back) and lateral (side) hair 1
• Progressive thinning over time rather than sudden patchy loss 1
• The Hamilton-Norwood classification documents extent of involvement 1

Critical distinction: If you observe patchy hair loss with "exclamation mark" hairs (short broken hairs at patch margins), this indicates alopecia areata—an entirely different condition requiring intralesional corticosteroids or contact immunotherapy, not finasteride/minoxidil. 2, 1

First-Line Pharmacological Treatment

Combination Therapy (Optimal Approach)

Initiate both medications simultaneously for maximal efficacy: 1

• Oral finasteride 1 mg once daily – inhibits 5-alpha reductase, blocking conversion of testosterone to dihydrotestosterone (DHT) 1
• Topical minoxidil 5% solution applied twice daily – promotes hair follicle growth through vasodilation and growth factor stimulation 1, 3

Expected Timeline and Outcomes

• Visible results require 2–4 months minimum, with optimal response at 12 months 3
• Treatment halts progression and stimulates partial regrowth in most patients 1
• Continuous lifelong use is mandatory—stopping either medication results in resumption of hair loss within months 1
• Initial shedding during first 2 weeks is expected and indicates old hairs being replaced 3

Monitoring Response

Use standardized photographs comparing baseline to follow-up at 3-month intervals initially, then every 6–12 months 1

Second-Line and Adjunctive Options

Platelet-Rich Plasma (PRP) Injections

For suboptimal response to finasteride/minoxidil combination: 1

• Treatment phase: 3–5 sessions at exactly 1-month intervals using 5–7 mL PRP per session 1
• Maintenance phase: 1 session every 6 months indefinitely 1
• Injections administered at 90-degree angle, 2–4 mm depth, 1 cm apart across affected areas 1
• Evidence shows increased hair density and count when added to medical therapy 1

Hair Transplantation

Consider follicular unit extraction for patients with inadequate response to medical therapy, especially when combined with PRP pre-treatment 1

Common Pitfalls to Avoid

• Do not delay effective treatment with unproven supplements (e.g., saw palmetto lacks robust evidence)—irreversible follicle miniaturization may occur 1
• Do not use potent topical corticosteroids for androgenetic alopecia; they are ineffective and indicated only for alopecia areata 2, 1
• Do not stop treatment prematurely if results are not visible by 2 months; minimum 4-month trial is required 3
• Do not confuse with alopecia areata—patchy loss with exclamation mark hairs requires entirely different management 2, 1

Contraindications and Cautions

Finasteride is contraindicated in women of childbearing potential due to teratogenic risk 1

Minoxidil 5% is FDA-approved only for men; women should use 2% formulation 4, 3

Patients should be counseled about potential sexual side effects with finasteride (reported in clinical trials but controversial regarding true incidence) 5

Alternative Formulations Under Investigation

Topical finasteride 0.25% daily and oral dutasteride 0.5 mg show promise with potentially fewer systemic effects, though not yet FDA-approved for this indication 5