What is the recommended treatment for an adult patient over 18 years old with androgenetic alopecia, considering the use of minoxidil (2% or 5% solution)?

Minoxidil Topical Solution for Androgenetic Alopecia

For adult men over 18 with androgenetic alopecia, apply minoxidil 5% topical solution 1 mL twice daily directly to the affected scalp area, and strongly consider combining it with platelet-rich plasma (PRP) injections for superior efficacy compared to minoxidil alone. 1, 2

First-Line Monotherapy Approach

Minoxidil 5% Application Protocol

• Apply exactly 1 mL of minoxidil 5% solution twice daily (morning and evening) directly to the dry scalp in areas of hair thinning 3
• Use the dropper applicator to ensure precise 1 mL dosing—squeeze the bulb, insert into bottle, release to fill to the 1 mL line 3
• Part hair and apply directly to scalp (not hair), spreading evenly over the treatment area 3
• Allow 4 hours of contact time before washing hair to maximize absorption 3
• Wash hands immediately after application if using fingers 3

Expected Timeline and Outcomes

• Initial results may appear at 2 months, but most men require at least 4 months of consistent twice-daily use before seeing meaningful regrowth 3
• Expect temporary increased shedding for up to 2 weeks when starting treatment—this indicates old hairs are being replaced by new growth 3
• Initial regrowth appears as soft, downy, colorless "peach fuzz" hairs that gradually become thicker and pigmented 3
• Hair regrowth has not been demonstrated beyond 48 weeks in large clinical trials, emphasizing the need for indefinite continuation 3
• Critical pitfall: Discontinuing minoxidil leads to complete reversal of hair growth benefits within months 1

Monitoring Response

• Evaluate treatment efficacy at 3,6, and 12 months using standardized photographs, trichoscopy for hair density/diameter assessment, and patient self-assessment questionnaires 4
• Monitor the terminal versus vellus hair ratio as a key indicator of treatment success 1
• A 25% improvement in hair density at 2 months predicts sustained response at 6 months 1
• If no improvement is seen after 4 months of consistent use, discontinue minoxidil monotherapy 3

Superior Combination Therapy Approach

Minoxidil 5% Plus PRP Protocol

The combination of topical minoxidil 5% with PRP shows significantly greater hair density improvement than either treatment alone and represents the most effective evidence-based approach. 1, 2, 5

• Apply minoxidil 5% topical solution 1 mL twice daily as described above 1
• Add PRP injections using the following protocol 1:
  • Treatment phase: 3-5 sessions spaced exactly 1 month apart
  • Dose: 5-7 mL of PRP per session, applied at 0.05 to 0.1 mL/cm²
  • Technique: Inject at 90-degree angle, 2-4 mm depth, with injections spaced 1 cm apart across the treatment area
  • Maintenance phase: 1 session every 6 months after completing initial treatment series

PRP Preparation Specifications

• Use manual double-spin method for PRP preparation 1
• Target platelet concentration: 1.0 to 1.5 million platelets per µL 1
• Do NOT activate PRP—nonactivated PRP shows 31% greater improvement in hair density compared to activated PRP 1
• Use 30G × 4 mm needles to minimize discomfort 1

Managing PRP-Related Discomfort

• Apply pharmaceutical-grade topical anesthetic cream before injection due to significant pain associated with the procedure 6, 1
• Patients should shampoo and detangle hair before the session with no hair products applied 1
• Expect transient pain during injection, with minimal bleeding and dizziness occurring in 15% and 5% of patients respectively 5

Combination Therapy Outcomes

• At 32 weeks, combination therapy (PRP + minoxidil) achieved 57% median increase in terminal hair density versus 48% with minoxidil alone 5
• 83% of patients achieve a negative hair pull test (indicating reduced hair fragility) with PRP combined with minoxidil 1
• Maximum response typically achieved by 6 months, with some patients requiring extended therapy beyond initial 6 months 1

Important Safety Considerations and Contraindications

Absolute Contraindications

• Women should NOT use minoxidil 5% solution—it works no better than 2% in women and may cause unwanted facial hair growth 3
• Do not use in pregnancy or breastfeeding 3
• Do not use in children under 18 years 3
• Avoid if scalp is red, inflamed, infected, irritated, or painful 3

Common Side Effects

• Scalp itching and dryness occurs in 75% of patients using topical minoxidil 5
• Pruritus, local irritation, and hypertrichosis (unwanted hair growth) occur more frequently with 5% versus 2% formulation 7
• If unwanted facial hair develops, stop use immediately—it will reverse over time 3
• Alcohol content causes burning if it contacts eyes—rinse immediately with large amounts of cool tap water 3

Serious Adverse Effects Requiring Immediate Discontinuation

• Stop use and seek medical attention if you experience 3:
  • Chest pain, rapid heartbeat, faintness, or dizziness
  • Sudden unexplained weight gain
  • Swelling of hands or feet
  • Persistent scalp irritation or redness

Flammability Warning

• Minoxidil solution is flammable—keep away from fire or flame 3
• Allow adequate drying time (2-4 hours) before going to bed to prevent transfer to pillows 3

Practical Application Tips

Compatibility with Hair Care Products

• Use mild shampoo if washing scalp before minoxidil application 3
• Hair sprays, mousses, conditioners, and gels may be used AFTER minoxidil has been applied and allowed to soak into scalp 3
• For hair coloring or perming 3:
  • Wash all minoxidil off hair and scalp before using chemical treatments
  • Do not apply minoxidil on the same day as chemical treatments
  • Wait 24 hours after chemical treatment before resuming minoxidil to ensure no scalp irritation
  • Missing one day will not affect overall results

Adherence Challenges

• Major pitfall: Real-world adherence is poor—one study found almost all patients gradually discontinued treatment due to low cosmetic effect and aversion to topical application method 8
• The insignificant cosmetic effect in some patients causes treatment discontinuation despite clinical efficacy 8
• Set realistic expectations: not everyone responds, and individual results vary significantly 3

Who Will NOT Benefit from Minoxidil

• Men with frontal baldness or receding hairline—minoxidil 5% is indicated only for vertex (crown) hair loss 3
• Men with more extensive hair loss than moderate vertex thinning—efficacy decreases with severity and duration of alopecia 1, 3
• Hair loss due to 3:
  • Medications (prescription or non-prescription)
  • Nutritional deficiencies (low iron, excess vitamin A)
  • Hypothyroidism
  • Chemotherapy
  • Scarring alopecia
  • Hair grooming trauma (tight cornrows, ponytails)
  • Patchy hair loss patterns

When to See a Doctor

• No family history of gradual hair loss 3
• Patchy or sudden hair loss 3
• Uncertain cause of hair loss 3

Storage and Handling

• Store at 20-25°C (68-77°F) 3
• Keep tightly closed 3
• Keep out of reach of children—if swallowed, contact Poison Control Center immediately (1-800-222-1222) 3