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Microneedling

Evidence
73%
Regrowth
Viability
  • Therapy
  • Microneedling
    Evidence Quality

    73%

    Regrowth Potential
    Long-Term Viability
    Written by Perfect Hair Health Team
    Medically Reviewed by Rob English
    First Published Oct 6, 2024
    Last Updated Oct 24, 2024

    Key Information

    Free Resources

    KEY INFORMATION

    What Is Microneedling?

    Microneedling is a therapy that involves the deliberate and repeated wounding of skin – often at depths of 0.25mm to 5.0mm. It can be administered at-home or by a medical professional.

    How Does Microneedling Work?

    Microneedling is believed to work through mild acute inflammation, which then releases growth factors that may improve skin scarring, increase angiogenesis (new blood vessel networks), and initiate new hair cycles.

    What You Should Know

    Research on microneedling is limited. However, clinical studies currently suggest that microneedling appears to enhance hair growth, and that it might enhance the hair growth-promoting effects of other topicals – such as minoxidil – by up to 400%.

FREE RESOURCES

Articles

Explore the science behind hair loss and hair growth. Our in-depth articles cover topics ranging from natural remedies to pharmaceuticals to breakthroughs in hair loss science. Want to request an article topic? Contact us.

Microneedling the Scalp: Does it Cause Scarring?
By Sarah King, PhD
May 31, 2024

Microneedling the Scalp: Does it Cause Scarring?

Can repeated microneedling on the scalp cause scarring? There aren’t yet long-term studies answering this question. On the one hand, microneedling increases neocollagenesis (i.e., the formation of new collagen, or skin tissue). On the other hand, studies show that microneedling-induced collage...
Why Am I Shedding After Microneedling?
By Perfect Hair Health Team
Apr 25, 2024

Why Am I Shedding After Microneedling?

Temporary hair shedding is commonly reported after men & women start hair loss treatments like minoxidil. But is temporary hair shedding also normal when starting microneedling? On the one hand, microneedling induces acute inflammation. A little inflammation might benefit hair growth, while too ...
What Happens If I Stop Microneedling?
By Sarah King, PhD
Apr 19, 2024

What Happens If I Stop Microneedling?

In general, treatments for hair loss are only effective as long as they are continued. However, limited data suggests that microneedling may exert its effects up to six months post-treatment (with or without minoxidil). In this article, we will dive into the research behind how long the positive hai...
Is Hair Loss Treatment Lifelong? Here’s What The Data Show.
By Sarah King, PhD
Apr 11, 2024

Is Hair Loss Treatment Lifelong? Here’s What The Data Show.

It can be daunting to think of hair loss treatments as a lifelong commitment. And for most cases of androgenic alopecia, this is true. However, starting treatment does not necessarily mean you must commit to a lifetime of treatment. Studies suggest that after stopping a hair loss treatment, hair los...
Microneedling vs PRP: Which Is Better?
By Perfect Hair Health Team
Apr 11, 2024

Microneedling vs PRP: Which Is Better?

Dermatologists often recommend platelet-rich plasma therapy (PRP) as a treatment for hair loss. However, studies suggest that microneedling might also achieve the same results for a fraction of the price.  This article provides a comprehensive comparison of PRP versus microneedling: the clinical evi...
Am I Supposed to Bleed When Microneedling? A Scientific Analysis
By Perfect Hair Health Team
Apr 11, 2024

Am I Supposed to Bleed When Microneedling? A Scientific Analysis

Microneedling is an experimental hair loss intervention that creates tiny punctures on the scalp skin surface – which improves topical penetration and triggers the body’s natural healing response. During a microneedling session, it’s normal to experience a bit of pinpoint bleeding. Havin...
Microneedling Infection: Is the Scalp at Risk?
By Perfect Hair Health Team
Jan 10, 2023

Microneedling Infection: Is the Scalp at Risk?

Microneedling is a popular way to combat hair loss and promote hair growth. It creates low levels of inflammation in the scalp tissue, which triggers an adaptive response in the body; growth factors and signaling proteins are recruited for wound repair. However, as with any wound (no matter how smal...
Microneedling For Hair Loss: 5 Strategies to Reduce Pain
By Perfect Hair Health Team
Sep 16, 2022

Microneedling For Hair Loss: 5 Strategies to Reduce Pain

Microneedling is an experimental therapy for androgenic alopecia and other hair loss disorders. One of its downsides is that it is painful to administer. However, there are simple and effective strategies to reduce pain levels while microneedling across the scalp:(1) opting for devices that ensure n...
Mature Hairline vs Receding: How to Tell the Difference
By Perfect Hair Health Team
Apr 10, 2022

Mature Hairline vs Receding: How to Tell the Difference

It can be difficult to distinguish between a mature hairline and a receding hairline. After all, hairline changes are a natural part of the aging process. What key characteristics separate hairline maturation from outright recession? This investigative post will explain 1) How to identify a mature h...
How Long After Stopping Minoxidil Before We Lose Our Hair Gains?
By Perfect Hair Health Team
Mar 10, 2022

How Long After Stopping Minoxidil Before We Lose Our Hair Gains?

Studies show that within 3 months of quitting minoxidil, any new hair growth is lost and, worryingly, our hair loss temporarily worsens before returning to baseline. But encouragingly, new studies are revealing potential ways to mitigate any shedding related to minoxidil withdrawals. In fact, a 2020...
Three Ways to Improve Minoxidil Results
By Perfect Hair Health Team
Mar 5, 2022

Three Ways to Improve Minoxidil Results

Minoxidil is one of the most widely used hair loss products on the market. And yet, so much about this growth activating “pro-drug” remains unknown. Despite its FDA approval, results are not guaranteed. In fact, around 50% of hair loss sufferers are non-responders. Recent research sugges...
Scarring Alopecias: What Makes Them Unique (And Reversible)
By Perfect Hair Health Team
Jul 2, 2020

Scarring Alopecias: What Makes Them Unique (And Reversible)

Scarring alopecias were once thought to be irreversible. Now, studies are proving just the opposite. Case reports are showing that people with scarring alopecias have experienced complete hair regrowth, and from changes as simple as quitting sunscreen. Read on to learn the science behind these scarr...
Microneedling For Hair Loss: Daily, Weekly, Or Bi-Weekly?
By Perfect Hair Health Team
Jan 16, 2020

Microneedling For Hair Loss: Daily, Weekly, Or Bi-Weekly?

Clinical studies show that microneedling once every 1-3 weeks helps to regrow hair. Then again, 1-3 week intervals are the only frequencies studied for pattern hair loss. With men on hair loss forums reporting amazing results from microneedling as often as once per day, could we be missing something...
Microneedling For Hair Loss: What’s The Best Needle Size?
By Perfect Hair Health Team
Jan 7, 2020

Microneedling For Hair Loss: What’s The Best Needle Size?

When it comes to microneedling for hair regrowth, researchers aren’t yet sure which needle size elicits the best results. In clinical studies, needle lengths of 0.6mm to 2.5mm (used once weekly or bi-weekly) have been shown to improve hair counts in men with androgenic alopecia (AGA). Even sti...
  • FREE RESOURCES

    Research Tables

    Want the latest research on Microneedling? Every quarter, our research team conducts a literature search on Microneedling to keep you up-to-date on new studies. See our search criteria & research tables below – including a summary of key findings from every single study.

    Last updated: October 2024

    Results

    Search Criteria

    Parameter
    Inclusion Criteria
    Exclusion Criteria
    PatientsPatients of any age treated for scalp hair loss.Patients with no hair loss disorder.
    InterventionMicroneedling as a standalone or adjunct therapy.Acupuncture needles or microneedling devices with needle-releasing drugs.
    ComparatorPlacebo and/or other therapies or baseline.No comparator.
    OutcomesPrimary Endpoints of phototrichogram, investigator, and/or patient assessments.Any study not designed to adequately test for the standalone or additive effect of microneedling.
    Study DesignProspective studies.Literature reviews, non-human subjects, or ongoing clinical trials.

    Search Terms

    Search Terms:
    microneedling areata hair loss cicatricial effluvium microneedle alopecia
    • Abbreviations:
    • FPHL
      Female pattern hair loss
    • AGA
      Androgenetic alopecia
    • AA
      Alopecia areata
    • MX
      Minoxidil
    • MN
      Microneedling
    • PRP
      Platelet-rich plasma
    • TA
      Triamcinolone acetonide
    • MXT
      Topical minoxidil
    • AU
      Alopecia Universalis
    • AT
      Alopecia Totalis
    • AASIS
      Alopecia Areata Symptom Impact Scale
    • SALT
      Severity of Alopecia Scoring Tool
    • FGF
      Fibroblast growth factor
    • SPT
      Spironolactione
    • LAD
      Lesional Hair and Density Score

    Summarized Studies

    StudyParticipantsDesignTreatmentResultsKey TakeawayAdverse EffectsEq
    Authors (year)SexHair Loss TypeDesignTreatment TypesTreatment RegimenMN ProcedureNo. of SessionsDurationEndpoints

    		Hair Growth AssessmentsSummary

    		Limitations
    		Adverse EffectsJadad Score
    Zhang et al (2022)n=40 (F)
    Group 1 = 20
    Group 2 = 20    		iconFPHLSingle-center, randomized, controlled, evaluator-blinded clinical trial.2% MXT and MN.Group 1: 2% MXT alone.
    Group 2: 2% MXT + MN.    		MN length of 260 μm. Two passes until the scalp becomes reddish. 2% MX was then applied.Group 1: twice daily
    Group 2: twice daily MXT with once weekly MN.    		24 weeksInvestigator assessment of hair growth and change from baseline hair counts.Effective rate in Group 2 was 85% which was significantly higher than that of Group 1(45%). Hair counts were also higher in the combined treatment group.MN combined with MXT had better efficacy for FPHL during treatment and follow-upSmall sample size, single-center study, lack of placebo control, short-follow-up period.Group 1: Hirsutism = 3
    Scalp itching and transient increase in hair loss = 7
    Group 2: Occasional headache = 2
    Hirsutism = 10
    Scalp itching and transient increase in hair loss = 1
    2
    El Mulla et al (2022)n=60
    Group 1: 15 (M:6, F:9)
    Group 2: 15 (M:9, F:6)
    Group 3: 15 (M:6, F:9)
    Group 4: 15 (M:10, F:5)    		iconAAInterventional, comparative study.Fractional carbon dioxide laser, TA, MN and PRP.Group 1: Fractional carbon dioxide laser + TA (10 mg/mL).
    Group 2: MN and TA (10 mg/mL).
    Group 3: Fractional carbon dioxide laster + PRP.
    Group 4: MN + PRP.    		Dermapen with a 36-needle tip 2 - 2.5 mm long needle depth used until pinpoint bleeding or mild erythema occurred.Every 3 weeks.12 weeks with a follow-up four weeks later.Hair regrowth assessment (SALT scores), improvement scores, and dermascopic changes.At the four-week follow-up: 80% of patients in group 2 improved SALT score to 0 (no hair loss), whereas group1 and group 4 improved by 40%. Group 3 improved only 13.3%.
    Hair regrowth scores showed that group 2 showed maximum improvement with 80% of patients scoring RGS5.
    		Overall, the MN + TA group showed the most significant improvement.Small sample size, no blinding.No major complications were observed, but heat discomfort was reported during CO2 laser procedures.
    2
    Abdallah et al (2022)n=20
    M:19
    F:1
    		iconAAProspective, intra-patient controlled study.TA, MX, MN or nothing.Patch 1: Intralesional TA.
    Patch 2: intradermal MX.
    Patch 3: Combined intradermal TA + MX.
    Patch 4: MN.
    Patch 5: Negative control.    		ZGTS Titanium derma roller. 4-5 passes longitudinally, vertically, and diagonally.Every four weeks16 weeksSALT score and lesional area density (LAD) score. Trichoscopy and photographic documentation to evaluate treatment response.SALT and LAD scores decreased in patches 1, 2, 3, and 4; the largest differences were seen in patches 1 and 3 vs. patch 5.Intradermal injection did not show significant superiority over spontaneous regrowth in patchy non-severe AA suggesting that microneedling may be a comparable option.Short treatment duration, small sample size.Mild burning pain reported during the procedure, but treatment was generally tolerable.

    No serious adverse events recorded.
    2
    Abd ElKawy et al (2022)n=30
    (M:18, F:12)
    		iconAAProspective, split-side, comparative study.Fractional CO2 laser, TA, and MN.Side 1: Fractional CO2 laser + TA.
    Group 2: MN + TA.    		Side 2: 12-needle cartridge at a depth of 1.5 mm until pinpoint bleeding and erythema were observed.Every four weeks.24 weeksClinical response, efficacy and safety, dermoscopic imaging, and SALT score.Side 1: 56.7% achieved complete response, 23.3% partial response, and 20% no response.
    Side 2: 86.7% achieved complete response, 6.7% partial response, and 6.7% no response.
    Side 2 showed better clinical response and SALT score improvement. Dermoscopic signs improved significantly in both groups. Duration of AA influenced response and no. of sessions needed for improvement.
    		While both treatments proved effective for treating AA, MN demonstrated better results and was more tolerable. Small sample size, not controlled, short follow-up period.Mild pain and erythema in a few patients.
    3
    Muhammad et al (2022)n=60
    Group 1: 30 (M:27, F:3)
    Group 2: 30 (M)    		iconAGARandomized, observational, interventional study.PRP and MN.Group 1: P
    RP alone.

    Group 2: MN + PRP    		Group 2: derma roller with needles measuring 2 mm until erythema and pinpoint bleeding were observed. PRP was then applied.Every four weeks12 weeksPhotographs of the scalp, hair pull test to assess hair loss, hair count in a predefined 1 cm2 area of the scalp, and patient-reported levels of satisfactions using a Likert scale.Negative Hair Pull Test:
    Group 1:     51.9%, Group 2: 82.1%.
    Improved Perception of Hair Loss: Group 1:73.9%
    Group 2: 88%.
    % increase in hair count:
    Group 1:     17.88±10.15%, Group 2: 24.53±9.49% (p = 0.011).     		MN + PRP was found to have better treatment outcomes, increased hair count, and lower pain perceptions compared to PRP alone. Patients receiving combined treatment reported higher satisfaction and lower pain scores. The combined approach may offer improved treatment success rates, patient satisfaction, and compliance.Small sample size, underrepresentation of female participants, no control group.None mentioned.
    1
    Arora et al (2022)n=60iconAGAProspective, randomized, comparative study.MN and TAGroup 1: MN with local application of injectable TA.
    Group 2: Injectable TA administered intradermally.    		Group 1: dermaroller of needle size 1.5 mm was moved on the scalp patches 4-5 times in each direction until pinpoint bleeding was observed.
    Group 2: Intradermal injections of 10 mg/mL TA with a disposable insulin syringe.    		Once every 3 weeks9 weeksClinical examination, area measurement of patches, regrowth evaluation, uniformity of regrowth, and adverse effects.Both groups showed significant regrowth. Group 1: exhibited mean regrowth of 66.36% at week 9.
    Group 2: exhibited mean variegated regrowth of 69.75% at week 9.     		Injectable TA used with MN and intralesionally has similar efficacy in promoting hair regrowth in AA. MN resulted in more uniform but less dense regrowth.Small sample size, short follow-up, lack of patient feedback evaluationGroup 1: Tinea infection = 1.
    Group 2: Hypopigmentation = 2.
    2
    Liang et al (2022)n=120 (F)
    Group 1 = 38
    Group 2 = 37
    Group 3 = 40    		iconFPHLProspective, single-cente, parallel-group, evaluator blinded, randomized trial.MXT, spironolactone (SPT), and MXT + MN.Group 1: 5% MXT.
    Group 2: 80-100mg SPT + 5% minoxidil.
    Group 3: 5% MX + MN    		Electrodynamic microneedling inserted at a depth of 0.7 - 1 mm until pinpoint bleeding was observed.Group 1: Once daily.
    Group 2: Once daily.
    Group 3: Topical MX once daily plus MN every 2 weeks.    		24 weeksHair growth, scalp tissue structure, physician and patient assessments, and side effects.MXT + MN group showed the most increased hair density (99.68±15.58 - 130±20.58) and MXT showed the least (101.37±17.32 - 111.32±19.57).
    Hair shaft diameter significantly increased in all groups. Epidermal thickness and average hair follicle diameter increased only in the MXT + MN group. Dermis thickness increased in all groups. Both physician’s and patient’s assessments showed improvement in all three groups.
    		The combination of MXT and MN was found to be the most effective choice for treating mild-to-moderate FPHL in women with regular menstrual cycles and normal hormone levels, compared to either MX plus SPT or MX alone.Severe FPHL patients (Sinclair IV and V) were excluded. Unblinded.Group 1: facial hypertrichosis=4, trichomadesis aggravating=4, scalp pruritus=8, increased scurf=7, headache=1, palpitation=1, postural hypotension=1, urticaria=1.
    Group 2: facial hypertrichosis=5, trichomadesis aggravating=4, scalp pruritus=8, increased scurf=6, edema=1, headache=1, palpitation=3, hyperkalemia=1, menstrual disorder=15, urticaria=1.
    Group 3: facial hypertrichosis=5, trichomadesis aggravating=3, scalp pruritus=9, increased scurf=5, infection=1, postural hypotension=1.
    4
    Ozcan et al (2022)n=62 (M)iconAGARandomized, controlled trialPRP, MN and point-by-point injection.Group 1: PRP + MN
    Group 2: PRP + point-by-point injection    		Group 1: 1.5 mm MN.
    Group 2: 30 gauge, 5 mm syringe.    		3 sessions every 2 weeks initially and then a fourth session 1 month later10 weeksTrichoscan analysis, hair pull test, and patient/physician global assessment scoresBoth PRP applications showed significant improvements in hair growth parameters (hair count, density, anagen/telogen ratio, and hair length). Hair pull test became significantly negative in both groups, indicating reduced hair loss. Patient and physician satisfaction scores were high in both groups. Whilst both groups showed significant improvements in hair growth parameters, PRP + MN was found to be superior in certain aspects.The lack of a placebo group and limited follow-up period.None mentioned.
    1
    Bao et al (2022)n=71 (M)
    Group 1: 23
    Group 2: 23
    Group 3: 25    		iconAGARandomized, controlled trial.5% MXT, and electrodynamic MN treatment Group 1: 5% MXT
    Group 2: Electrodynamic MN
    Group 3: Combination MXT and MN.    		Groups 2 and 3: MN device inserted at a depth of 1-2 mmGroup 1: Applied twice daily.
    Group 2: MN every 3 weeks.
    Group 3: MXT twice daily + MN every 3 weeks.     		24 weeks + 24 weeks follow-upPhototrichography to measure growth, thickness and density. Evaluation every 3 weeks and details of any toxicities related to treatments were collected.All three groups showed a significant increase in non-vellus hair density after treatment. Group 3: showed the highest increase in non-vellus hair density (22.46±3.87). Group 3: showed the more superior final hair density (39.78±7.79). Vellus hair density decreased in groups 1 and 3 after treatment, but not in group 2. Final hair diameter increased significantly in groups 1 and 3.
    Follow up: Group 3: maintained the increased hair density. Group 1: Hair loss recurred.
    		MN combined with MXT can effectively treat AGA and promote hair growth.Small sample size, only the combination group received scalp massages after treatment, which may confound the results.Group 1: seborrheic dermatitis, scalp itching, and eczema.
    Group 2: increased dandruff, scalp infection and enlarged lymph nodes.
    Group 3: seborrheic dermatitis, increased dandruff, and enlarged lymph nodes.
    3
    Aboeldahab et al (2021)n=80
    Group 1: 40 (F:16, M:24)
    Group 2: 40 (F:14, M:26)    		iconAAProspective, randomized, single-blinded trial.Superficial cryotherapy + MNGroup 1: Superficial cryotherapy
    Group 2: MN    		Dermapen for 4-5 passes in each direction. Needle range from 1-2 mm. Every 2 weeks.12 weeks with follow-up 12 weeks later.SALT score, trichoscopy, AASIS for patient self-assessment.Both treatments showed improvements in the SALT score and hair density. Group 2 showed slightly better results in terms of SALT score change and hair density change percentages. Good to excellent responses were achieved in both groups, with microneedling showing a slightly higher rate of success. No recurrence of AA was observed in responders of either group during the follow-up period.Both superficial cryotherapy and MN are effective and well-tolerated options for mild scalp AA. MN demonstrated slightly better efficacy.Only mild AA cases used, with no control group.Transient adverse effects were reported in the cryotherapy group, while the MN group did not report any significant side effects.
    3
    Burns et al (2021)n=11 (F)iconFPHLPilot, interventional study.Combination 5% MXT + MN added to ongoing hair loss treatments.Combination 5% MXT + MN added to ongoing hair loss treatments.MN automated pen, session endpoints marked as two passes across the frontal, crown, vertex, and upper-parietal scalp.Every 2 weeks.12 weeksPhotographic evaluation, self assessmentsInvestigators noted that 11/11 subjects improved at lease 1-1,5 Sinclair scores.Combination MXT + MN appears to be an effective treatment for FPHL.Small sample size, no placebo or comparator, short study length.Transient headache, pinpoint bleeding, and mild erythema.No serious adverse events were reported.
    1
    Ramadan et al (2021)n= 126
    (M:46,
    F:80)
    Group 1: 42.
    Group 2: 42
    Group 3: 42    		iconAGASingle-blind, randomized, controlled study.Combination PRP, 5% MXT, 2.5 mg finasteride (men), 200 mg SPT (women)Group 1: medications + PRP injections
    Group 2: medications + MN + topical PRP
    Group 3: medications alone.    		MN automated pen, 2 mm needles, session endpoints marked as 3 passes followed by PRP.Once monthly

    		24 weeks.

    		Hair counts, diameters and photographic evaluation.Hair density increased in Group 2 vs. Group 1; larger effect for Groups 1 and 2 versus Group 3.Combination of MN, medications and topical PRP appear to be more beneficial for hair growth in people with AGA.Lack of devices to measure trans-epiermal delivery of growth factors in PRP. No serious adverse events were recorded. Transient pain after PRP = 23
    2
    Gowda et al (2021)n= 90
    Group 1: 30
    Group 2: 30
    Group 3: 30    		iconAGAProspective, comparative, parallel-group interventional study.MXT, MN, and PRPGroup 1: MXT alone.
    Group 2: MXT + MN.
    Group 3: MXT + PRP.    		1.5 mm sized needles were used until pin point bleeding was obseerved.Group 1: twice daily.
    Group 2: twice daily MXT with MN once monthly.
    Group 3: twice daily MXT with PRP once monthly.    		16 weeks.Investigator assessment (5-point scale), global phtoographic assessment (7-point scale), and visual andalogue scale (VAS).
    Hair counts and dermascopic analysis.
    		Dermoscopic analysis showed maximum improvement in group 3 (64.37±14.42 - 86.13±14.82), followed by group 2 (69.30±17.97 - 85.73±23.10)While PRP + MXT showed the highest efficacy, it also showed the highest number of adverse effects. Therefore, it may be more beneficial to use MN + MXT.Short study duration.Side effects reported including pain, erythema, burning, and edema. Group 3 reported more side effects than the other groups.
    2
    Shome et al (2021)n=50
    (M:25, F:25)
    Group 1: 25
    Group 2: 25    		iconAGAComparative, prospective, single-blind study.Intradermal injection of QR678Neo and QR678Neo + MN.Group 1: Intradermal injection of QR678Neo.
    Group 2: MN and then QR678Neo.    		Group 1: 60 - 70 small injections with 6 mm, 31G needle administered at a depth of 1-2 mm intradermally by nappage technique.
    Group 2: Dermaroller with 1.5 mm needle size passed approx. 4-5 times until erythema was observed.    		Once every 3 weeks.24 weeks + 24 weeks of follow-upHair counts, diameters, photographic evaluation, and self-assessment.Hair counts and diameters increased in both groups. However, there was no significant difference between the groups. Whilst there is no significant difference between groups, intradermal injection did appear to show a slightly better outcome in both patient self-assessment and in hair counts.Small sample size, no placebo.Group 1: uncomfortable pain.

    Group 2: uncomfortable pain.
    Itchy scalp.
    Erythema.
    2
    Ragab et al (2020)n=60
    Group 1: 20 (F:2, M:18)
    Group 2: 20 (F:6, M:14)
    Group 3: 20 (F:4, M:16)    		iconAARandomized, non-controlled study.PRP, fractional laser therapy, and MN.Group 1: Intradermal PRP injection.
    Group 2: fractional laser therapy + topical PRP. Group 3: MN + topical PRP.    		Dermaroller with 1.5 mm needles was used until mild erythema appeared.Every 4 weeks.12 weeks.SALT score, and patient satisfaction. Pain during procedures was evaluated using a numeric pain rating scale.All groups showed varying degrees of improvement after treatment sessions. Patients who experienced improvement maintained their progress without recurrence. Pain scores were significantly lower in groups 2 and 3.PRP delivered through each method may benefit hair regrowth in AA patients. MN has the additional advantage of being less costly than fractional laser therapy.Variation in patient response, and even between lesions, short follow-up period and absence of a control group.Pain during procedures was reported, but other side effects were minimal.
    2
    Giorgio et al (2020)n=41
    (M:17, F:24)
    		iconAARandomized studyMN aminolaevulinic acid (ALA), and photodynamic therapy (PDT)Group 1: MN alone using an electronic pen device.
    Group 2: 10% ALA-PDT.
    Group 3: Combination MN and ALA-PDT.    		Electronic MN pen with 1 mm penetration.Every 3 weeks.18 weeks.% of hair regrowth in treated areas. Evaluation using a 4-point scale.Group 3 showed the best clinical outcomes. Complete hair regrowth was observed in 3 patients, ≥50% improvement in 7 patients and <50% improvements in 6 patients. Group 1 showed no improvement. Group 2 showed varying responses, with some achieving improvement.Combination therapy with ALA-PDT and MN yielded better results for AA compared to individual treatments.A small sample size.Not specified.
    1
    Sohng et al (2020)n=29 (M:24, F:5)
    Group 1: 11
    Group 2: 9
    Group 3: 9    		iconAGARandomized, parallel-group, 6-month prospective study.Home-use MN and 5% MXT.Group 1: Home-use MN alone.
    Group 2: Home-use MN + 5% MXT.
    Group 3: 5% MXT alone.    		0.25mm long spiral grooved MN.Group 1: twice weekly
    Group 2: twice weekly + twice daily
    Group 3: twice daily.     		24 weeks.Hair counts and self-assessments.The patient self-assessment score was higher in Group 2 than in the other 2 groups. However, a statistically significant increase in hair count was not seen in any of the groups compared to the baseline.Whilst combination treatment of MN and MXT510 appeared to lead to better outcomes, there were not statistically significant improvements.Small sample size, small hair count area.No serious adverse events were recorded. Mild and transient pruritus noted in one subject.
    2
    Yu et al (2020)n=40 (M)
    		iconAGARandomized controlled trial.Combination: 5% MX, growth factors.Group 1: Nano-MN-assisted normal saline.
    Group 2: 5% topical MX.
    Group 3: Nano-microneedle-assisted fibroblast growth factor (FGF).
    Group 4: Combination of 5% topical MX and nano-MN-assisted FGF.    		Microneedle roller.Once weekly.16 weeks.Hair counts, hair diameters, photographic evaluation, self assessments.Hair density significantly increased in groups 2, 3, and 4. Hair diameter significantly improved in groups 2 and 4. Follicular unit density significantly improved in groups 3 and 4. Group 4 showed the most satisfactory results in terms of hair density, diameter and follicular unit density.Combination nano-microneedle assisted FGF and topical minoxidil was safe and effective at treating AGA, resulting in improvements in hair density, diameter, and follicular unit density.Small sample size, short-term study.No serious adverse events were recorded. Three subjects developed mild erythema, which alleviated after 24 hours.
    3
    Aggarwal et al (2020)n=30 (M)iconAGARandomized, triple-blinded cohort study.MN and PRP.Group 1: MN alone.
    Group 2: MN combined with PRP.    		MN roller: 1.5-2 mm needles with session endpoints marked as gentle rolling until pinpoint bleeding.Once monthly.24 weeks.

    		Hair counts, hair diameters, self-assessments.Hair thickness and density increased in both groups 1 and 2, but there was no significant difference between the 2 groups. Patient’s subjective satisfaction scores indicated moderate satisfactions, with most patients reporting a reduction in hair fall. Both treatments were well-tolerated, with mild tingling and aching pain as the most common adverse effects.While combination treatment may provide some benefits in treating AGA, the improvement was not significant enough to make it a preferred choice over microneedling alone.Small sample size, need longer-term follow up.No serious adverse events were reported.
    3
    Fagihi et al (2020)n=60 29 - M
    31 - F
    		iconAGARandomized, controlled trial.5% MX and MNGroup 1: 5% MX
    Group 2: 5% MX + MN
    Group 3: 5% MX + MN     		Group 2: 1.2 mm needles.
    Group 3: 0.6 mm needles.    		Once every 2 weeks.12 weeks.Hair counts, hair diameters, photographic evaluation, and patient self-assessments.MX + MN was superior to MX alone in terms of hair count, hair thickness and investigator assessment. MN at a depth of 0.6 mm showed trends of better efficacy compared to 1.2 mm.Microneedling combined with minoxidil was effective in treating AGA, with the 0.6 mm microneedling depth showing potential advantages. The treatment was safe and well-tolerated.Small sample size, variations in baseline hair counts and thickness.More pain reported in Group 2 (1.2 mm needles) than in Group 3 (0.6 mm).
    2
    Yu et al (2018)n=19 (M).iconAGASplit scalp study.5% MX and fractional radiofrequency MN.Side 1: 5% MX
    Side 2: 5% MX + fractional radiofrequency MN.    		Side 2: 1.5 mm needles.Once every 4 weeks.20 weeks.Hair counts, hair diameters, photographic evaluation, self assessment.Hair counts and diameters increased on both sides of the scalp, however, the changes to hair counts and diameters were greater on side 2 vs. side 1.5% minoxidil + fractional radiofrequency MN appears to be an effective and safe treatment option for AGA.Small sample size, short-term study.No serious adverse events were reported.
    3
    Kumar et al (2018)n=68 (M). iconAGAHospital-based, prospective, single-observer blinded study.MN and MX.Group 1: MN plus 5% topical MX.
    Group 2: 5% MX alone.    		Dermaroller with a needle length of 1.5 mm used until pinpoint bleeding was observed.Group 1: twice daily application + weekly MNfor four weeks then every 2 weeks for four sessions.
    Group 2: twice daily application.    		12 weeks.Increase in hair count from baseline, and patients’ self-assessment of hair growth using a visual analog scale (VAS).Mean increase in hair count at week 12: Group 1: (12.82±6.82) Group 2: (1.89±8.94).MN + 5% MX is an effective, and promising therapy for AGA, this response were only conserved by continuous use of minoxidil.Small sample size and short follow-up period. Group 1:
    Mild pain and discomfort during the procedure.
    Group 2: No adverse effects seen.
    2
    Dhurat et al (2013)n=100 (M)
    Group 1 = 50
    Group 2 = 50    		iconAGARandomized, comparative, evaluator-blinded studyMN and 5% MX.Group 1: MN + 5% MX.
    Group 2: 5% MX.    		Dermaroller with a needle length of 1.5 mm sized needles.5% MX twice daily with MN weekly,12 weeks.

    		Change from baseline hair counts using macrophotographs, patient assessment of hair growth, investigator assessment of hair growth.Hair Count: Mean change in hair count at week 12 was significantly greater for Group 1 (91.4 hairs/cm2) compared to Group 2 (22.4 hairs/cm2).
    Investigator Assessment: 80% in Group 1 showed a response of +2 - +3 (increased/greatly increased) on the visual analog scale compared to none in Group 2.
    Patient Assessment: 82% in Group 1 reported more than 50% improvement in hair growth. 4.5% in Group 2 reported the same level of improvement.    		Combination MN with 5% MX may be more effective in promoting hair growth in men with AGA.Short duration, no control group.None mentioned.
    3
    Lee et al (2013)n=11 (F)iconFPHLSplit-scalp, single-blinded, placebo-controlled, pilot study.Growth factor solution, MN, and normal saline.Side 1: Growth factor topical application followed by MN.
    Side 2: Normal saline topical application followed by MN.    		Dermaroller with a needle depth of 0.5 mm.Once weekly.5 weeks.

    		Phototrichogram (hair count), patient satisfaction assessed through questionnaires.Increase of more than 10% in hair shaft count was observed on the treated side compared to baseline. Patient satisfaction scores were also higher for the treated side.Topical application of growth factors alongside MN can enhance hair density in women with FPHL.Small sample size, focused on a specific demographic which may limit the generalizability of the findings.No adverse events recorded.
    2
    Yoo et al (2010)n=8
    F = 6,
    M = 2

    iconAT
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    6
    iconAU
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    2
    		Pilot, split scalp, comparative study.
    		Photodynamic therapy (PDT), MN, 5-aminolevulinate (MAL).Side 1: PDT with MAL and MN.
    Side 2: PDT with MAL.    		Dermaroller with a needle depth of 0.5 mm.Every 4 weeks.12 weeks with a final evaluation at 16 weeks.Photographs taken before each session and 1 month after the final treatment. Dermatologists assessed treatment responses by comparing photographs. Hisstologic changes assessed through biopsies.None of the patients achieved hair regrowth in either the microneedled or non-microneedled areas. Histologic analysis showed no difference in hair follicle density between the microneedled and control areas.PDT with MAL might not be effective for recalcitrant alopecia totalis regardless of MN treatment. Small sample size.Mild pain and erythema which resolved after several days. No serious events reported.
    1