Dose-response study of topical minoxidil in male pattern baldness

Compliance to Topical Minoxidil and Reasons for Discontinuation among Patients with Androgenetic Alopecia

INTRODUCTION

This study assessed the levels of compliance to topical minoxidil (TM) among male and female patients with androgenetic alopecia (AGA) and analyzed the factors associated with minoxidil discontinuation.

METHOD

A retrospective study was conducted among 400 consecutive patients with AGA who presented to a dermatology clinic and who were prescribed minoxidil 2% or 5% in the past 5 years. Demographic factors, other previous treatments, and minoxidil parameters including the dose (2% or 5%), total duration of use, treatment results, and side effects were collected.

RESULT

The mean age of the patients was 32.41 years [standard deviation (SD) 8.18], and 66.5% were female. The majority of patients (82.5%) did not receive any previous treatment for AGA. Of the total patients, 345 (86.3%) have discontinued minoxidil. Discontinuation rate showed no association with sex (p = 0.271), age category (p = 0.069), or previous treatment (p = 0.530). Furthermore, the likelihood of minoxidil discontinuation decreased with the increase in treatment duration (p < 0.001) and was significantly lower among patients who reported improvement (69.3%) or stabilization of hair shedding (64.1%) compared with those who reported baby hair (88.9%) or no efficacy (95.3%) (p < 0.001). Furthermore, having experienced an adverse effect of minoxidil was associated with 93.6% discontinuation rate compared with 75.8% in the case of no side effects (p < 0.001). Adjusted analysis showed that minoxidil discontinuation was independently association with longer duration of use [> 1 year; odds ratio (OR) 0.22; p < 0.001], perceived improvement (OR 0.17; p < 0.001) or stabilization (OR 0.14; p < 0.001), and the occurrence of side effects (OR 3.06; p = 0.002).

CONCLUSIONS

The clinical use of TM in AGA is limited by a substantially low compliance even in absence of adverse effects. We emphasize the importance of educating patients regarding the treatment's side effects and the need to use minoxidil for a minimum of 12 months to assess treatment efficacy.

Relative Efficacy of Minoxidil and the 5-α Reductase Inhibitors in Androgenetic Alopecia Treatment of Male Patients: A Network Meta-analysis

IMPORTANCE

There are knowledge gaps regarding the relative efficacy of 3 commonly used drugs for androgenetic alopecia (AGA), namely, minoxidil and the two 5-α reductase inhibitors dutasteride and finasteride.

OBJECTIVE

To examine the relative efficacy of any dose and administration route of minoxidil, dutasteride, and finasteride for the treatment of male AGA.

DATA SOURCES

Systematic searches were performed in PubMed on March 5, 2021, without date restrictions.

STUDY SELECTION

Eligible studies included those that investigated monotherapy with any dose and administration route of minoxidil, dutasteride, and finasteride.

DATA EXTRACTION AND SYNTHESIS

Data on the mean (SD) difference and sample size were used for the bayesian network meta-analyses. League tables and surface under the cumulative ranking curve values were used to examine the relative efficacy of the interventions.

MAIN OUTCOMES AND MEASURES

Study end points were change in total and terminal hair count after 24 and 48 weeks of therapy. The 4 end points were quantified in hairs per square centimeters.

RESULTS

The PubMed search yielded 848 records; after the 2 stages of screening, 23 studies were eligible for quantitative analyses. Mean (SD) age of patients ranged from 22.8 (3.3) years to 41.8 (12.3) years. The greatest increase in total hair count at 24 weeks (ie, first end point) was with 0.5 mg/d of dutasteride, which was significantly more efficacious than 1 mg/d of finasteride (mean difference, 7.1 hairs/cm2; 95% CI, 5.1-9.3 hairs/cm2) and minoxidil (0.25 mg/d [mean difference, 23.7 hairs/cm2; 95% CI, 9.5-38.0 hairs/cm2], 5 mg/d [mean difference, 15.0 hairs/cm2; 95% CI, 3.9-26.1 hairs/cm2], and 2% solution [mean difference, 8.5 hairs/cm2; 95% CI, 4.8-12.3 hairs/cm2]). The greatest increase in terminal hair count at 24 weeks (ie, second end point) was with 5 mg/d of minoxidil, which was significantly more efficacious than the 0.25-mg/d dose (mean difference, 43.6 hairs/cm2; 95% CI, 29.7-57.7 hairs/cm2) and its topical forms (in 2% [mean difference, 29.3 hairs/cm2; 95% CI, 21.1-37.5 hairs/cm2] and 5% [mean difference, 29.8 hairs/cm2; 95% CI, 19.7-39.8 hairs/cm2]); 5 mg/d of minoxidil was significantly more efficacious than 1 mg/d of finasteride (mean difference, 10.4 hairs/cm2; 95% CI, 2.2-18.6 hairs/cm2). The greatest increase in total hair count at 48 weeks (ie, third end point) was with 5 mg/d of finasteride, which was significantly more efficacious than 2% topical minoxidil (mean difference, 20.7 hairs/cm2; 95% CI, 9.5-31.9 hairs/cm2). The greatest increase in terminal hair count at 48 weeks (ie, fourth end point) was with 1 mg/d of finasteride, which was significantly more effective than topical minoxidil (in 2% [mean difference, 32.1 hairs/cm2; 95% CI, 23.9-40.3 hairs/cm2] and 5% [mean difference, 26.2 hairs/cm2; 95% CI, 16.2-36.2 hairs/cm2]).

CONCLUSIONS AND RELEVANCE

As efficacy data from head-to-head trials accumulate, there could be a better sense of the relative efficacy of the different doses of the 5-α reductase inhibitors and minoxidil. The findings of this meta-analysis contribute to the comparative effectiveness literature for AGA therapies with regard to the compared interventions.

Short-Term Efficacy of Autologous Cellular Micrografts in Male and Female Androgenetic Alopecia: A Retrospective Cohort Study

Purpose

Autologous cellular micrografts (ACM) is a novel treatment method in hair loss, and few data are available regarding its efficacy. The present study was carried out to assess the short-term clinical efficacy of a single application of ACM in the treatment of male and female androgenetic alopecia (AGA).

Materials and Methods

This was a single-center retrospective study involving 140 consecutive adults with confirmed AGA, who received a single session of ACM (Regenera Activa®). Efficacy was evaluated 1–6 months after treatment, by analyzing the change of trichometry parameters, which were assessed using TrichoScan digital image analysis.

Results

Depending on the scalp region, there was increase in mean hair density by 4.5–7.12 hair/cm², average hair thickness by 0.96–1.88 μm, % thick hair by 1.74–3.26%, and mean number of follicular units by 1.30–2.77, resulting in an increase of cumulative hair thickness by 0.48–0.56 unit. Additionally, the frontal region showed a significant decrease in % thin hair (−1.81%, p = 0.037) and yellow dots (−1.93 N/cm², p = 0.003). A favorable response was observed in 66.4% of the participants in the frontal region. Further, a gender-specific effect of treatment was observed.

Conclusion

ACM is a promising treatment in AGA with a short-term favorable response observed in up to approximately two-thirds of patients.

Minoxidil: a comprehensive review

Topical minoxidil (5% foam, 5% solution, and 2% solution) is FDA-approved for androgenetic alopecia (AGA) in men and women.Mechanism of action: Minoxidil acts through multiple pathways (vasodilator, anti-inflammatory agent, inducer of the Wnt/β-catenin signaling pathway, an antiandrogen), and may also affect the length of the anagen and telogen phases.Pharmacokinetics: Approximately 1.4% of topical minoxidil is absorbed through the skin. Minoxidil is a prodrug that is metabolized by follicular sulfotransferase to minoxidil sulfate (active form). Those with higher sulfotransferase activity may respond better than patients with lower sulfotransferase activity.Clinical efficacy (topical minoxidil): In a five-year study, 2% minoxidil exhibited peak hair growth in males at year one with a decline in subsequent years. Topical minoxidil causes hair regrowth in both frontotemporal and vertex areas. The 5% solution and foam were not significantly different in efficacy from the 2% solution.Oral and Sublingual minoxidil (not FDA approved; off-label): After 6 months of administration, minoxidil 5 mg/day was significantly more effective than topical 5% and 2% in male AGA. Low-dose 0.5-5 mg/day may also be safe and effective for female pattern hair loss and chronic telogen effluvium. Sublingual minoxidil may be safe and effective in male and female pattern hair loss.

Safety of low-dose oral minoxidil for hair loss: A multicenter study of 1404 patients

BACKGROUND

The major concern regarding the use of low-dose oral minoxidil (LDOM) for the treatment of hair loss is the potential risk of systemic adverse effects.

OBJECTIVE

To describe the safety of LDOM for the treatment of hair loss in a large cohort of patients.

METHODS

Retrospective multicenter study of patients treated with LDOM for at least 3 months for any type of alopecia.

RESULTS

A total of 1404 patients (943 women [67.2%] and 461 men [32.8%]) with a mean age of 43 years (range 8-86) were included. The dose of LDOM was titrated in 1065 patients, allowing the analysis of 2469 different cases. The most frequent adverse effect was hypertrichosis (15.1%), which led to treatment withdrawal in 14 patients (0.5%). Systemic adverse effects included lightheadedness (1.7%), fluid retention (1.3%), tachycardia (0.9%), headache (0.4%), periorbital edema (0.3%), and insomnia (0.2%), leading to drug discontinuation in 29 patients (1.2%). No life-threatening adverse effects were observed.

LIMITATIONS

Retrospective design and lack of a control group.

CONCLUSION

LDOM has a good safety profile as a treatment for hair loss. Systemic adverse effects were infrequent and only 1.7% of patients discontinued treatment owing to adverse effects.

Oral minoxidil treatment for hair loss: A review of efficacy and safety

BACKGROUND

Although topical minoxidil is an effective treatment option for hair loss, many patients are poorly compliant because of the necessity to apply the medication twice a day, undesirable hair texture, and scalp irritation.

OBJECTIVE

In recent years, oral minoxidil at low dose has been proposed as a safe alternative. This study reviewed articles in which oral minoxidil was used to treat hair loss to determine its efficacy and safety as an alternative to topical minoxidil.

METHODS

PubMed searches were performed to identify articles discussing oral minoxidil as the primary form of treatment for hair loss published up to April 2020.

RESULTS

A total of 17 studies with 634 patients were found discussing the use of oral minoxidil as the primary treatment modality for hair loss. Androgenetic alopecia was the most studied condition, but other conditions included telogen effluvium, lichen planopilaris, loose anagen hair syndrome, monilethrix, alopecia areata, and permanent chemotherapy-induced alopecia.

LIMITATIONS

Larger randomized studies comparing the efficacy/safety of different doses with standardized objective measurements will be needed to clarify the best treatment protocol.

CONCLUSION

Oral minoxidil was found to be an effective and well-tolerated treatment alternative for healthy patients having difficulty with topical formulations.

Electrochemical Detector for Liquid Chromatography: Determining Minoxidil in Hair-Growth Pharmaceuticals

Background:

The electrochemical behavior of minoxidil on gold (Au), Glassy Carbon (GCEs), and Carbon Paste Electrodes (CPEs) was investigated in an aqueous supporting electrolyte (phosphate buffer [pH 2.0-6.5], acetate buffer [pH 4.3], and Britton and Robinson buffer [pH 2.0-7.4]).

Methods:

For cyclic voltammetric measurements with suitable methodical parameters, CPEs catalyze electrooxidation of minoxidil more efficiently than do other electrodes. Minoxidil was detected using high-performance liquid chromatography with an electrochemical (carbon paste) detector (HPLCECD). For direct current mode, with the current at a constant potential, and measurements with suitable experimental parameters, a linear concentration from 0.02 to 2.6 mg L-1 was found. The detection limit was approximately 20 ng m L-1.

Results:

The developed method detected minoxidil samples.

Conclusion:

Findings using HPLC-ECD and HPLC with an ultraviolet detector were comparable.

Efficacy of non-surgical treatments for androgenetic alopecia: a systematic review and network meta-analysis

Androgenetic alopecia, or male/female pattern baldness, is the most common type of progressive hair loss disorder. The aim of this study was to review recent advances in non-surgical treatments for androgenetic alopecia and identify the most effective treatments. A network meta-analysis (NMA) was conducted of the available literature of the six most common non-surgical treatment options for treating androgenetic alopecia in both men and women; dutasteride 0.5 mg, finasteride 1 mg, low-level laser therapy (LLLT), minoxidil 2%, minoxidil 5% and platelet-rich plasma (PRP). Seventy-eight studies met the inclusion criteria, and 22 studies had the data necessary for a network meta-analysis. Relative effects show LLLT as the superior treatment. Relative effects show PRP, finasteride 1 mg (male), finasteride 1 mg (female), minoxidil 5%, minoxidil 2% and dutasteride (male) are approximately equivalent in mean change hair count following treatment. Minoxidil 5% and minoxidil 2% reported the most drug-related adverse events (n = 45 and n = 23, respectively). The quality of evidence of minoxidil 2% vs. minoxidil 5% was high; minoxidil 5% vs. placebo was moderate; dutasteride (male) vs. placebo, finasteride (female) vs. placebo, minoxidil 2% vs. placebo and minoxidil 5% vs. LLLT was low; and finasteride (male) vs. placebo, LLLT vs. sham, PRP vs. placebo and finasteride vs. minoxidil 2% was very low. Results of this NMA indicate the emergence of novel, non-hormonal therapies as effective treatments for hair loss; however, the quality of evidence is generally low. High-quality randomized controlled trials and head-to-head trials are required to support these findings and aid in the development of more standardized protocols, particularly for PRP. Regardless, this analysis may aid physicians in clinical decision-making and highlight the variety of non-surgical hair restoration options for patients.

Systematic review of low-level laser therapy for adult androgenic alopecia

Alopecia is a common disorder affecting over half of the world's population. Within this condition, androgenic alopecia (AA) is the most common type, affecting 50% of males over 40 and 75% of females over 65. Anecdotal paradoxical hypertrichosis noted during laser epilation has generated interest in the possibility of using laser to stimulate hair growth. In this study, we aimed to critically appraise the application of low-level laser therapy for the treatment of AA in adults. A systematic review was performed on studies identified on Medline, EMBASE, Cochrane database, and clinicaltrials.org. Double-blinded randomized controlled trials were selected and analyzed quantitatively (meta-analysis) and qualitatively (quality of evidence, risk of bias). Low-level laser therapy appears to be a promising noninvasive treatment for AA in adults that is safe for self-administration in the home setting. Although shown to effectively stimulate hair growth when compared to sham devices, these results must be interpreted with caution. Further studies with larger samples, longer follow-up, and independent funding sources are necessary to determine the clinical effectiveness of this novel therapy.

Evidence-based (S3) guideline for the treatment of androgenetic alopecia in women and in men - short version

Androgenetic alopecia is the most common hair loss disorder, affecting both men and women. Initial signs of androgenetic alopecia usually develop during teenage years leading to progressive hair loss with a pattern distribution. Moreover, its frequency increases with age and affects up to 80% Caucasian men and 42% of women. Patients afflicted with androgenetic alopecia may undergo significant impairment of quality of life. The European Dermatology Forum (EDF) initiated a project to develop evidence-based guidelines for the treatment of androgenetic alopecia. Based on a systematic literature research the efficacy of the currently available therapeutic options was assessed and therapeutic recommendations were passed in a consensus conference. The purpose of the guideline is to provide dermatologists with an evidence-based tool for choosing an efficacious and safe therapy for patients with androgenetic alopecia.

Evidence-based (S3) guideline for the treatment of androgenetic alopecia in women and in men

Androgenetic alopecia is the most common hair loss disorder, affecting both men and women. Initial signs of androgenetic alopecia usually develop during teenage years leading to progressive hair loss with a pattern distribution. Moreover, its frequency increases with age and affects up to 80 % Caucasian men and 42 % of women. Patients diagnosed with androgenetic alopecia may undergo significant impairment of quality of life. Despite the high prevalence and the variety of therapeutic options available, there have been no national or international evidence-based guidelines for the treatment of androgenetic alopecia in men and women so far. Therefore, the European Dermatology Forum (EDF) initiated a project to develop an evidence-based S3 guideline for the treatment of andro-genetic alopecia. Based on a systematic literature research the efficacy of the currently available therapeutic options was assessed and therapeutic recommendations were passed in a consensus conference. The purpose of the guideline is to provide dermatologists as well as general practitioners with an evidence-based tool for choosing an efficacious and safe therapy for patients with androgenetic alopecia.

Medical treatments for male and female pattern hair loss

Male and female pattern hair loss affects a large percentage of the population, and patients frequently present for treatment of this to their dermatologist. Here we review the many treatments available for hair loss. We review the evidence for each, and outline the most effective treatment strategies for both men and women.

LEARNING OBJECTIVE

At the conclusion of this article, the reader should be able to describe the most effective treatments for hair loss, understand their mechanism(s) of action, and explain which treatments are the best in different settings.

[Androgenetic alopecia]

Androgenetic alopecia is the most common form of hair loss in men and women. Although the clinical manifestations are different in men and women, the pathogenetic pathways leading to this type of hair loss are similar in both sexes. In short genetically predestined hair follicles show an increased sensitivity to androgens. In recent years, much new data concerning the pathophysiology, management and therapy of androgenetic alopecia has been gathered. This article gives a critical overview of these new findings and assesses their practical relevance.

Hair loss and hirsutism in the elderly

This article contains a brief review of hair follicle biology, followed by a presentation of the workup of elderly patients who present with hair loss or hirsutism. Common hair disorders, such as graying, telogen effluvium, androgenic alopecia, senescent alopecia, alopecia arcuata, hirsutism, and hypertrichosis, are discussed.

Acquired scalp alopecia. Part II: A review

The neutrophil-associated and infiltrative scarring alopecias are reviewed including folliculitis decalvans, tufted folliculitis, dissecting cellulitis of the scalp, acne keloidalis and follicular degeneration syndrome. The management of acquired scalp alopecia is also reviewed including newer, promising therapies. More specific agents targeting components of the androgen system will make the treatment of androgenetic alopecia more rewarding. Similarly new immunomodulatory therapies show great promise for the lymphocyte-associated alopecias and include a new generation of macrolide immunosuppressives (tacrolimus, SDZ ASM 981, and SDZ 281-240), some of which appear to have good transcutaneous absorption.

Hair regrowth. Therapeutic agents

Today there are new classes of hair growth promotors with proven efficacy. This article reviews the current state of the art agents for treatment of two of the most common forms of hair loss encountered in clinical practice, androgenetic alopecia and alopecia areata. Current therapeutic strategies are based on recent advances in the understanding of disordered hair growth. Practical treatment protocols are presented.

Minoxidil sulphation in human liver and platelets. A study of interindividual variability

Minoxidil requires to be sulphated to exert its hypotensive effect. We report on interindividual variability in the rate of minoxidil sulphation in 118 specimens of human liver and in platelets obtained from 100 healthy subjects and 100 newborns. The frequency distribution histogram of the hepatic activity of minoxidil sulphotransferase was positively skewed; the mean was 631 pmol.min-1 x mg-1. After logarithmic transformation of the enzyme activity, the frequency distribution histogram became symmetrical and did not significantly deviate from normality. The rate of minoxidil sulphation was not different in platelets from adults (0.74 pmol.min-1 x mg-1) and newborns (1.16 pmol.min-1 x mg-1). The frequency distribution histograms were positively skewed and the results of normal equivalent deviation analysis was compatible with the presence of at least two subgroups of sulphotransferase in liver and platelets. Thus, two phenotypes of sulphotransferase exist in human liver and platelets, and the "extensive sulphator" phenotype contributes to skewing the frequency distribution. In platelets, the percentage of subjects that fall in the two subgroups is different at birth and in adulthood. This can explain the different shape of the frequency distribution in newborn and adult platelets and suggests that platelet minoxidil sulphotransferase undergoes modification after birth.

Collagen telopeptides (cross-linking sites) play a role in collagen gel lattice contraction

Solubilized interstitial collagens will form a fibrillar, gel-like lattice when brought to physiologic conditions. In the presence of human dermal fibroblasts the collagen lattice will contract. The rate of contraction can be determined by computer-assisted planemetry. The mechanisms involved in contraction are as yet unknown. Using this system it was found that the rate of contraction was markedly decreased when collagen lacking telopeptides was substituted for native collagen. Histidinohydroxylysinonorleucine (HHL) is a major stable trifunctional collagen cross-link in mature skin that involves a carboxyl terminal, telopeptide site 16c, the sixteenth amino acid residue from the carboxy terminal of the telopeptide region of alpha 1 (I) in type I collagen. Little, if any, HHL was present in native, purified, reconstituted, soluble collagen fibrils from 1% acetic acid-extracted 2-year-old bovine skin. In contrast, HHL cross-links were present (0.22 moles of cross-link per mole of collagen) in lattices of the same collagen contracted by fibroblasts. However, rat tail tendon does not contain HHL cross-links, and collagen lattices made of rat tail tendon collagen are capable of contraction. This suggests that telopeptide sites, and not mature HHL cross-links per se, are essential for fibroblasts to contract collagen lattices. Beta-aminopropionitrile fumarate (BAPN), a potent lathyrogen that perturbs collagen cross-linking by inhibition of lysyl oxidase, also inhibited the rate of lattice cell contraction in lattices composed of native collagen. However, the concentrations of BAPN that were necessary to inhibit the contraction of collagen lattices also inhibited fibroblast growth suggestive of cellular toxicity. In accordance with other studies, we found no inhibition of the rate of lattice contraction when fibronectin-depleted serum was used. Electron microscopy of contracted gels revealed typical collagen fibers with a characteristic axial periodicity. The data provide evidence that collagen telopeptide sites play a role in collagen gel lattice contraction.

Localization of minoxidil sulfotransferase in rat liver and the outer root sheath of anagen pelage and vibrissa follicles

The precise biochemical mechanism and site(s) of action by which minoxidil stimulates hair growth are not yet clear. Minoxidil sulfate is the active metabolite of minoxidil, with regard to smooth muscle vasodilation and hair growth. Formation of minoxidil sulfate is catalyzed by specific PAPS-dependent sulfotransferase(s) and minoxidil-sulfating activities have been previously reported to be present in liver and hair follicles. One of these minoxidil-sulfating enzymes has been purified from rat liver (rat minoxidil sulfotransferase, MST) and a rabbit anti-MST antibody has been prepared. Using this anti-MST antibody, we have immunohistochemically localized minoxidil sulfotransferase in the liver and anagen hair follicles from rat. In rat pelage and vibrissa follicles, this enzyme is localized within the cytoplasm of epithelial cells in the lower outer root sheath. Although the immunolocalization of MST might not necessarily correlate with the MST activity known to be present in anagen follicles, the results of this study strongly suggest that the lower outer root sheath of the hair follicle may serve as a site for the sulfation of topically applied minoxidil.

Transdermal viprostol in the treatment of male pattern baldness

Fifty-seven men were randomly assigned for treatment of androgenetic alopecia with viprostol, vehicle, or placebo twice daily for 24 weeks. Nonvellus hair growth was assessed subjectively by both patient and investigator and objectively through hair counts from macrophotographs of the target area. Nonvellus target area hair counts declined in all three treatment groups at the end of the 6-month study. Viprostol is not an effective hair growth promoter in androgenetic alopecia.

Five-year follow-up of men with androgenetic alopecia treated with topical minoxidil

Thirty-one men with androgenetic alopecia completed 4 1/2 to 5 years of therapy with 2% and 3% topical minoxidil. Hair regrowth with topical minoxidil tended to peak at 1 year with a slow decline in regrowth over subsequent years. However, at 4 1/2 to 5 years, maintenance of nonvellus hairs beyond that seen at baseline was still evident. Topical minoxidil appears to be effective in helping to maintain nonvellus hair growth in men with androgenetic alopecia.

Australian trial of topical minoxidil and placebo in early male pattern baldness

One hundred and sixty nine men with early male pattern baldness (androgenic alopecia) were treated in a random, double-blind fashion with either 2% minoxidil solution or placebo vehicle for 24 weeks, one ml applied twice daily. After 24 weeks all patients received the active solution until week 48. After 24 weeks the minoxidil treated patients had increased their non-vellus hair counts significantly more than the placebo treated group; means were 37.6 and 8.8 hairs per reference area, 95% C.I. for difference = 10.85 to 60.75. The rate of non-vellus hair regrowth was also greater among minoxidil treated patients than placebo treated patients. Nine (12.5%) evaluable minoxidil treated patients compared with 2 (2.7%) evaluable placebo treated patients reported moderate or dense hair regrowth at week 24. Minimal regrowth was reported by 18 (25%) active group and 15 (20%) placebo group patients. The investigators considered that 3 (2%) of the minoxidil group and none of the placebo group had moderate hair regrowth and that none had dense regrowth. After 48 weeks treatment 28 (23%) patients considered that they had moderate hair regrowth and the investigators considered that 14 (12%) patients had moderate regrowth. None had dense growth. No serious adverse reactions or deaths were reported. Minoxidil solution appeared to be an efficacious and safe treatment for early androgenic alopecia.

Natural history of androgenetic alopecia

Twenty-two men with patterns III-Va androgenetic alopecia were entered into a 10-month study aimed at establishing information on the natural progression of hair loss over a period of time typical of studies of hair growth promoters. The methodology employed was the same as that in published clinical trials of topical minoxidil, but the men refrained from application of either active drug or vehicle to their scalps. As one of the potential explanations for the observed 'placebo-effect' seen in non-vellus hair counts in the topical minoxidil trials was a learning curve of novice hair counters, we were particularly interested in evaluating this in our 'no-treatment' trial. To that end, both a novice (Observer I) and an experienced (Observer II) hair counter independently performed the hair counts. There was a mean decline in the number of vertex target area non-vellus hairs (-17.2 +/- 80.3 for Observer I and -26.6 +/- 63.5 for Observer II) at the end of 10 months; this was not significant. The novice's hair counts were lower than the experienced observer's counts at baseline, and the difference remained relatively constant during the study. Without the application of a placebo, there was no increase in hair growth, making it unlikely that the methods of hair counting led to the 'placebo-effect' seen in prior topical minoxidil studies.

Topical minoxidil: cardiac effects in bald man

Systemic cardiovascular effects during chronic treatment with topical minoxidil vs placebo were evaluated using a double-blind, randomized design for two parallel groups (n = 20 for minoxidil, n = 15 for placebo). During 6 months of follow-up, blood pressure did not change, whereas minoxidil increased heart rate by 3-5 beats min-1. Compared with placebo, topical minoxidil caused significant increases in LV end-diastolic volume, in cardiac output (by 0.751 min-1) and in LV mass (by 5 g m-2). We conclude that in healthy subjects short-term use of topical minoxidil is likely not to be detrimental. However, safety needs to be established regarding ischaemic symptoms in patients with coronary artery disease as well as for the possible development of LV hypertrophy in healthy subjects during years of therapy.

Comparable efficacy of 2% minoxidil gel and solution formulations in the treatment of male pattern alopecia

Sixty-four healthy men with early male pattern baldness completed a 6-month, double-blind, placebo-controlled study in which the efficacy of 2% minoxidil gel and solution formulations was compared. Treatment with topical 2% minoxidil in both formulations resulted in a statistically significant increase in terminal hair growth referenced against baseline counts. The patients' subjective assessments of hair growth did not correlate well with actual increase in terminal hair counts.

Topical minoxidil in the treatment of male pattern alopecia

Male pattern hair loss (androgenetic alopecia) is a common problem. In fact, it affects nearly all males to some degree. Expression of the disorder is variable, and while it is never life-threatening, it often becomes a major source of consternation. The biology of the process is poorly understood, and no current therapy can halt or reverse the process. Only cosmetic surgery, which is painful, time consuming, and expensive, has been effective. In the past 7 years, since it was noted that a patient taking minoxidil for hypertension had reversal of male pattern hair loss, awareness of a possible therapeutic role for topical minoxidil in the management of this disorder has grown among physicians, scientists, and the general public. It can be concluded from available data that topical application of minoxidil is effective in providing cosmetically satisfying thickening of hair in a select group of individuals with male pattern hair loss. The drug's mechanism of action remains obscure. No serious side effects have been demonstrated with its use, however, and it is therefore advised in selected patients.

Topical minoxidil in male pattern baldness: effects of discontinuation of treatment

Ten men with male pattern baldness who had been treated with 2% or 3% minoxidil for at least 4 months were evaluated for any changes in scalp hair growth on and off drug. Objective assessments by hair counts showed a mean doubling of nonvellus target scalp hairs on topical minoxidil and loss of most of these recruited hairs when the drug was discontinued. Four of ten men had nonvellus hair counts off topical minoxidil that fell below baseline levels. Thus, hair growth on topical minoxidil is not sustained when the drug is discontinued.

Dermatologic therapy: December 1985 to December 1986

I have reviewed the significant therapeutic changes reported in the English literature between December 1985 and December 1986. Readers should review the original articles in toto before attempting any new experimental or controversial therapy summarized.

Effect of ultraviolet light on topical minoxidil-induced hair growth in advanced male pattern baldness

Nine healthy men with type IVa or Va male pattern baldness completed a 4-month single-blinded controlled pilot study designed to assess the effect of ultraviolet light (UVL) on topical minoxidil-induced hair growth. Subjects applied 2% topical minoxidil solution twice daily to their balding scalps and to one target area on the upper arm. These men, all of whom had either skin type II or III, were randomized to also receive either incremental doses of UVB or PUVA (topical psoralen) twice weekly to one side of their scalp and to a 2.5 cm target area on the nonminoxidil-treated upper ipsilateral arm. Vellus, nonvellus, and total hair counts were done in two 1-inch in diameter circular target areas in symmetric regions of the scalp and on each upper arm at regular intervals. All nine subjects had an increase in target nonvellus hair and a net loss of vellus hair in scalp target area treated with topical minoxidil. Concomitant UVL did not have a significant synergistic nor adverse effect on topical minoxidil-induced hair growth.

Topical minoxidil. A preliminary review of its pharmacodynamic properties and therapeutic efficacy in alopecia areata and alopecia androgenetica

When minoxidil is administered orally for periods in excess of 1 month, hypertrichosis occurs as a side effect in a majority of patients. Consequently, topical minoxidil has been developed to try to improve hair growth in patients with alopecia areata and alopecia androgenetica. Preliminary studies have shown that topical minoxidil promotes cosmetically acceptable hair regrowth in a variable proportion of patients with alopecia areata. Data from a large multicentre trial indicate that cosmetically worthwhile results are achieved in about one-third of subjects with alopecia androgenetica after 1 year of treatment. A much higher proportion (about 80%) of patients with alopecia androgenetica exhibited some non-vellus hair regrowth after 1 year, and whether more of these patients would develop a cosmetically acceptable result with a longer treatment period is an important area of future investigation. Initial indications suggest that less severe disease is a predictor of likely response. Thus, topical minoxidil would seem to be a useful treatment modality for patients with alopecia androgenetica--a disease for which no other safe and effective drug therapy exists. Results from treating patients with alopecia areata with topical minoxidil, although encouraging, have been more variable and require further evaluation. Even though a number of questions remain to be answered about topical minoxidil (as would be expected at this stage in its development), it would seem to be the first available drug with the potential to promote substantial hair regrowth in these divergent diseases.