That’s a possibility in the future according to this recent study.  It appears researchers in China are testing whether it’s possible to create a time-release form of finasteride, the active ingredient in Propecia.

The idea behind time-release medication is that it’s encapsulated in such a way that the drug releases into the body in a controlled fashion over an extended period of time, thereby eliminating the need to take a tablet every day.

In this test the finasteride was encapsulated in a propylene carbonate maleate plastic.    When placed into a lab testing solution, the drug was found to release continuously for a period of 5-6 weeks.

This is just an early test, but since there are already time-release drugs for birth control, it’s quite possible that in the future this type of drug delivery method will be available to users of Propecia.
 

Preparation of novel polymeric microspheres for controlled release of finasteride.

Int J Pharm. 2007 May 13.
Peng D, Huang K, Liu Y, Liu S.
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.

The utility of the novel polycarbonate, poly(propylene carbonate maleate) (PPCM) to encapsulate and control the release of finasteride, via microspheres, was investigated. The PPCM microspheres loaded with finasteride were elaborated by a simple oil-in-water (O/W) emulsion-solvent evaporation method. Various manufacturing parameters, including the concentration of polymer in dichloromethane (DCM) and the polymer:finasteride ratios were altered to optimize process variables during the microspheres production. The effects of these changes on the characteristics of the microspheres were examined. The structure and morphology were characterized by wide-angle X-ray diffraction (WXRD) and scanning electron microscopy (SEM). The results showed that the mean diameter of microspheres was approximately 2mum, and had both smooth and spherical surfaces. Greater encapsulation efficiency was obtained by increasing the ratios of polymer:finasteride and the concentration of PPCM in DCM. In vitro drug release of these microcapsules was performed in a pH 7.4 phosphate-buffered solution. The release profiles of finasteride from PPCM microcapsules were found to be biphasic with a burst release followed by a gradual release phase. A prolonged in vitro drug release profile was observed. After an initial burst, a continuous drug release was observed for up to 5-6 weeks.
 

PMID: 17580108 

In this medical report a 4 year-old girl was examined by doctors after suffering from hair loss for several weeks.

The medical examination appeared to show that she was healthy and had no apparent symptoms of any medical problems and she was not taking medications.   She however did drink a lot of cow’s milk.

Numerous tests were conducted including blood tests.  Everything appeared to be normal except that her zinc levels were low.  The doctors told her parents to give her a 50 mg zinc supplement daily for 6 months.

Within 3 weeks of taking it her hair loss stopped and by 4 months she showed no signs of any hair loss.

Zinc can be depleted by high stress levels and can cause hair loss as in this case. In order to get sufficient zinc in your diet some good sources are wheat germ, brewer’s yeast, pumpkin seeds, oysters, shrimps and egg yolks.  Otherwise zinc supplements are readily available.

The US recommended daily amount (RDA) of zinc is 15 mg.  Don’t overdo it because if you take too much zinc it’s also bad for you and can cause hair loss too.  The key is to take just the right amount.

While cases like this are unusual, there are some dietary deficiencies that can cause hair loss.   This is why it’s important for people to seek a medical diagnosis for their hair loss rather than self-diagnosing themselves.

Diffuse alopecia in a child due to dietary zinc deficiency.

Skinmed. 2007 Jul-Aug;6(4):199-200.
Alhaj E, Alhaj N, Alhaj NE.

A 4-year-old girl was evaluated for hair loss of a few weeks’ duration. History of the present illness, medical history, and review of systems were obtained from the parents, who described progressive diffuse hair loss with hair dryness and brittleness, with no change in the child’s eating habits or any other unusual symptoms. No fever, weight loss, diarrhea, vomiting, abdominal pain, chronic cough, dyspnea, change in appetite, change in bowel habit, or urinary symptoms were noted. On further questioning, her nutritional history revealed that she always favored cow’s milk in her diet. The patient has been healthy with no significant medical history, surgical history, psychiatric history, or history of hospitalization. She was taking no medications. Her mother’s pregnancy and the child’s birth history were uneventful. The child was up-to-date on her vaccinations. Her physical examination showed a healthy-appearing child who was at 50% on the height chart and 70% on the weight growth chart.

She was afebrile with a respiratory rate of 24 breaths per minute, pulse rate of 110 beats per minute, and pulse oximetry of 99% on room air. Skin examination revealed interstitial diffuse patchy alopecia with very dry hair and nonscarred, normal-appearing scalp. The hair pull test was normal, with 4 hairs extracted. Results of examination of her eyes (including visual acuity) and lungs were normal, and no abnormalities were found on heart, abdominal, musculoskeletal, and neurologic examinations. Laboratory workup showed normal electrolytes, blood urea nitrogen, creatinine, and blood sugar levels. Her complete blood cell count with differential was normal, ferritin concentration level was 110 ng/mL (reference, 40-200 ng/mL), iron level was 75 microg/dL (reference, 35-175 microg/dL), and total iron-binding capacity was 310 microg/dL (reference, 245-400 microg/dL). Levels of liver enzymes, total bilirubin, serum protein, and albumin were normal, as were the results of urinalysis. Thyroid function test results were normal and levels of vitamins A and D were also normal. Low levels of serum zinc were measured repeatedly at 48 and 61 microg/dL (reference, 66-144 microg/dL) at 2 different laboratories.

She was started on zinc supplement (50 mg daily) for 6 months and her diet was modified. The hair loss stopped in 3 weeks. Follow-up in 4 months showed no evidence of alopecia, with normal-looking hair.

PMID: 17618180

Researchers in Japan have found that chemical compounds found in cayenne peppers and soy beans stimulate hair growth.

Capsaicin - a chemical component in cayenne peppers – has been shown to increase IGF-I production in previous studies. Insulin-like growth factor-I (IGF-I) plays an important role in hair growth.  In another separate study isoflavone - a phytoestrogen found in soy beans - was also found to increase IGF-1 production.

In the study below the researchers decided to test a combination of capsaicin and isoflavone as a hair growth stimulant.
   
They first tested it on mice and gave the mice oral doses of capsaicin and isoflavone for a period of 4 weeks.   After the 4 weeks they found that the mice that had been given these chemical compounds had increased IGF-I levels in their dermal papillae of their hair follicles.

The researchers then gave it to human volunteers suffering with hair loss.   Volunteers with alopecia (hair loss) were given oral doses of capsaicin (6mg/day) and isoflavone (75mg/day) for 5 months.

After 5 months the plasma (blood) levels of IGF-I were significantly increased from baseline levels in the 31 volunteers who had taken the active ingredients, compared to the 17 volunteers who just got a placebo.

In addition, the number of volunteers with alopecia who showed promotion of hair growth at 5 months was significantly higher among volunteers administered capsaicin and isoflavone than the placebo group.

Based on this outcome the researchers concluded that combined administration of capsaicin and isoflavone might increase IGF-I production in hair follicles in the skin, thereby promoting hair growth.
 

Administration of capsaicin and isoflavone promotes hair growth by increasing insulin-like growth factor-I production in mice and in humans with alopecia.

Growth Horm IGF Res. 2007 Jun 12
Harada N, Okajima K, Arai M, Kurihara H, Nakagata N.
Department of Translational Medical Science Research, Nagoya City University, Graduate School of Medical Sciences, Kawasumi 1, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan.

OBJECTIVE: Insulin-like growth factor-I (IGF-I) plays an important role in hair growth. Capsaicin activates vanilloid receptor-1, thereby increasing the release of calcitonin gene-related peptide (CGRP) from sensory neurons, and CGRP has been shown to increase IGF-I production. We recently reported that isoflavone, a phytoestrogen, increases production of CGRP by increasing its transcription in sensory neurons. These observations raise the possibility that administration of capsaicin and isoflavone might promote hair growth by increasing IGF-I production. In the present study, we examined this possibility in mice and humans with alopecia.
 
DESIGN: Dermal IGF-I levels, immunohistochemical expression of IGF-I in the skin and hair regrowth were examined after capsaicin and isoflavone administration to wild-type (WT) mice and CGRP-knockout mice. Plasma levels of IGF-I and promotion of hair growth were evaluated in 48 volunteers with alopecia after administration of capsaicin and isoflavone for 5months.
 
RESULTS: Subcutaneous administration of capsaicin significantly increased dermal IGF-I levels at 30min after administration in WT mice (p<0.01), but not in CGRP-knockout mice. Dermal levels of IGF-I were significantly higher in WT mice administered capsaicin and isoflavone for 4wks than in those administered capsaicin alone for 4wks (p<0.01) and in those administered neither of them (p<0.01). Immunohistochemical expression of IGF-I at dermal papillae in hair follicles was increased in WT mice administered capsaicin and isoflavone and in those administered capsaicin alone at 4wks. Hair regrowth was clearly more accelerated in WT mice administered capsaicin and isoflavone for 4wks than in those administered capsaicin alone for 4wks and in those administered neither of them. Plasma levels of IGF-I were significantly increased from baseline levels in 31 volunteers with alopecia at 5months after oral administration of capsaicin (6mg/day) and isoflavone (75mg/day) (p<0.01), while they were not increased in 17 volunteers with alopecia administered placebo. The number of volunteers with alopecia who showed promotion of hair growth at 5months after administration was significantly higher among volunteers administered capsaicin and isoflavone (20/31: 64.5%) than among those administered placebo (2/17: 11.8%) (p<0.01).
 
CONCLUSIONS: These observations strongly suggested that combined administration of capsaicin and isoflavone might increase IGF-I production in hair follicles in the skin, thereby promoting hair growth. Such effects of capsaicin and isoflavone might be mediated by sensory neuron activation in the skin.

PMID: 17569567

Traction alopecia is a totally preventable type of hair loss that results from hair being under constant stress.

In this study conducted in South Africa, researchers wanted to see if there is a correlation between various skin disorders and hair styles in Africans.

They evaluated both boys and girls in this study which examined 1,042 school children.

The researchers found that traction alopecia (TA) was significantly more common with relaxed than natural hair.   This appears to be a result of girls who had relaxed their hair and had pulled it into ponytails which then caused the stress on the hair.

Additionally it was found that with the girls, the number affected by TA increased with age from 8.6% of girls who had TA in the first year of school, to 21.7% having it in the last year of high school.

Based on this study it’s clear that traction alopecia is a result of hair styling choices and thus TA is easily preventable by avoiding hairstyles that put the hair under stress.

Hairdressing is associated with scalp disease in African schoolchildren.

Br J Dermatol. 2007 Jun 6
Khumalo NP, Jessop S, Gumedze F, Ehrlich R.
Division of Dermatology, Groot Schuur Hospital and the University of Cape Town, Observatory 7925, South Africa.

Background: Anecdotal reports suggest that certain disorders are common in African hair and may be associated with hairstyles.

Objectives: A cross-sectional study of 1042 schoolchildren was performed to test this hypothesis.

Methods: A questionnaire was administered and scalp examinations performed, after ethics approval.

Results: Participants included 45% boys and 55% girls. The majority of boys, 72.8%, kept natural hair with frequent haircuts (within 4 weeks). The prevalence of acne (folliculitis) keloidalis nuchae (AKN) was 0.67% in the whole group and highest (4.7%) in boys in the final year of high school, all of whom had frequent haircuts. The majority of girls (78.4%) had chemically relaxed hair, which was usually combed back or tied in ponytails, vs. 8.6% of boys. Traction alopecia (TA) was significantly more common with relaxed than natural hair, with an overall prevalence of 9.4% (98 of 1042) and of 17.1% in girls, in whom it increased with age from 8.6% in the first year of school to 21.7% in the last year of high school. The proportion with TA in participants with a history of braids on natural hair was lower (22.9%), but not significantly, than among those with a history of braids on relaxed hair (32.1%). No cases of central centrifugal cicatricial alopecia were identified.

Conclusions: We found associations between hairstyle and disease in our population of schoolchildren. AKN appears to be associated with frequently cut natural hair and TA with relaxed hair. These associations need further study for purposes of disease prevention.

PMID: 17553035

Doctors in India tested a plant-based herbal hair growth solution on mice and found it to be effective.

The formula was derived from three herbs traditionally acclaimed for their hair growth-promoting potential.  The herbs are Cuscuta reflexa (Roxb.), Citrullus colocynthis (Schrad.), and Eclipta alba (Hassk.)

In the study they used several herbal formulations containing petroleum ether extracts of the three herbs in varying ratios and evaluated the formulations for their hair growth-promoting activity.

In tests done on mice the hair growth cycles were sped up and a greater number of hair follicles were in the anagen or growth phase from the use of the herbal formula, compared to the control solution.

They also tested it alongside 2% minoxidil and it appears it was comparable in terms of promoting hair growth in the mice.

The doctors concluded that the prepared formula holds the potential to be used as a hair loss treatment.   The actual formula with the percentage of each ingredient that yielded this result was not disclosed.

Development and evaluation of polyherbal formulation for hair growth-promoting activity.

J Cosmet Dermatol. 2007 Jun;6(2):108-12
Roy RK, Thakur M, Dixit VK.
Department of Pharmaceutical Sciences, Dr. H.S. Gour University, Sagar, Madhya Pradesh, India.

Background: Cuscuta reflexa (Roxb.), Citrullus colocynthis (Schrad.), and Eclipta alba (Hassk.) are traditionally acclaimed herbs for their hair growth-promoting potential.

Aim: In the present study, it was envisaged to prepare herbal formulations containing petroleum ether extracts of the three herbs in varying ratio and evaluating the formulations for the hair growth-promoting activity.

Methods: The formulations as well as minoxidil (2%) solution (positive control) were applied topically on shaved skin of rats, and the time required for initiation and completion of hair growth cycle was recorded.

Results and conclusions: Hair growth initiation time was markedly reduced to one third on treatment with the prepared formulation compared with control animals. The time required for complete hair growth was also reduced by 32%. Quantitative analysis of hair growth cycle after treatment with formulations and minoxidil (2%) exhibited greater number of hair follicles in anagenic phase compared with control.

The results thus corroborate with the traditionally acclaimed hair growth-promoting capabilities of the plants. The prepared formulation also holds potential for treatment of alopecia.

PMID: 17524127

These women had no clinical improvement from the classical treatments with antiandrogens, isotretinoids or corticosteroids.   Their hypothesis was that some of these women have an excessive activity of the enzyme 5alpha-reductase.

To test this they gave 12 patients – six of whom had acne and the other six hair loss – a daily dose of 5mg of finasteride.

The results were overwhelmingly positive, 9 of the 12 patients (75%) benefited from the treatment, their symptoms decreased significantly and they felt better psychologically than before the administration of finasteride. The other three patients did not benefit at all from finasteride and reported no change in the extent of the acne/alopecia. The treatment was generally well tolerated, and only a few adverse effects were noted.

They concluded that in these types of patients an excessive activity of the 5alpha-reductase enzyme may the root cause of acne or hair loss.   However since 25% of the patients had no change, there must also be other pathways in the development of acne and alopecia in women who have normal levels of free testosterone.

It’s important to state that women who are pregnant or may become pregnant should not be taking finasteride and neither Propecia nor Proscar has been approved for use by women in the USA.
 

Effect of finasteride 5 mg (Proscar) on acne and alopecia in female patients with normal serum levels of free testosterone.

Gynecol Endocrinol. 2007 Mar;23
Kohler C, Tschumi K, Bodmer C, Schneiter M, Birkhaeuser M.
Division of Gynaecological Endocrinology and Reproductive Medicine, Department Ob/Gyn, University of Berne. Berne. Switzerland.

Background: In some women with acne or alopecia who have normal serum levels of free testosterone, no clinical improvement can be reached by the classical treatment with antiandrogens, isotretinoids or corticosteroids. Our hypothesis is that some of these women have an excessive activity of the enzyme 5alpha-reductase.

Objective: To evaluate the subjective benefit of the treatment with finasteride (5 mg/day) in women with normal serum levels of free testosterone suffering from acne or alopecia.

Design: This was a retrospective study evaluating a questionnaire filled out by 12 patients, six of whom had acne and six of whom had alopecia.

Results: Nine of the 12 patients benefited from the treatment, their symptoms decreased significantly and they felt better psychologically than before the administration of finasteride. The other three patients did not benefit at all from finasteride and reported no change in the extent of the acne/alopecia. Treatment was generally well tolerated, only a few adverse effects were noted.

Conclusions: Nine of the 12 patients benefited from the treatment. This supports our hypothesis of an excessive activity of 5alpha-reductase enzyme in peripheral tissue in these patients. The fact that three of the patients did not realize any change in their symptom severity implies that there must also be other pathways in the genesis of acne and alopecia in women with normal levels of free testosterone. Further evaluation is needed to elucidate more precise indications for the administration of finasteride in women with acne and alopecia.
Source: PMID 17454167

Koran researchers set out to determine why this is.   They used human hair follicles that were cultured in a lab to test the growth response to minoxidil and to a combination of both minoxidil and retinoic acid.

Their tests confirmed that the combination of retinoic acid and minoxidil was more effective than minoxidil on its own.

After evaluating the various cells and growth factors before and after the solution was applied they were able to determine that the combination works in two different ways.

1. Promoting the growth of cells more effectively than minoxidil alone.
2. Prolonging the lifespan of the dermal papilla and epithelial cells by preventing premature cell death.

Promotive Effect of Minoxidil Combined with All-trans Retinoic Acid (tretinoin) on Human Hair Growth in Vitro.

J Korean Med Sci. 2007 Apr;22
Kwon OS, Pyo HK, Oh YJ, Han JH, Lee SR, Chung JH, Eun HC, Kim KH.
Department of Dermatology, Seoul National University College of Medicine, Laboratory of Cutaneous Aging and Hair Research, Clinical Research Institute, Seoul National University Hospital, Institute of Dermatological Science, Seoul National University, Seoul, Korea.

Minoxidil induces hair growth in male pattern baldness and prolongs the anagen phase. All-trans retinoic acid (ATRA) has been reported to act synergistically with minoxidil in vivo: they can enhance more dense hair regrowth than either compound alone. We evaluated the effect of minoxidil combined with ATRA on hair growth in vitro. The effect of co-treatment of minoxidil and ATRA on hair growth was studied in hair follicle organ culture.

In cultured human dermal papilla cells (DPCs) and normal human epidermal keratinocytes, the expressions of Erk, Akt, Bcl-2, Bax, P53 and P21 were evaluated by immunoblot analysis.

Minoxidil plus ATRA additively promoted hair growth in vitro, compared with minoxidil alone. In addition, minoxidil plus ATRA elevated phosphorylated Erk, phosphorylated Akt and the ratio of Bcl-2/Bax, but decreased the expressions of P53 and P21 more effectively than by minoxidil alone. Our results suggest that minoxidil plus ATRA would additively enhance hair growth by mediating dual functions:

1) the prolongation of cell survival by activating the Erk and Akt signaling pathways, and 2) the prevention of apoptosis of DPCs and epithelial cells by increasing the ratio of Bcl-2/Bax and downregulating the expressions of P53 and P21.
 

Source: PMID 17449938

Drug testing for athletes is an integral part of professional sports today.   We recently reported on an Australian soccer player who was subjected to disciplinary action because he was found to be using finasteride (Propecia).

The reason why finasteride is banned is because this hair loss drug causes changes to the person’s hormonal profile that make it difficult to detect steroid use.

A person could therefore use finasteride to mask their steroid use and thus evade detection.

This study examined the exact reason why finasteride and other 5alpha-reductase inhibitors cause problems with drug testing.

According to the study, the use of 5alpha-reductase inhibitors (finasteride or dutasteride) causes considerable problems because steroid profile parameters, which are commonly considered stable, are highly affected and complicate the detection of steroid abuse. In addition, the suppression of production and renal excretion of 5alpha-steroids such as 19-norandrosterone generated from anabolic agents such as 19-norandrostenedione may lead to false-negative doping-control results, because urine specimens are reported positive only when a threshold level of 2 ng/mL is exceeded.

Doping-control analysis of the 5alpha-reductase inhibitor finasteride: determination of its influence on urinary steroid profiles and detection of its major urinary metabolite.

Ther Drug Monit. 2007 Apr;29
Thevis M, Geyer H, Mareck U, Flenker U, Schanzer W.
From the Center for Preventive Doping Research, Institute of Biochemistry, German Sport University Cologne, Cologne, Germany.

5alpha-Reductase inhibitors such as finasteride are prohibited in sports according to the World Anti-Doping Agency. This class of drugs is used therapeutically to treat benign prostatic hyperplasia, as well as male baldness, by decreasing 5alpha-reductase activity. Accordingly, metabolic pathways of endogenous as well as synthetic steroids are influenced, which complicates the evaluation of steroid profiles in sports drug testing.

The possibility of manipulating steroid excretion profiles and, presumably, to mask steroid abuse was investigated in 5 administration studies with use of finasteride at different doses, with and without coadministration of 19-norandrostenedione. The evaluation of urinary steroid profiles demonstrated the intense effect of finasteride on numerous crucial analytical parameters, in particular the production of 5alpha-steroids such as androsterone and 5alpha-androstane-3alpha,17beta-diol, which was significantly reduced.

In addition, the excretion of the main metabolite of norandrostenedione, norandrosterone, was significantly suppressed, by up to 84%, in elimination studies.

For doping-control analysis the use of 5alpha-reductase inhibitors causes considerable problems because steroid profile parameters, which are commonly considered stable, are highly affected and complicate the detection of steroid abuse. In addition, the suppression of production and renal excretion of 5alpha-steroids such as 19-norandrosterone generated from anabolic agents such as 19-norandrostenedione may lead to false-negative doping-control results, because urine specimens are reported positive only when a threshold level of 2 ng/mL is exceeded.

Finally, a method for the determination of the major urinary metabolite of finasteride (carboxy-finasteride) in routine doping-control screening with use of liquid chromatography-tandem mass spectrometry is described, allowing the detection of carboxy-finasteride for up to 94 hours in urine specimens collected after an oral administration of 5 mg of finasteride.

PMID: 17417080

Researchers in India studied hair loss patterns in 150 male patients who suffer from androgenetic alopecia (AA)

They found the severity of the hair loss increased significantly with age.  They attempted to classify the cases according to the Norwood/Hamilton scale which is a chart grading the severity of hair loss.   They were able to classify 80% of the cases according to the chart, but some did not fit into any of the categories.

This research was done to get some data on MPB within the Indian population which is currently not well documented.

Male pattern androgenetic alopecia in an Indian context: a perspective study.

J Eur Acad Dermatol Venereol. 2007 Apr
Sehgal V, Kak R, Aggarwal A, Srivastava G, Rajput P.
Skin Institute and School of Dermatology, Greater Kailash, New Delhi, India.

Background Androgenetic alopecia (AGA) has received scant attention, despite it being a common entity that may result in significant psychosocial morbidity. There are some patients who do not fit into any of the proposed types. Moreover, there have been no published studies of pattern and prevalence of AGA in males in an Indian context. Hence, the present study was an attempt to classify AGA in males with the aim of producing a simple, effective and easily reproducible classification.

Methods: In total, 150 male patients were clinically diagnosed as AGA. After obtaining informed consent from all patients, a detailed history/examination was carried out, including a hair pull test, a trichogram investigation and a biopsy. Classification of AGA was subsequently attempted across Norwood guidelines.

Results: A gradual shift in the type of AGA from the earlier types (II and III) to more severe types (VI) with increasing age was significant. Twenty-seven patients did not fit into specific patterns according to Hamilton and Norwood classifications. In addition, type ‘a’ variant was recorded in 20% of patients, clearly indicating limitations of the existing classifications.

Conclusions: It was possible to classify 80% of the AGA, with II (28%) and III (15%) being the most common types of AGA. Twenty-seven patients (18%) could not be classified as a significant finding. There was considerable overlap in types IV, V and VI in the Norwood classification with the ‘a’ variants further confusing the picture.

PMID: 17373973

Dr Fischer, who conducted the first trial, took scalp biopsies from 14 men in the early stages of hair loss. He extracted the hair follicles and then placed them in test tubes with solutions containing different levels of caffeine.  The follicles that were being treated with caffeine saw their average growth increase by around 46 per cent and the life cycle of the hair extended by 37 per cent, when compared to the control group.

This study prompted some manufacturers to add caffeine to their hair loss products.

In this study, researchers in Germany wanted to see if topically applied caffeine could be delivered to the follicle when being part of a shampoo.

According to their study they were able to prove that after 2 minutes of shampooing, the caffeine in the shampoo was able to penetrate into the scalp via the hair follicles and stratum corneum (the outermost layer of the skin).

This proves that shampoo is an effective delivery vehicle for caffeine, provided that it’s left on the scalp for 2 minutes or more.

Follicular Penetration of Topically Applied Caffeine via a Shampoo Formulation.

Skin Pharmacol Physiol. 2007 Mar 29;20(4):195-198
Otberg N, Teichmann A, Rasuljev U, Sinkgraven R, Sterry W, Lademann J.
Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Charite-Universitatsmedizin Berlin, Berlin, Germany.

Aims: Follicular drug delivery is the prerequisite for an effective treatment of androgenetic alopecia or other reasons of premature hair loss.

Methods: The follicular penetration of caffeine, applied topically in a shampoo formulation for 2 min, was measured with highly sensitive surface ionization in combination with mass spectroscopy, a selective method for the detection of very small quantities of transcutaneously absorbed substances in the blood. An experimental protocol, developed to selectively block the follicular pathway within the test area, was used. Based on this principle, a clear distinction between interfollicular and follicular penetration of topically applied caffeine was feasible.

Results: After 2 min, caffeine penetrated via the hair follicles and stratum corneum.

Conclusion: It was found that the penetration via hair follicles was faster and higher compared with the interfollicular route and that hair follicles are the only pathway for fast caffeine absorption during the first 20 min after application.

Copyright (c) 2007 S. Karger AG, Basel.

Source: PMID 17396054