The hair cycle has 3 main phases: the growth phase which takes about 2-7 years, the transition phase which takes about 3 weeks, and the resting phase which usually takes 3 months and there is no noticeable growth. Hair is usually in the growth phase 85-90% of the time.
There are four main types of hair loss:
- androgenic alopecia
- pattern hair loss
- alopecia areata
- telogen effluvium.
This type of hair loss is caused by the presence of androgen dihydrotestosterone. This is a common type of hair loss that occurs between the ages of 12 to 40, but the hair loss is relatively unnoticeable. However, half of these individuals will experience noticeable hair loss
around the age of 50. Women have been found to have higher levels of 5 alpha-reductase which is an enzyme that converts testosterone to dihydrotestosterone, which causes more androgen receptors. Most women who have this type of hair loss will have normal fertility,
normal endocrine function, and normal menses. This type of hair loss is technically treatable and may be reversed, but advanced stages may not be able to respond to treatment.
Pattern Hair loss:
This type of hair loss in women has a mechanism of action that involves several genes. This also involves the progression of hair follicle miniaturization and the conversion of follicles into shorter hair follicles. One of the most common comorbidities associated with this type of hair loss in women is polycystic ovarian syndrome. Other comorbid conditions associated with pattern hair loss are metabolic syndrome, which involves obesity, insulin resistance, and hypertension commonly.
This type of hair loss is an autoimmune disorder where hair loss can take various pathways. Hair loss can be in well-defined patches, or it can be total hair loss, however, the most common is hair loss in patches. This type of alopecia is the second most frequent which is non-scarring. This is a complex, immune-mediated disease that is polygenic. This disease has a large correlation to autoimmune diseases such as inflammatory bowel disease, multiple sclerosis, psoriasis, and Type I Diabetes Mellitus. Individuals with these autoimmune diseases often experience alopecia areata. This has to do with the specific area on chromosome 6, the HLA region, which is the most gene-dense region of the genome and encodes specific immune regulators.
This type of hair loss is usually caused by a condition that shifts the distribution of hair follicles. These women who experience this disorder often notice a significant number of loose hairs on their brushes or in the shower. Telogen effluvium may mask other unrecognized androgenetic alopecia.
Signs & Symptoms:
Androgenic alopecia begins with gradual hair loss and does not have any inflammation or scarring present. Women will usually notice thinning of the hair at the front and sides of the head. Some women may also experience severe acne, excessive hair growth, irregular periods, and/ or infertility.
Pattern hair loss presents with hair shedding with little or no reduction in hair volume over the mid to front of the scalp. This type of hair loss is usually contributed to pre-existing conditions such as abnormal ovaries, menstrual irregularities, acne, and infertility.
Alopecia areata presents with a single oval patch or multiple patches of asymptomatic and non-scarred alopecia. Most patients are generally healthy, but some do present with comorbid conditions such as thyroid disease and skin loss pigments (vitiligo). This type of hair loss has also been associated with certain leukocyte antigen alleles.
Telogen effluvium commonly begins about 2 to four months after a causative event and lasts for several months. This event includes the most common underlying cause which is stress. This can also occur from some medications and contributing diseases such as thyroid, pituitary, and parathyroid disease. This type of hair loss can also occur in patients who are taking oral contraceptives that have progesterone in them or who recently discontinued an oral contraceptive with estrogen.
Dermatologists will check several things when determining the cause of hair loss. The dermatologists will examine the scalp, nails, and other prominent areas of hair loss. They will also assess the characteristics of hair loss in terms of length of time for hair loss, amount of hair loss, and time to onset of hair loss. The dermatologist will also examine how easily the hair breaks. The patient’s diet, medications, present, and past medical conditions, as well as family history of alopecia, are other important factors to consider for a diagnosis. There are three parts of the physical examination for determining the cause and diagnosis of hair loss.
- The first part is examining whether there is inflammation or redness on the scalp. This is
important to determine whether there is scarring present.
- The second part of the examination is the density and distribution of the hair.
- The third part is to determine the length, shape, and fragility of the hair. A common test utilized is the pull test. For this test, 60 hairs are taken between the thumb, index, and middle fingers, and the hairs are firmly pulled. A negative test results when 6 or fewer hairs are shed, whereas a positive test occurs when more than 6 hairs are shed. For this test to be accurate, the patient should avoid shampooing their hair 24 hours before the test is done.
Contributing Factors & those at risk:
There are various causes and risks for hair loss. 2 main contributing factors are cortisol and sex hormones including androgen and estrogen. Cortisol is the stress hormone in our body that is activated when we encounter a stressor. If this hormone builds up it can damage the way the hair cycle works, which leads to androgenic alopecia, alopecia areata, and telogen effluvium. In terms of sex hormones, androgen plays a large role in the development of hair follicles. Androgens have a stimulatory effect in puberty on the pubic areas, chest hair, and armpit hair. However, androgens have an inhibitory effect on scalp hair, thus causing hair loss in some
patients. Estrogens have also been shown to affect hair growth, by keeping hair in the resting phase. This prevents the hair follicle from completing the whole hair growth cycle.
Sudden weight loss or decreased protein intake can be a contributor to hair loss and an increase in protein can treat this type of hair loss issue. Iron deficiency can also be contributed to hair loss, so making sure there is enough iron in the diet, is important for combating hair loss, especially for menstruating women and vegans or vegetarians who must tailor their diets to obtain enough iron. On the other hand, too much daily intake of selenium, vitamin A and vitamin E may also contribute to hair loss.
Micro-needling has also shown improvements in those with hair loss. This process releases various growth factors that aid in the development of hair growth and activates stem cells. This treatment results in faster hair growth, and a shiny texture and may be effective in those patients who did not respond well to minoxidil.
Androgenic alopecia: The preferred treatment for this type of hair loss is topically administered 2 percent minoxidil. Minoxidil increases the length of time follicles spend in the growth phase of the hair cycle. It also enlarges the hair follicles, while reducing the number of hair follicles that are shed. In the past, exogenous estrogen was utilized as another treatment option for women, but it is used less often due to being less effective than minoxidil.
Alopecia areata: The most common treatment is an injection of triamcinolone acetonide. Hair growth usually occurs within four weeks and treatment can last up to 6 weeks. Oral corticosteroids are not commonly used due to their adverse effects. Sometimes, oral prednisone can be utilized and effective in some patients. Topical minoxidil is another treatment option, but this has not been FDA approved for the treatment of alopecia areata. For those patients with widespread alopecia areata, anthralin can be used. This medication is available in creams that can be applied daily at home. Hair growth is seen normally within 2 to 3 months of treatment.
Pattern hair loss: Both males and females can experience pattern hair loss and the current FDA approved regimen for this is HairMAx Lasercomb device. This has shown to be very effective and increases hair density. Patients have noticed the decreased rate of hair loss,
increased hair thickness and fullness.
Telogen effluvium: The main treatment for this type of hair loss is to recognize the cause of the hair loss and prevent that from happening. For example, one of the primary causes of this type of hair loss is certain medications. So, if a patient is taking one of these contributing medications, then the patient should reach out to their physician or pharmacist in order to determine an alternative therapy that could regrow their hair and prevent hair loss from occurring in the first place.
Compounded medications are another option for treatment and include the following but are not limited to:
- Minoxidil 5% + Progesterone 0.25% + B12 0.07% Melatonin 0.1% CoQ 0.1%
- Minoxidil 10% Biotin 0.2%
- Minoxidil 5% Biotin 0.2% + Finasteride 0.1%
- Minoxidil 5% + Tretinoin 0.01% + Betamethasone 0.025% + Melatonin 0.1%
These compounding medications are available at Homestead Community Pharmacy. Reach out to your physician or pharmacist for more information regarding compounded medications.
Adverse Effects of Treatments:
Minoxidil is listed as a pregnancy category C and should not be used in patients younger than 18 years old. The primary side effect of this medication is excessive hair growth, usually noted on the cheeks and the eyebrows. Triamcinolone acetonide can cause local skin atrophy and oral corticosteroids can cause a whole host of side effects including neurologic effects, and myopathy, and can mask the symptoms of infections. Therefore, oral corticosteroids should be initiated with caution and with a physician’s supervision. Some mild side effects are notable in laser HairMax laser comb devices which include dry skin, itching, tender scalp, and warmth at the site of application.
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