Alopecia: Hormonal and Hereditary Factors

Patients with hair loss need to be educated about the possible causes, guided in the proper selection of hair loss products, and directed to seek medical care.

Individuals normally lose 50 to 100 hairs per day. However, there is often cause for concern when individuals notice thinning of hair or significant hair loss after combing or brushing their hair.¹

Studies have revealed that significant hair loss can negatively affect an individual’s self-esteem and cause feelings of embarrassment in some people.¹ Every year, the public spends millions of dollars on products marketed to restore hair growth, putting pharmacists in a pivotal position to educate patients about the causes of hair loss, guide them in the proper selection of hair loss products, and direct them to seek further medical care when warranted.

Androgenetic alopecia, also called pattern hereditary hair loss, is the most prevalent type of hair loss, affecting males and females.^1-3 The American Academy of Dermatology has estimated that 80 million males and females have some degree of androgenetic alopecia.² Research indicates that common etiologies include hormonal and hereditary factors.^1-3 The FDA has approved the use of nonprescription hair loss products only for androgenetic alopecia.³ While this type of hair loss can affect anyone, certain individuals are at greater risk for developing it (Table1^1-7).

Signs and Symptoms

Unlike other types of hair loss, androgenetic alopecia is not associated with inflammation or scarring, and the onset of hair loss is gradual.^1-4 In males, androgenetic alopecia typically begins with gradual hair loss or thinning that often appears at the temples and crown of the head.^1-4 In some cases, males may experience partial or complete baldness.³ Females typically experience diffuse hair thinning on all areas of the scalp, but the hairline does not recede.^3,4 Females presenting with signs of this type of hair loss may also present with severe acne, hirsutism, menstrual irregularities, and infertility due to hyperandrogenism.³ Before using any products for hair loss, affected females or females with signs of hyperandrogenism should be referred for medical evaluation to identify the underlying cause because androgen excess in females may indicate a more serious condition, such as metabolic syndrome or polycystic ovarian syndrome.³

Nonprescription Products

The only FDA-approved nonprescription products available for treating androgenetic alopecia are hydroalcoholic topical solutions of minoxidil in concentrations of 2% and 5% and in a 5% solvent-free foam (Table 2). Topical minoxidil is indicated for the treatment of baldness at the crown of the head in men and for thinning of hair at the frontoparietal region in women.^3,8,9 While its exact mechanism of action is unknown, minoxidil is thought to (1) augment cutaneous blood flow directly to the hair follicles, which enlarge after treatment, and (2) promote and maintain vascularization of hair follicles affected by alopecia.³ While not well documented, some individuals with other types of hair loss, such as alopecia areata, have reported some success with the use of topical minoxidil as well.³ Topical minoxidil 2% can be used in males and females, but the use of 5% topical minoxidil is indicated for use in males only because its use in women may cause facial hair growth.³

No known drug interactions are associated with the use of topical minoxidil; however, it is important to note that the concurrent use of minoxidil with guanethidine may increase the incidence of orthostatic hypotension, and concurrent use of oral minoxidil may augment systemic concentrations and potentiate its effects.³ Systemic adverse effects are rare because minoxidil is absorbed through the skin in low concentrations.^3,9 The most common adverse reactions include itching, dryness, and irritation of the scalp at the site of application.^3,8,9 Transient hypertrichosis is the most common adverse effect associated with long-term use of topical minoxidil.^3,9 Patients should be told that minoxidil should be used only by individuals 18 years and older, and the Pregnancy Category C details regarding minoxidil should be provided to patients in terms they can understand.^3,8,9 During counseling, patients with sudden hair loss or nonpattern hair loss should be encouraged to seek medical advice before using minoxidil products.

Endnote

Prior to recommending the use of these OTC products, pharmacists should review a patient’s medication profile to identify pharmacologic agents that may be associated with increased risk for hair loss. Prior to recommending the use of topical minoxidil products, it is important to ascertain whether self-treatment is appropriate (Table 3³) and if the cause of hair loss has been identified. Patients should always be referred to their primary care physician for further evaluation if the cause of hair loss is unknown or if hair loss is abrupt in onset and/or is severe. It is important for women with sudden and significant hair loss to see their physician for further evaluation and to identify causes or contributing factors.³

Patients should be counseled on how to properly apply topical minoxidil, reminded to adhere to the manufacturer recommendations, and educated about the importance of regularly using the product to maintain regrowth of hair.^3,8 Because discontinuation of treatment produces rapid reversion to the pretreatment balding pattern, regular topical treatment is critical to maintain regrowth of hair.^3,8

Patients should be advised to apply topical minoxidil no more than twice daily and not to apply it to damaged or inflamed skin.^3,8 The product should not be applied 24 hours before or after applying a color, relaxer, or permanent to the hair.^3,8 Pharmacists should inform patients that minoxidil may not be effective for everyone and that it is a suppressive therapy—not a cure.³ Patients should be advised that hair growth may take up to 4 months after initiation of therapy.³ If hair growth does not occur after 4 months of consistent use, patients should be advised to discuss other possible treatments with their primary health care provider. Because hair loss may cause emotional distress and affect self-esteem, health care professionals should be supportive of and empathetic toward affected patients.

Ms. Terrie is a clinical pharmacy writer based in Haymarket, Virginia.

References:

• Hair loss. American Academy of Dermatology website. www.aad.org/media-resources/stats-and-facts/conditions/hair-loss. Accessed September 3, 2014.
• Alopecia. American Academy of Dermatology website. www.aad.org/dermatology-a-to-z/diseases-and-treatments/e---h/hair-loss. Accessed September 3, 2014.
• Berry T. Hair loss. In: Krinsky D, Berardi R, Ferreri S, et al, eds. Handbook of Nonprescription Drugs. 17th ed. Washington, DC: American Pharmacists Association; 2012.
• Alopecia. The Merck Manual Professional Edition online. www.merck.com/mmpe/sec10/ch124/ch124b.html?qt=minoxidil&alt=sh#sec10-ch124-ch124b-975. Accessed September 3, 2014.
• Feinstein R. Androgenetic alopecia treatment & medication. Medscape website. http://emedicine.medscape.com/article/1070167-treatment. Accessed September 3, 2014.
• Causes of hair loss. American Hair Loss Association website. www.americanhairloss.org/women_hair_loss/causes_of_hair_loss.asp. Accessed September 3, 2014.
• Understanding hair loss. McNeil-PPC website. www.rogaine.com/men/understanding-hair-loss. Accessed September 3, 2014.
• How do Rogaine products work? McNeil-PPC website. www.rogaine.com/category/facts/how+it+works.do?nType=2. Accessed September 3, 2014.
• Minoxidil topical. Medscape website. http://reference.medscape.com/drug/rogaine-minoxidil-topical-343548. Accessed September 3, 2014.