Hair Loss Is Not a Single Diagnosis

Hair loss can develop gradually or suddenly and may appear as progressive thinning, excessive shedding, recession of the hairline, discrete patches of hair loss, breakage, or inflammation of the scalp. Some forms of hair loss are primarily genetic, while others may be related to hormones, autoimmune disease, inflammation, nutritional deficiencies, medications, medical illness, or significant physiologic stress.

Because different conditions can look remarkably similar, identifying the type of hair loss is an important first step toward choosing the right treatment.

At Carabella Dermatology, we evaluate both common and complex hair and scalp disorders using a detailed medical and family history, clinical examination, trichoscopy, standardized photography, review of laboratory testing, and additional diagnostic evaluation when appropriate.

Female Pattern Hair Loss

Female pattern hair loss, also known as androgenetic alopecia, is one of the most common causes of progressive thinning in women. Patients may notice widening of the central part, decreased density over the crown, a smaller ponytail, increased visibility of the scalp, or a gradual reduction in overall hair volume.

Genetics, age, hormonal influences, and individual follicular sensitivity may all contribute. Trichoscopy can be particularly helpful in identifying follicular miniaturization and distinguishing female pattern hair loss from other causes of diffuse shedding.

Treatment is individualized and may include prescription medications, customized topical therapies, procedural treatments, and supportive nutritional or scalp-care recommendations depending on the patient’s medical history and goals.

Male Pattern Hair Loss

Male pattern hair loss is another form of androgenetic alopecia and commonly presents with recession at the temples, thinning of the crown, or progressive loss across the top of the scalp.

The underlying process involves gradual miniaturization of susceptible hair follicles. Because this process progresses over time, earlier evaluation may provide more opportunities to preserve existing follicles and discuss medical or restorative treatment options.

Telogen Effluvium

Telogen effluvium is a common cause of increased hair shedding that occurs when a larger-than-normal number of hairs transition into the resting, or telogen, phase of the hair cycle.

It may develop several weeks to months after a significant physiologic stressor such as illness, surgery, childbirth, rapid weight loss, major dietary change, nutritional deficiency, medication change, or significant systemic stress.

Patients often describe suddenly noticing substantially more hair in the shower, on their clothing, in their brush, or when running their hands through their hair.

Evaluation focuses on identifying potential triggers, determining whether another type of hair loss may be occurring simultaneously, and addressing reversible contributing factors when they are identified.

Chronic Telogen Effluvium & Persistent Shedding

Chronic telogen effluvium is characterized by persistent or recurrent diffuse hair shedding, often fluctuating over many months or years. Classic descriptions have emphasized its occurrence predominantly in women, frequently with relatively preserved overall hair density despite periods of striking shedding. The onset may be abrupt, and some patients cannot identify a clear initiating event. 

Chronic telogen effluvium has historically been described as a clinical entity distinct from ordinary acute telogen effluvium and from female pattern hair loss. One important distinction is that patients with chronic telogen effluvium may continue to shed substantially without developing the degree of progressive follicular miniaturization characteristic of androgenetic alopecia. Histologic studies included in a recent systematic review generally demonstrated preservation of the terminal-to-vellus hair ratio in patients diagnosed with chronic telogen effluvium. 

Trichoscopy is particularly valuable in this setting. Female pattern hair loss and chronic telogen effluvium can both present with diffuse thinning or shedding, but the follicular miniaturization, variation in hair-shaft diameter, increased vellus hairs, and other trichoscopic features associated with androgenetic alopecia can help distinguish the conditions. 

The distinction is not always straightforward. A 2023 systematic review oted that chronic telogen effluvium remains incompletely characterized and that some patients assigned this diagnosis may instead have early female pattern hair loss or an unidentified secondary cause of persistent telogen shedding. 

For this reason, persistent shedding deserves a thoughtful evaluation rather than automatically being labeled chronic telogen effluvium. We review the pattern and duration of shedding, medications, nutrition, medical history, laboratory findings, family history, and trichoscopic features to help distinguish chronic telogen effluvium from early androgenetic alopecia and other potential causes.

Postpartum Hair Loss

Postpartum hair loss is a form of telogen shedding that commonly develops several months after delivery as hair follicles adjust to the hormonal changes that follow pregnancy.

For many women, the shedding gradually improves as the hair cycle normalizes. However, particularly prolonged or severe postpartum shedding may warrant evaluation for additional contributing factors, including iron deficiency, thyroid abnormalities, nutritional issues, or underlying female pattern hair loss that may become more apparent after pregnancy.

Alopecia Areata

Alopecia areata is an autoimmune form of hair loss in which the immune system targets the hair follicle.

It most commonly presents with smooth, well-defined patches of hair loss but can range from a few small areas to extensive scalp or body-hair involvement. Eyebrows and eyelashes may also be affected.

Trichoscopy can reveal characteristic findings and can help assess disease activity. Treatment is individualized according to the location, extent, duration, activity, age of the patient, and impact of the condition.

Frontal Fibrosing Alopecia

Frontal fibrosing alopecia, or FFA, is an inflammatory form of scarring alopecia that deserves particular attention because progressive inflammation can permanently damage hair follicles.

FFA most commonly affects women, particularly during and after menopause, although it can occur in younger women and occasionally in men.

One of the earliest signs may be subtle recession of the frontal or temporal hairline. Patients may initially believe that their forehead is simply becoming larger or that their hairline is changing with age. Eyebrow thinning or complete eyebrow loss is also common and may occasionally precede obvious scalp hair loss.

Some patients develop loss of hair on the arms, legs, or other body areas. Small facial papules or changes in facial skin texture may also occur.

The disease can progress slowly, which means early changes may be easy to overlook. This is especially important because once follicles are destroyed by the scarring inflammatory process, regrowth from those follicles is generally not expected.

During evaluation, we carefully examine the frontal and temporal hairline and use trichoscopy to look for signs of active inflammation surrounding individual follicles as well as loss of follicular openings and other characteristic changes.

Standardized photography is particularly useful in FFA because small changes in the position and density of the hairline may otherwise be difficult to appreciate over time.

In selected patients, a scalp biopsy may be recommended to confirm the diagnosis or distinguish frontal fibrosing alopecia from other forms of hair loss.

Treatment is individualized according to the extent and activity of disease, associated symptoms, medical history, and patient preferences. Because FFA is a scarring alopecia, the primary goal of treatment is typically to control inflammation and preserve the follicles that remain.

Lichen Planopilaris

Lichen planopilaris is another inflammatory form of scarring alopecia that can cause patchy or progressive hair loss.

Patients may experience itching, burning, scalp tenderness, redness, or scaling around individual hair follicles, although some patients have relatively few symptoms.

Because inflammation can permanently damage the follicle, identifying active disease and controlling inflammation are important treatment goals. Trichoscopy and, in selected cases, scalp biopsy may help establish the diagnosis.

Central Centrifugal Cicatricial Alopecia

Central centrifugal cicatricial alopecia, or CCCA, is a form of scarring hair loss that typically begins in the central or crown region of the scalp and gradually expands outward.

Patients may notice progressive thinning and may also experience itching, burning, tenderness, or other scalp symptoms.

Early recognition is particularly important because ongoing inflammation can lead to permanent follicular loss. Evaluation may include clinical examination, trichoscopy, standardized photography, and scalp biopsy when the diagnosis is uncertain.

Discoid Lupus & Lupus-Related Hair Loss

Lupus can affect the hair in several different ways.

Systemic illness or inflammation may contribute to diffuse shedding, while cutaneous forms of lupus can directly involve the scalp and produce inflammatory lesions that may result in permanent scarring hair loss.

Discoid lupus of the scalp may present with areas of inflammation, scale, pigmentary change, loss of follicular openings, and progressive alopecia.

When lupus-related or other inflammatory scarring alopecia is suspected, trichoscopy and scalp biopsy may be particularly useful in establishing the diagnosis and guiding treatment.

Hair Loss Associated With Autoimmune Disease

Hair changes may also occur in association with other autoimmune and inflammatory conditions.

Autoimmune disease can influence the hair cycle indirectly through systemic inflammation or illness, or it may directly target the hair follicle or scalp.

A detailed medical history is therefore particularly important when evaluating hair loss in patients with known autoimmune disease or other systemic symptoms.

Traction Alopecia

Traction alopecia develops when repeated tension is placed on the hair follicles over time.

Tight ponytails, braids, extensions, weaves, tight buns, and other styling practices can contribute, particularly when tension repeatedly affects the same areas of the scalp.

Early traction alopecia may improve when the source of tension is identified and modified. Longstanding traction, however, can eventually lead to scarring and permanent loss of affected follicles.

The hairline and temporal scalp are commonly affected, although the pattern varies according to styling practices.

Dissecting Cellulitis of the Scalp

Dissecting cellulitis of the scalp is a chronic inflammatory disorder that can cause painful nodules, pustules, draining areas, interconnected inflammatory lesions, and eventually scarring hair loss.

This is very different from routine pattern hair loss and generally requires treatment directed at controlling the underlying inflammatory process.

Patients experiencing painful scalp nodules, drainage, recurrent pustules, significant tenderness, or progressive areas of scarring hair loss should have the scalp evaluated rather than treating the condition as ordinary thinning.

Iron Deficiency & Nutritional Hair Loss

Healthy hair growth depends upon adequate nutritional support.

Iron deficiency is one potential contributor to excessive shedding and may be particularly relevant in patients with heavy menstrual bleeding, limited dietary iron intake, pregnancy-related changes, gastrointestinal disease, or other risk factors for iron deficiency.

Other nutritional deficiencies or inadequate caloric and protein intake may also influence the hair cycle depending upon the individual patient’s circumstances.

Laboratory results must be interpreted in the context of the patient’s overall history rather than assuming that every laboratory value outside an ideal range is responsible for hair loss.

For this reason, we do not recommend the same supplement regimen for every patient. Nutritional and supplementation recommendations are individualized according to medical history, dietary pattern, laboratory findings, and diagnosis.

Thyroid-Related Hair Loss

Both hypothyroidism and hyperthyroidism can affect the normal hair-growth cycle and contribute to diffuse thinning or increased shedding.

When a patient’s history or clinical presentation raises concern for thyroid dysfunction, appropriate laboratory testing may be considered as part of the overall hair-loss evaluation.

Even when thyroid disease is present, it is important to determine whether it fully explains the hair changes or whether another hair-loss condition may be occurring simultaneously.

Hair Loss Related to Medical Illness or Physiologic Stress

Significant illness, infection, hospitalization, surgery, fever, rapid weight change, and other major physiologic stressors can alter the normal hair cycle and trigger telogen effluvium.

Because shedding frequently begins weeks to months after the precipitating event, patients may not immediately recognize the connection.

Establishing a detailed timeline can therefore be particularly helpful in determining whether a recent medical event may be contributing.

Medication-Related Hair Loss

Certain medications can contribute to increased shedding, changes in the hair-growth cycle, or other forms of hair loss.

As part of a comprehensive evaluation, we review current medications as well as relevant medications that have recently been started, stopped, or changed.

A medication should not be discontinued simply because hair loss is suspected. Instead, the potential relationship should be considered in the context of the patient’s medical needs, timing of symptoms, and other possible causes.

Chemotherapy-Related Hair Loss

Many chemotherapy medications interfere with rapidly dividing hair-follicle cells and can result in abrupt hair loss known as anagen effluvium.

For many patients, hair growth resumes after chemotherapy has been completed, although the timing, texture, color, density, and pattern of regrowth may differ from the patient’s previous hair.

Some patients continue to experience reduced density or altered hair growth after treatment. Persistent chemotherapy-induced alopecia has also been described with certain treatment regimens.

When hair does not recover as expected, evaluation can help determine whether persistent treatment-related changes are present or whether another condition, such as androgenetic alopecia, nutritional deficiency, thyroid disease, or chronic shedding, may also be contributing.

Hair Shaft Breakage & Other Causes of Hair Loss

Not every decrease in apparent hair density represents loss of the follicle itself.

Hair-shaft breakage, chemical or heat damage, inflammatory scalp conditions, infections, genetic hair-shaft disorders, and other less common conditions may cause the hair to appear thinner or shorter.

A careful examination helps distinguish true shedding from breakage and determines whether the problem primarily involves the follicle, scalp, or hair shaft.

Not Sure Which Type of Hair Loss You Have?