Telogen Effluvium (Severe Hair Loss): Causes, Diagnosis, and Treatment

What is telogen effluvium?

Telogen effluvium is a condition of hair loss that occurs when more hair follicles than normal enter the resting and shedding phases of the hair cycle. It is usually widespread and does not leave scars. Hair loss is often noticed approximately 2–3 months after the triggering event.

How is telogen effluvium diagnosed?

The most typical complaint is significant hair loss across the scalp. Noticeable hair regrowth and decreased hair volume may be observed in the shower, while brushing, drying, or on the pillow.

How many hairs normally fall out per day?

The American Academy of Dermatology (AAD) states that it is normal for healthy individuals to lose approximately 50–100 strands of hair daily. Counting hair at home every day is not necessary or reliable for diagnosis.

What causes telogen effluvium?

Infections accompanied by high fever

Severe systemic diseases

Major surgical procedures

Birth

Rapid and noticeable weight loss

Severe calorie or protein restriction

Starting or stopping certain medications

Certain nutritional problems such as iron deficiency

Thyroid diseases

intense physical or psychological stress

What causes hair loss after childbirth?

During pregnancy, hormonal effects can cause more hair to remain in the growth phase. After childbirth, a significant portion of this hair may transition to the telogen phase, leading to noticeable hair loss a few months later.

Can hair loss occur after infections?

Yes. High-fever infections and severe systemic illnesses can trigger telogen effluvium. An increase has also been reported following Coronavirus Disease 2019 (COVID-19).

Does stress cause hair loss?

Intense psychological stress can be a trigger; however, it is not accurate to explain hair loss solely as being due to "stress".

Iron and vitamin deficiencies

Iron deficiency should be considered during the evaluation. Automatically prescribing vitamin supplements to every patient is not appropriate. Supplements should be used based on laboratory findings and clinical necessity.

Can rapid weight loss trigger hair loss?

Yes. Very low-calorie diets, rapid weight loss, and insufficient protein intake can affect the hair cycle.

How long does telogen effluvium last?

Acute telogen effluvium is usually temporary. Hair loss subsides once the trigger is removed; recovery of hair density can take months.

What is chronic telogen effluvium?

Chronic telogen effluvium may be considered in some patients with hair loss lasting longer than 6 months. Differential diagnosis with androgenetic alopecia is important, and the two conditions may coexist.

What is the difference between telogen effluvium and androgenetic alopecia?

Telogen effluvium is characterized by severe hair loss, while androgenetic alopecia is characterized by miniaturization and thinning of hair strands over time.

How is telogen effluvium diagnosed?

A detailed history, dermatological examination, and trichoscopy if necessary are important. Information regarding illnesses experienced in the last 3–6 months, fever, surgery, childbirth, weight loss, diet, medications, menstrual cycle, thyroid disorders, iron deficiency, and family history may be requested.

Are the same blood tests performed on every patient?

No. Depending on the clinical situation, a complete blood count, ferritin/iron parameters, thyroid function tests, and other tests may be ordered as needed.

How is telogen effluvium treated?

The most important step is to identify and correct the triggering cause, if possible. Acute telogen effluvium, once its trigger has been eliminated, often resolves spontaneously.

Can minoxidil be used in telogen effluvium?

Not every patient needs minoxidil. If there is chronic hair loss or concomitant androgenetic alopecia, it may be considered after a dermatological evaluation.

Do I need platelet-rich plasma (PRP) or mesotherapy?

Platelet-rich plasma (PRP) or mesotherapy is not the standard treatment for every patient with telogen effluvium. The underlying cause must be determined first.

Does cutting hair short or washing it less often reduce hair loss?

No. Reducing hair length doesn't alter the hair follicle cycle. A significant portion of the hair seen during washing is already in the shedding phase.

Does telogen effluvium cause permanent baldness?

Typical acute telogen effluvium alone does not usually cause permanent baldness. However, it may be indicative of androgenetic alopecia or another hair disease.

When should you consult a dermatologist?

If hair loss has started to become very intense

If hair loss lasts longer than a few months

If there is a significant decrease in hair volume

If there is progressive thinning at the hairline or crown area

If completely open areas are created in the region

If there is redness, pain, scaling, or itching on the scalp

If there is also hair loss in eyebrows or body hair

If there is a history of rapid weight loss or severe dieting

If accompanied by menstrual irregularities or hormonal symptoms

Frequently Asked Questions

When does telogen effluvium begin? Most often, about 2–3 months after the triggering event.

Will it completely resolve? Most acute cases resolve, but it may take months for hair volume to regain.

Should I take biotin? High doses of biotin are not routinely recommended without a proven deficiency.

Does the white patches at the ends of falling hair mean the hair follicle is dead? No.

Will it recur? Yes; it can recur if a new trigger develops.

Dermatologist's Note

In cases of severe hair loss, instead of simply turning to products or supplements that "strengthen the hair," it's necessary to determine the type of hair loss and its potential triggers. Telogen effluvium is often reversible; however, androgenetic alopecia, iron deficiency, thyroid disease, or another hair disorder may coexist.