Telogen Effluvium — Hair Loss Caused by Stress, Illness, Strain

What is Telogen Effluvium?

Normal hair cycle: 85–90% of follicles are in the anagen phase (growth), 10–15% in the telogen phase (rest). Daily loss: 50–100 hairs.

In telogen effluvium, this cycle is disrupted. A stressful event causes an above-average number of follicles to enter the telogen phase simultaneously. Approximately 2–3 months later (at the end of the telogen phase), these hairs fall out at the same time.

Characteristics

• Diffuse loss over the entire scalp, not localized
• Begins 2–4 months after the trigger
• 200–500 hairs daily (instead of the normal 50–100)
• Positive pull test with 6+ hairs
• No scarring, no inflammation
• Hairline usually preserved
• Reversible once the trigger is removed

Acute vs. Chronic

• Acute telogen effluvium: a single episode, subsides after 3–6 months
• Chronic telogen effluvium: lasts at least 6 months, often more difficult to diagnose

Common Triggers

The key to understanding telogen effluvium is that the trigger typically occurs 2–4 months before visible hair loss. Those unaware of this will look for the trigger in the wrong timeframe.

Physical Triggers

• Major surgeries
• Severe infections (e.g., COVID-19, flu, sepsis)
• High fever over several days
• Childbirth (postpartum telogen effluvium — separate article)
• Rapid weight loss or crash diets
• Development of iron deficiency
• Hyperthyroidism or hypothyroidism
• Starting or stopping birth control pills
• Other hormonal changes

Medication-Induced

• Anticoagulants (heparin, warfarin)
• Beta-blockers
• Lithium
• Antidepressants (some SSRIs)
• Antiepileptics
• High-dose vitamin A preparations
• Retinoids for acne
• Chemotherapy (a special form — see separate article)

Psychological Stress

• Grief, separations
• Burnout, professional overload
• Acute traumatic events
• Chronic fatigue

Nutritional

• Protein deficiency (e.g., with restrictive diets)
• Iron deficiency
• Zinc deficiency
• Vitamin D deficiency
• Selenium deficiency
• After bariatric surgery
• In eating disorders

Differentiation from Other Forms

Telogen effluvium is often confused with other forms — leading to incorrect therapy.

Telogen Effluvium vs. Androgenetic Alopecia

• Onset · Telogen Effluvium: sudden, 2–4 months after trigger · Androgenetic Alopecia: gradual over years
• Distribution · Telogen Effluvium: diffuse, even · Androgenetic Alopecia: crown area / hairline
• Hairline · Telogen Effluvium: preserved · Androgenetic Alopecia: men: receding / women: preserved
• Trichoscopy · Telogen Effluvium: normal, no miniaturization pattern · Androgenetic Alopecia: miniaturization typical
• Pull Test · Telogen Effluvium: positive · Androgenetic Alopecia: often negative
• Course · Telogen Effluvium: reversible · Androgenetic Alopecia: progressive

Telogen Effluvium vs. Alopecia Areata

Alopecia areata: circular, sharply defined bald patches. Telogen effluvium: diffuse thinning without localized boundaries.

Telogen Effluvium vs. Scarring Alopecia

Scarring alopecias show smooth skin areas without follicular openings. Telogen effluvium: follicles are present, but many are in the resting phase.

Special Case: Combined Forms

Very common: telogen effluvium plus androgenetic alopecia. The telogen effluvium "unmasks" the underlying gradual androgenetic loss. When the acute shedding subsides, a persistent thinning sometimes remains — indicating an additional underlying condition.

Diagnosis

Diagnostic Steps

1. Detailed anamnesis with a focus on events 2–6 months before the onset of loss — surgeries, illnesses, medication changes, lifestyle changes, psychological stress
2. Trichoscopy to differentiate from other forms
3. Pull test to quantify current activity
4. Blood analysis — ferritin, vitamin D, B12, zinc, TSH, fT3/fT4, possibly hormone panel
5. If combined components are suspected: extended diagnostics (autoimmune screening, ANA)

Trigger Identification

Identifying the trigger is key to therapy. Patients are often initially unaware of the triggers:

• "What surgery did you have in the last 6 months?"
• "Was there a severe infection?"
• "Have you lost weight?"
• "What new medications are you taking?"
• "What was your stress level like in the last six months?"

If no trigger can be identified and the course lasts longer than 6 months: diagnosis "chronic telogen effluvium" — a distinct entity with its own treatment.

Therapy & Course

The most important therapy is treating the cause:

• Iron deficiency → supplementation
• Thyroid disorder → regulation
• Medication-induced → switch if possible
• Stress-related → stress management, possibly psychotherapeutic support
• Nutritional → dietary correction

Supportive Measures

• Iron supplementation even with borderline ferritin (target > 70 ng/ml)
• Vitamin D to optimal range
• B vitamins if deficient
• Topical hair growth therapy 2% for women, 5% for men — accelerates re-entry into the anagen phase
• PRP therapy as an accelerator of regeneration
• Mesotherapy as a complementary stimulation

Typical Course

• Months 1–3: active shedding, intense loss
• Months 3–6: loss subsides, first regrowth visible
• Months 6–12: noticeable recovery of hair density
• Months 12–18: complete restoration

What patients often need

Reassurance and patience. The fear of "balding" is usually unfounded. However: as long as the trigger is still active (e.g., chronic stress), the course can be prolonged.

Chronic Telogen Effluvium

If hair loss lasts longer than 6 months and no clear trigger can be identified: chronic telogen effluvium. Different clinical picture, different therapy.

Common Characteristics

• Primarily women aged 30–60 years
• Diffuse, fluctuating loss over years
• Sometimes episodes, sometimes stable phases
• Hairline usually preserved
• Normal trichoscopy
• No scarring

Diagnosis in Case of Suspicion

• Extensive hormone diagnostics
• Thyroid function including antibodies
• Autoimmune screening (ANA, Anti-TPO)
• Complete micronutrient status
• Possibly skin biopsy for certainty

Therapy

• Optimization of all micronutrients
• Thyroid optimization
• Long-term topical hair growth therapy
• PRP at regular intervals
• If an additional androgenetic component: anti-androgen therapy in women, DHT inhibitors in postmenopausal women or men
• Stress management, sleep hygiene, lifestyle adjustment

Prognosis

Chronic telogen effluvium can last for years — but usually improves spontaneously or with consistent therapy. Permanent loss is rare. The most important message: despite chronicity, balding usually does not occur.

Frequently Asked Questions

How do I recognize telogen effluvium?

Sudden, severe loss 2–4 months after a stressful event, diffuse over the entire scalp. Pull test positive (over 6 hairs). No circular patches, hairline preserved.

When will I see a normal amount of hair again?

If the trigger is removed: noticeable improvement after 3–6 months, complete restoration after 12–18 months. In chronic form, it may take longer.

Can stress alone cause hair loss?

Yes, definitely. Acute or chronic stress can trigger telogen effluvium. However, other causes (deficiencies, thyroid) should be ruled out.

Will I lose my hair permanently?

In most cases, no. Telogen effluvium is a functional disorder of the hair cycle, not destruction of the follicles. Once the trigger is resolved, the cycle normalizes.

Does topical hair growth therapy help?

Yes, topical hair growth therapy can accelerate re-entry into the anagen phase. Topical 2% for women, 5% for men. Effect can be assessed after 4–6 months.

What is the difference from androgenetic alopecia?

Telogen effluvium: sudden onset, diffuse loss, reversible. Androgenetic: gradual onset, pattern distribution, permanent. Often combined — in which case telogen effluvium unmasks the underlying androgenetic loss.