What is the best approach to manage telogen effluvium in patients, including those with iron deficiency or hormonal imbalances, and considering various treatment options such as iron supplementation (ferrous sulfate), biotin supplements, low-level laser therapy (LLLT), and platelet-rich plasma (PRP) therapy?

Management of Telogen Effluvium

The primary management of telogen effluvium is identifying and removing the triggering factor, followed by targeted nutritional supplementation when deficiencies are confirmed, with iron replacement being the most evidence-based intervention when iron deficiency is documented. 1, 2

Initial Diagnostic Approach

Identify the precipitating cause through focused history:

• Recent physiological stressors (childbirth, surgery, severe illness, COVID-19 infection) occurring 2-4 months prior to hair loss onset 2, 3
• Medications known to trigger telogen effluvium (particularly azithromycin and ivermectin, which show association with post-COVID hair loss) 3
• Thyroid dysfunction, inflammatory conditions, or rapid weight loss 4, 2

Perform targeted laboratory evaluation:

• Complete blood count with MCV and RDW (MCV/RDW ratio is lower in telogen effluvium patients) 5
• Serum ferritin (though note: ferritin may be elevated post-COVID due to inflammation, limiting its diagnostic utility in post-viral telogen effluvium) 3
• Thyroid function tests (TSH, free T4) 4
• Vitamin B12 level 4

Clinical examination findings:

• Positive hair pull test (>6 hairs extracted from 60 hairs grasped) 2
• Dermoscopic examination showing increased telogen hairs without miniaturization 4

Treatment Algorithm

Step 1: Remove Causative Factors

Discontinue or modify triggering medications and address underlying medical conditions first. 2 This is the most critical intervention, as telogen effluvium is typically self-limited once the trigger is removed.

Step 2: Iron Replacement (When Deficiency Confirmed)

For documented iron deficiency (ferritin <45 μg/L or <100 μg/L with transferrin saturation <20%):

Oral iron supplementation (first-line):

• Start with ferrous sulfate 200 mg once daily (65 mg elemental iron) 1
• Alternative formulations: ferrous fumarate or ferrous gluconate are equally effective 6, 1
• Continue for 3 months after hemoglobin normalization to replenish iron stores 6, 1
• Expect hemoglobin rise of 2 g/dL after 3-4 weeks 6, 1

Enhance absorption:

• Take with 250-500 mg ascorbic acid (vitamin C) to improve iron absorption 6, 1
• Administer on empty stomach when tolerated, or with meat protein if gastrointestinal side effects occur 6

Parenteral iron (when oral fails):

• Indications: intolerance to at least two oral preparations, non-compliance, malabsorption, or continued blood loss 6, 1
• Ferric carboxymaltose (Ferinject) 1000 mg over 15 minutes is preferred for convenience and safety 1
• Alternative: Iron sucrose 200 mg over 10 minutes 1
• Recheck labs 8-10 weeks post-infusion (ferritin falsely elevated immediately after) 1

Step 3: Nutritional Supplementation

The evidence for routine supplementation is weak, but targeted therapy may be considered:

When zinc deficiency is suspected or confirmed:

• Zinc levels are significantly lower in chronic telogen effluvium patients 4
• Consider zinc supplementation as part of a comprehensive nutritional approach 7

Multi-nutrient supplementation (limited evidence):

• A combination of zinc, biotin, iron, vitamins A, C, E, B complex, folic acid, magnesium, and amino acids showed clinical improvement at 90 days in one comparative study 7
• However, a 2024 case-control study found no significant differences in vitamin D, vitamin B12, biotin, or copper levels between telogen effluvium patients and controls 4

Preventive supplementation during acute illness:

• Vitamin C, vitamin D, lactoferrin, and zinc used during active COVID-19 infection may have preventive value against post-COVID telogen effluvium 3

Step 4: Adjunctive Therapies (Limited Evidence)

Topical minoxidil:

• May accelerate recovery by promoting telogen-to-anagen transition 2
• Consider for chronic or severe cases, though evidence specific to telogen effluvium is limited 2

Corticosteroids:

• Reserved for cases with significant inflammatory component 2

Novel treatments (insufficient evidence):

• CNPDA formulation (caffeine, niacinamide, panthenol, dimethicone, acrylate polymer) has been proposed 2
• Platelet-rich plasma (PRP) and low-level laser therapy (LLLT) are primarily studied for androgenetic alopecia, not telogen effluvium 6

Monitoring and Follow-Up

Short-term monitoring:

• Reassess at 3-4 weeks to confirm hemoglobin response if iron deficiency was treated 6, 1
• Clinical improvement typically begins 3-6 months after trigger removal 2

Long-term monitoring:

• Monitor hemoglobin and red cell indices every 3 months for the first year, then annually 6, 1
• Reinitiate iron supplementation if hemoglobin or MCV falls below normal 6, 1

Critical Pitfalls to Avoid

Do not routinely supplement without documented deficiencies:

• Recent evidence shows nutritional deficiencies are not as common as previously thought in telogen effluvium patients 4
• Individualized testing and treatment based on confirmed deficiencies is more appropriate than empiric supplementation 4

Do not rely solely on ferritin in post-inflammatory states:

• Ferritin is an acute phase reactant and may be falsely elevated after COVID-19 or other inflammatory conditions 3
• In post-COVID telogen effluvium, ferritin may not be a reliable biomarker for iron deficiency 3

Do not assume treatment failure is due to inadequate dosing:

• Failure to respond to oral iron is usually due to poor compliance, misdiagnosis, continued blood loss, or malabsorption—not inadequate dosing 6, 1

Do not use modified-release iron preparations:

• These formulations have unpredictable absorption and are less suitable 1

Do not overlook medication review:

• Azithromycin and ivermectin show negative associations with post-COVID hair recovery 3