Why dandruff can change during pregnancy

“Dandruff” typically reflects seborrheic dermatitis (SD) of the scalp—a chronic, relapsing condition linked to Malassezia yeast, scalp lipid composition, and host inflammation.

Pregnancy alters several SD drivers:

• Sebum & barrier: Estrogen/progesterone shifts can change sebum quantity and composition, and increase transepidermal water loss in some individuals—conditions that favor Malassezia proliferation.

• Immune modulation: Pregnancy skews toward Th2-predominant immunity, which can modify cutaneous inflammatory responses and disease activity.

• Hair cycle changes: Extended anagen in late pregnancy with postpartum telogen effluvium can make flaking more visible after delivery.
  Net effect: some patients flare in 1st–2nd trimester or postpartum; others improve—variability is common.
  Evidence base: While SD-specific pregnancy trials are limited, seborrheic dermatitis is mechanistically tied to Malassezia load and skin barrier/inflammation, all influenced by pregnancy biology.¹²

Key takeaways (for the busy patient)

• Pregnancy can trigger or worsen dandruff/seborrheic dermatitis in some people due to hormonal, immune, and sebum-production shifts.

• Most OTC antifungal shampoos (pyrithione zinc, ketoconazole 1–2%, selenium sulfide 1%) have minimal systemic absorption when used as directed and are generally considered compatible with pregnancy and breastfeeding.

• Avoid or limit coal tar and high-concentration salicylic acid on large areas; use potent topical steroids sparingly and only short term.

• If scale is thick, inflamed, or unresponsive in 4–6 weeks, seek evaluation to exclude psoriasis, tinea capitis, contact dermatitis, or postpartum triggers.

What’s safe to use during pregnancy?

First-line: antifungal shampoos (target Malassezia)

Use 2–3×/week; contact time 3–5 minutes before rinsing. Rotate if needed.

• Pyrithione zinc Shampoo: Minimal percutaneous absorption from shampoos; extensive OTC use history. Considered low risk in pregnancy and lactation when used as directed.²³

• Ketoconazole (1–2% shampoo): Very low systemic absorption from scalp application; generally compatible with pregnancy; safe in breastfeeding with routine precautions (don’t apply where the infant’s skin contacts).²⁴

• Selenium sulfide (1%): Effective for Malassezia. Use on intact scalp, avoid excessive amounts/large body areas. Generally acceptable in pregnancy and breastfeeding.²⁵

• Ciclopirox (1% shampoo): Limited pregnancy-specific data; low absorption; reasonable second-line if others fail.²

Keratolytics (help lift scale)

• Salicylic acid (≤3%): Spot/scalp-limited use appears low risk; avoid large-area, prolonged or occluded use.²⁶

• Urea (5–10%): Softens scale; low systemic absorption; generally safe.

Anti-inflammatory agents

• Topical corticosteroids (low-to-medium potency): Short courses for inflamed flares are reasonable. Large cohort data suggest no major congenital risk overall; however, high-potency steroids in large cumulative amounts may be associated with lower birth weight—use the lowest effective potency, limited duration.⁷

• Topical calcineurin inhibitors (off-label for scalp SD): Minimal systemic absorption; limited pregnancy data; consider when steroids are unsuitable—prefer specialist guidance.²

Agents to avoid or minimize

• Coal tar: Sparse pregnancy data; theoretical teratogenic and carcinogenic concerns from PAHs → generally avoid, especially in 1st trimester.²

• High-concentration salicylic acid peels or large-area applications → avoid.²⁶

• Essential oils (e.g., high-% tea tree oil): Contact dermatitis risk; limited pregnancy data; if used, keep dilute and discontinue with any irritation.²

Breastfeeding considerations

• Shampoo agents have negligible milk transfer with routine scalp use.

• Practical tips: apply after a feed, rinse thoroughly, avoid residue on areas contacting the infant, and wash hands before nursing.²⁴²⁵

Step-by-step regimen (pregnancy-safe)

1. Wash schedule:

   • Mon/Thu: ketoconazole 1–2% or pyrithione zinc 1% (3–5 min contact)

   • Sat: selenium sulfide 1% (3–5 min contact)

   • Other days: gentle, fragrance-light shampoo

2. Scale softening (2–3×/week pre-wash): light mineral oil or urea 5–10% for 10–20 min, then wash.

3. Flares: low-potency steroid solution/foam (e.g., hydrocortisone 1% OTC or prescription class VI–VII) thin layer once daily for 3–5 days, then stop.

4. Maintenance: once controlled, keep 1 medicated wash/week to prevent relapse.

5. If no improvement in 4–6 weeks or atypical features → see your clinician; consider KOH exam, culture, or alternative diagnoses.

Special situations

• Severe, recalcitrant SD: Dermatology referral; short courses of mid-potency steroids or off-label calcineurin inhibitors may be considered.

• Coexistent scalp psoriasis: Prefer steroid solutions/foams short term; avoid coal tar; add antifungal rotation if Malassezia component suspected.

• Postpartum flares: Normalize wash routine; continue safe antifungals; manage coincident telogen effluvium expectations (shedding peaks ~3 months postpartum).

Bottom line

Pregnancy can change scalp oil, immunity, and barrier function—conditions that can trigger or worsen dandruff/seborrheic dermatitis. Most OTC antifungal shampoos used with brief contact times are appropriate in pregnancy and breastfeeding. Build a simple rotation, add gentle keratolytics for scale, and reserve short, low-potency steroids for inflamed flares. Escalate care if the presentation is atypical or unresponsive.

References (selected)

1. Dessinioti C, Katsambas A. Seborrheic dermatitis: etiology, risk factors, and treatments: facts and controversies. Clin Dermatol. 2013;31(4):343–351.

2. Kroumpouzos G, Cohen LM. Specific dermatoses of pregnancy and their treatment. In: UpToDate (continuously updated clinical review).

3. Del Rosso JQ, Bikowski JB. Management of seborrheic dermatitis and dandruff: a practical overview. J Clin Aesthet Dermatol. 2010;3(11):44–48.

4. LactMed Database. Ketoconazole (topical)—Drugs and Lactation Database (NIH). Accessed 2024.

5. LactMed Database. Selenium sulfide (topical)—Drugs and Lactation Database (NIH). Accessed 2024.

6. MotherToBaby Fact Sheets (OTIS). Salicylic Acid (Topical); Ketoconazole (Topical); Selenium Sulfide. Updated 2022–2024.

7. Chi CC, et al. Topical corticosteroid use during pregnancy and risk of low birthweight: population-based cohort. JAMA Dermatol. 2013;149(11):1274–1280.

8. Cochrane Skin Group. Antifungal treatments for seborrhoeic dermatitis of the scalp (review). Cochrane Database Syst Rev. 2015;(5):CD011380.

9. American Academy of Dermatology. Seborrheic dermatitis: overview and treatment (patient/clinician guidance). Updated 2022.