What is the recommended pharmacological and non‑pharmacological management algorithm for psoriasis in a pregnant woman?

Management Algorithm for Psoriasis in Pregnancy

For pregnant women with psoriasis, low- to moderate-potency topical corticosteroids are the safest first-line treatment for localized disease, while narrowband UVB phototherapy is the preferred systemic treatment for moderate-to-severe disease, with cyclosporine reserved as rescue therapy for severe refractory cases. 1

Step 1: Localized Psoriasis (First-Line Topical Therapy)

Topical corticosteroids are the safest and most appropriate initial treatment for localized psoriasis in pregnancy: 1

• Low- to moderate-potency topical corticosteroids should be used as first-line therapy 1
• Salicylic acid appears safe for localized psoriasis control in pregnancy 2
• Avoid salicylic acid on >20% body surface area due to risk of systemic absorption, particularly in patients with abnormal hepatic or renal function 2
• Do not apply salicylic acid before UVB phototherapy as it decreases efficacy through a filtering effect 2, 1

Contraindicated topical agents:

• Tazarotene is absolutely contraindicated and must be discontinued immediately if pregnancy is recognized 1
• Topical tar products should be avoided due to unclear teratogenic risks 3

Step 2: Moderate-to-Severe Psoriasis (First-Line Systemic Therapy)

Narrowband UVB phototherapy is the first-line systemic treatment when topical therapies fail: 1

• No known teratogenic effects and considered the safest systemic approach during pregnancy 1
• Administered 3-5 times per week with initial dose based on skin type (130-400 mJ/cm²) 1
• Increase by 10% of initial dose for treatments 1-20, with most patients requiring approximately 30 treatments for noticeable response 1
• Use routine genital shielding during phototherapy to avoid potential fetal effects 1
• Pregnancy is not a contraindication to UVB therapy 1

Step 3: Severe Refractory Disease (Rescue Therapy)

Cyclosporine may be used as rescue therapy when phototherapy fails or is impractical: 1, 4

• Starting dose: 2.5 mg/kg/day divided twice daily 1
• Use for short 3-4 month interventional courses to minimize fetal exposure 1
• Benefits to maternal health outweigh potential fetal risks in severe refractory disease 1
• Pregnancy category C: may cause lower birth weight and shorter pregnancy duration, but appears not to be teratogenic 4
• Mothers receiving cyclosporine should not breastfeed 4
• Monitor blood pressure and renal function closely, as hypertension and impaired renal function are known adverse effects 2

Step 4: Biologic Therapy (When Other Options Have Failed)

TNF-α inhibitors may be used with extreme caution when disease severity necessitates treatment: 1

• Adalimumab, etanercept, and infliximab may be considered when other options have failed and disease severity is severe 1
• Most pregnancies in women taking biologics have had successful outcomes 1
• Four of five biologic agents are pregnancy category B (efalizumab is category C) 2

Critical timing considerations for biologics:

• Avoid biologics during first 12 weeks (critical period of fetal development) 1
• Maternal IgG (and biologics) actively transfers to fetus during second and third trimesters with unknown developmental impact 1
• For infliximab specifically: avoid infusions after 30 weeks due to long half-life and placental crossing with persistence in fetal circulation for several months 1
• Infants exposed to biologics beyond 16 weeks gestation should not receive live vaccines until 6 months of age (including rotavirus and BCG) 1
• Effective contraception is strongly recommended for patients receiving biologic therapy 1

Absolutely Contraindicated Treatments

Never use these medications during pregnancy:

• Methotrexate: Known teratogen and mutagen causing fetal death or teratogenic effects 2, 4
• Acitretin: Severe teratogenic effects with long elimination half-life; women must avoid pregnancy for at least 3 years after discontinuing 4
• Apremilast: Insufficient safety data and should not be used during pregnancy 1, 4
• Tazarotene topical: Must be discontinued immediately if pregnancy is recognized 1

Essential Counseling and Monitoring

Key points for patient counseling:

• Controlling severe or unstable psoriasis is important to maintain maternal health 1
• Risk-benefit discussion must be individualized based on disease severity, prior pregnancy outcomes, and patient preferences 1
• Consultation with high-risk maternal-fetal medicine is recommended when considering systemic therapy 1
• Psoriasis generally improves during pregnancy but many patients still require treatment 3
• Worsening typically occurs between 4-6 weeks postpartum 5

Pregnancy monitoring in moderate-to-severe psoriasis:

• High risk of pregnancy complications including pregnancy-induced hypertensive disorders, low birth weight for gestational age, and gestational diabetes 6
• Careful pregnancy monitoring is required for moderate-to-severe psoriasis vulgaris 6

Common Pitfalls to Avoid

• Do not use salicylic acid in combination with other oral salicylate drugs due to risk of systemic toxicity 2
• Do not apply anthralin to face and intertriginous areas due to risk of severe skin irritation 2
• Do not discontinue biologics without considering maternal disease control risks versus potential fetal harm 1
• Do not forget that patients on biologics during pregnancy require evaluation for risks of discontinuing therapy balanced against potential harm to fetus/infant 1