What are the oral treatment options for pregnancy rash?

Oral Treatment Options for Pregnancy Rash

Oral prednisolone is the first-line systemic treatment for pregnancy rash, particularly for pemphigus vulgaris, as it is 90% inactivated by the placenta and has no significant increased risk of stillbirth, preterm delivery, or congenital malformations. 1

First-Line Oral Treatment

• Prednisolone is the most commonly used oral treatment for pemphigus in pregnancy, used in 76% of documented cases at doses ranging from 5-300 mg per day 1
• Prednisolone should be preferred over other corticosteroids like betamethasone and dexamethasone, as these are less inactivated by the placenta and could have greater effects on the fetus 1
• When using prednisolone, monitor for potential side effects including intrauterine growth retardation, though the risk is lower than with other corticosteroids 1

Second-Line Oral Treatment Options

• Azathioprine can be used in combination with corticosteroids for pemphigus in pregnancy when prednisolone alone is insufficient 1
• While there are theoretical risks of teratogenicity with azathioprine, these risks are low, and it has been widely used during pregnancy for various autoimmune conditions 1
• Antihistamines may be useful as short-term adjuvants during severe pruritic flares, primarily for their sedative properties 2
  • First-generation antihistamines like chlorphenamine (chlorpheniramine) have a long safety record in pregnancy 1
  • Second-generation antihistamines like loratadine and cetirizine have accumulated sufficient observational data to demonstrate safety 1

Treatments to Avoid During Pregnancy

• Many systemic immunosuppressive agents should be avoided due to known risks to the fetus, including:
  • Mycophenolate mofetil 1
  • Methotrexate 1
  • Cyclophosphamide 1
• Rituximab should be avoided as it crosses the maternofetal barrier, and manufacturers advise against pregnancy for 1 year following therapy 1
• Oral decongestants should be avoided during the first trimester 1

Safe Non-Oral Alternatives for Pregnancy Rash

• Intravenous immunoglobulin (IVIg) is considered safe in pregnancy and has been used successfully in patients with severe pemphigus 1
• Plasmapheresis has been used successfully in some cases, though availability may be limited 1
• Topical treatments are generally safer than systemic medications during pregnancy:
  • Low to mid-potency topical corticosteroids are considered safe 2, 3
  • Emollients should be applied regularly as the basis of therapy 2

Monitoring and Management Considerations

• Close cooperation between dermatologist, obstetrician, and neonatologist is essential when treating pregnancy rash 1
• Monitor for potential neonatal effects, as approximately 45% of neonates born to mothers with pemphigus may have lesions at birth (though these typically resolve within 4 weeks) 1
• Document the extent and severity of the rash at each visit to monitor disease progression and adjust treatment accordingly 2
• Be vigilant for signs of infection, as this is a significant risk factor for mortality in conditions like pemphigus vulgaris 1

Special Considerations

• The first trimester is the most critical time for concern about potential congenital malformations due to medication use 1
• Undertreatment due to fear of medication effects can lead to poor disease control; proper education about risks and benefits is essential 2
• Secondary bacterial infections may require antibiotics such as flucloxacillin, especially for Staphylococcus aureus 2