Moderate
Budesonide × isotretinoin
Inhaled corticosteroids (ICS)×Systemic retinoid (vitamin A derivative)
Mechanism
Dual immunomodulation. Isotretinoin is teratogenic and affects liver function and skin barrier. Systemic budesonide suppresses immunity and raises infection risk. No direct pharmacokinetic interaction.
Symptoms
On long-term combination: increased infection susceptibility (bacterial sinusitis, pneumonia, candidiasis). Skin and mucosal dryness intensifies. Cases of intestinal mucosal ulceration on the combination have been reported.
Management
Systemic budesonide and isotretinoin are not co-prescribed without strong indication. In inflammatory bowel disease (Crohn's) with severe acne, options: treat acne topically and with adapalene, or start isotretinoin after inflammation remits and glucocorticoids are stopped. Inhaled budesonide with isotretinoin is safe.