salmeterol: Substrate for CYP 3A4. Probably insignificant metabolic load. Fluticasone: Probably insignificant systemic exposure. Several references stating non-porphyrinogenic metabolism of glucocorticoids.

salmeterol Adrenergic administered in asthma in inhalation aerosol, 50 µg/dose. Gives rise only to very low plasma concentrations. Metabolized in the liver (CYP 3A4) producing several metabolites. fluticasone Antiasthmatic antiinflammatory glucocorticoide, administered as inhalation powder (50 - 250 µg/dose). Systemic exposure about 16% of the taken dose. Rapidly metabolized by CYP 3A4 (within 3-4 hours). glucocorticoides: EPI-list: safe French list: authorized South African list: use Kalman, Bonkowski: safe The Merck Manual: safe Tschudy DP, Lamon JM: safe Moore MR, Hift RJ: safe French list: authorized South African list: use

Uneventful use reported in 7 patients with acute porphyria.