Like tacrolimus, pimecrolimus belongs to the ascomycin class of macrolactam immunosuppressants and acts by inhibiting T-cell activation via the calcineurin pathway and inhibiting the release of numerous inflammatory cytokines, thereby preventing the cascade of immune and inflammatory signals. At the molecular level, pimecrolimus at nanomolar concentrations inhibits the synthesis of the cytokines interleukin-2 and interferon gamma (Th1 type) and interleukin-4 and interleukin-10 (Th2 type) in human T cells. In addition, pimecrolimus prevents the release of inflammatory cytokines and mediators from mast cells. Pimecrolimus has a similar mode of action to tacrolimus, but is more selective and has no effect on dendritic cells (Langerhans cells).
Due to the low systemic absorption of pimecrolimus after topical application, no reliable information on systemic pharmacokinetic parameters can be given.