Substrate for several human CYPs. Even if some systemic absorption may take place the concentration of the substance in the creme is quite low and systemic exposure probably low.

Local analgesic; creme 0.075%. Selective analgesic effect in local application, probably through its effect on substance P in the afferent C-fibres. No data on metabolism.

Uneventful use reported in 1 patient with acute porphyria.