Editing Mentha pulegium (section)

===Structure and reactivity===
[[File:Pulegon.svg|thumb|left|110px|Pulegone]]
The active chemical in pennyroyal is pulegone. Pulegone is a [[ketone]] and on the cellular level, ketones can act as [[enzyme inhibitor]]s. The carbonyl center of the pulegone structure acts as a strong electrophile, causing active sites on enzymes to bind with pulegone instead of the target protein.

The exocyclic [[double bond]] found in pulegone is vital to the activation and binding mechanism of the molecule and causes it to be an effective [[hepatotoxin]]. When ingested, pulegone targets the liver and kidney, among other organs. Studies conducted on rats show that one of the main effects is the inhibition of contractile activity in the [[myometrium]] and death by [[kidney failure]]. The studies also found that long-term exposure to pennyroyal increased incidences of urinary bladder tumors.<ref name="ReferenceA"/>