The expression of P-glycoprotein can be regulated at the genetic and environmental levels. Genetic polymorphisms in the ABCB1 gene can lead to variations in P-gp expression and function, influencing individual responses to drugs. Environmental factors such as exposure to chemicals, diet, and inflammation can also modulate P-gp levels. Inducers such as rifampicin and St. John's Wort can increase P-gp expression, potentially reducing drug efficacy, while inhibitors can decrease its expression, affecting drug clearance.
