Drug transport can be thought of as the AD&E in ADME, as transporters are responsible for absorption, distribution, tissue-specific drug targeting, and elimination of drugs. Since they are involved in so much of the movement of a compound through the body, they can be involved in many drug‒drug interactions (DDI). The clearance of transporter substrates can be impacted by transporter inhibitors or inducers which can lead to toxicity or loss of efficacy.