Transporters

Transporters move drugs across membranes. For most compounds you can ignore them. For some, they're the whole story.

Common transporters in Lab

• P-gp (P-glycoprotein) — efflux at the gut + blood-brain barrier
• OATP1B1 — hepatic uptake (statins, some antibiotics)
• OCT2 — renal uptake (metformin)

When transporters matter

• BBB penetration — does the drug reach the brain?
• Hepatic clearance — for statins especially
• Drug-drug interactions via transporter inhibition