clearance

Introduction

Removal from the systemic circulation & the body

Pharmacology

• renal clearance of a drug by the kidneys with or without prior metabolism by the liver
• hepatic metabolism with biliary elimination
• elimination in the bile unchanged
• small molecules may be eliminated through respiration

Also see pharmacokinetics. Clinical significiance:

• drugs are eliminated either unchanged or as metabolites
• more polar compounds are eliminated more efficiently by excretory organs* than lipopilic compounds
• lipophilic compounds are metabolized to more polar compounds (see drug metabolism)
• lung is important for clearance of volatile drugs (i.e. inhalation anesthetics)
• polar compounds (unchanged drug & or metabolites) are excreted in the urine or bile

* kidney, liver (via bile), breast (lactating), excluding lung sweat, saliva & tears generally unimportant route of clearance

More specific terms

• glymphatic clearance; glymphatic flow (glymphatic system)
• renal clearance

Additional terms

• drug metabolism
• pharmacokinetics
• procedural clearance