Drug Excretion Lecture Notes PDF

9/10/2024 Drug Excretion Fadi Khasawneh, Ph.D. (361) 221-0755 [email protected] 1 Learning Outcomes 1. Define drug excretion 2. List the various types of drug elimination. 3. Describe drug filt...

9/10/2024 Drug Excretion Fadi Khasawneh, Ph.D. (361) 221-0755 [email protected] 1 Learning Outcomes 1. Define drug excretion 2. List the various types of drug elimination. 3. Describe drug filtration, active tubular secretion, reabsorption. 4. List other means of drug excretion. 2 1  9/10/2024 What is Excretion? Excretion is defined as a process whereby drugs or metabolites are irreversibly transferred from internal to external environment through renal or non renal route. 3 Types of Elimination Three types of elimination – Cellular ABC transporters – P-glycoprotein/MDR1 (multidrug resistance protein 1) – Renal ~25% of blood flows through the kidney, so many drugs are excreted in the urine – Hepatic Some drugs are transported into the bile from the liver and thus enter the duodenum and are either excreted in the feces or are re-absorbed and create a cycle 4 2  9/10/2024 Renal 1. Plasma is filtered through a sieve and most molecules enter the filtrate (including all sugars; drug filtration; glomerular filtration) 2. ABC transporters mediate drug secretion to the filtrate (active tubular secretion) 3. Some drugs are reabsorbed (passive back-diffusion; drug reabsorption) 4. Drugs left in the filtrate make their way to the bladder and are urinated out of the body 5 Other Means of Drug Excretion? 1. Biliary 2. Milk 3. Pulmonary 6 3  9/10/2024 Any questions? The End 7 4