Ch2 3 Pharm

• Most common method into metabolite
• Addition of oxygen or removal of hydrogen
• Enzymes on the endoplasmic reticulum

• Remove oxygen or add hydrogen
• Enzymes in the cell cytoplasm

• Original product broken down into components
• Enzymes located intra and extracellular

• Drug or metabolite coupled with an endogenous substance
• Found in the cytoplasm or on the endoplasmic reticulum

Liver

• Taking the medication for a long time alters drug metabolism
• ----Leads to faster break down and decreased effectiveness and half life
• --------Pt may need more medication, more frequently

Increased dose to produce the same effect bc of quicker break down of drug

• Kidneys
• Filtration
• Only polar drugs or metabolites excreted bc impermeable to epithelium lining
• Non-polar are reabsorbed into body bc lipophilic

nephron

inhalation

• Tissue(s)/organ(s) ability to eliminate the drug
• Based on
• ----Blood flow to the organ
• ----Portion of drug removed from the plasma as it passes through the organ
• ----dosage

• drug metabolism/excretion
• pain killers/anesthesia

Systemic clearance consists of excretion as well as biotransformation

Dependent on the organ or tissue eliminating the drug from the plasma and on the perfusion of the organ