Pharmacology 2060A/B Lecture Notes - Lecture 3: Body Water, Extracellular Fluid, Adipose Tissue
Document Summary
Drugs distribute into compartments in the body where they may be stored, metabolized, excreted or exert their pharmacological effect. Interstitial space the extracellular fluid that surrounds cells. Low molecular weight, water soluble drugs distribute in the interstitial space. Total body water includes the fluid in the interstitial space, intracellular fluid and the plasma. Plasma the non-cell containing component of blood. Drugs strongly bound to plasma protein and high molecular weight drugs that are unable to move through capillary fenestrations typically distribute in plasma. Lipid soluble (lipophilic) drugs distribute into adipose tissue. Muscle some drugs bind tightly to muscle tissue. Bones some drugs adsorb onto the crystal surface of bone with eventual incorporation into the crystal lattice. Bone can be a reservoir for the slow release of some drugs. Drug distribution is determined by: blood flow to tissues, ability of drug to move out of capillaries, ability of drug to move into cells.