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| When drug plasma concentration is higher than tissue concentration, the drug moves: | From plasma to tissue |
| When the drug plasma concentration is less than the tissue concentration, the drug moves: | From tissue back to plasma |
| A lipophilic drug (easily crossing the blood-brain barrier)will also likely be concentrated in this body compartment: | Fat |
| Transmembrane drug movement following filtration into the glomerular filtrate. | Ionized are charged drug species will be excreted in the urine; non-ionized, charge, drug fraction is likely reabsorbed in the renal tubules. |
| Elimination half-life: | Time required for the drug concentration to fall by 50%. |
| Drugs characterized by multicompartment pharmakokinetics and half-life: | Likely to exhibit multiple half-lives, as drug associated with each different compartment may have its own elimination half-life. |
| This drug dosing method is characterized by convenience, low expense and possibly even tolerance of dosing errors: | Oral administration |
| Absorption of acidic drugs in an acidic environment such as the stomach: | Absorption is favored |
| Absorption of a basic drug in an acidic environment such as the stomach: | Absorption is not favored because the drug will be charged in the acidic stomach environment. |
| Venous drainage from the stomach and small intestine is directed to this organ: | Liver |
| A drug extensively metabolized by first-pass hepatic pathways is least likely to be so affected if administered by which methods: | Sublingual or buccal. Venous drainage from the mouth and esophagus proceeds via the superior vena cava, not the portal system, and therefore bypasses the liver initially. |
| This drug route of administration partially bypasses the portal system: | Rectal administration, an alternative route of administration in small children or in those patients unable to tolerate oral administration. |
| Parenteral routes of drug administration include these: | Subcutaneous, intramuscular, and intravenous injection. |
| These "vessel-rich" tissues constitute only about 10% of body mass yet receive about 75% of cardiac output: | Endocrine glands, liver, kidney, heart, and brain. |
| This tissue group consists of "vessel-poor" tissues, such as: | Bone, cartilage, and ligament |
| This tissue group receives only about 6% of cardiac output: | Fat |
| About 20% of cardiac output is associated with this tissue group: | Muscle (and skin) |
| The rate of rise in drug concentration in an organism determined by: | Organ perfusion and relative drug solubility in the organ as compared to its blood solubility. |
| Equilibrium concentration of the drug in organ compared blood depends on this factor,, assuming no drug metabolism in the organ: | Relative solubility of the drug in the organ compared to its blood solubility. |
| Phase I metabolic transformation: | Characterized by conversion of the parent drug into a more polar metabolites as a result of oxidation, reduction, or hydrolytic reactions.. |
| Characteristics associated with Phase II-type metabolic biotransformation: | Phase II reactions involve association of and endogenous substrate such as glucuronic acid to either the parent drug or a phase I metabolite. The result of this reaction is a more water-soluble metabolite, more readily eliminated in the urine or feces. |
| The fraction of drug metabolized by the liver: | Extraction ratio |
| If the hepatic extraction ratio is 50%, hepatic clearance of liver blood flow: | 50% |
| Hepatic clearance is about equal to hepatic blood flow for this anesthetic agent: | Propofol |
| For drugs that exhibit low hepatic extraction ratios and are slowly cleared by the liver, the rate-llimiting step in this case is: | Metabolic capacity of the liver itself. |
| Term describing drugs with low hepatic extraction ratios: | Capacity-dependent clearance |
| Extraction ratios associated with methadone and alfentanil: | 10% and 15% respectively |
| Term describing clearance of methadone or alfentanil: | Capacity-dependent drugs |
| Renal clearance definition: | Rate of drug elimination from the body as a result of kidney excretion. |
| Renal clearance as a function of renal blood flow and renal extraction ratio: | Renal clearance = renal blood flow X renal extraction ratio. |
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