Term
| WHERE ARE DRUGS EXCRETED FROM? (8 ANSWERS) |
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Definition
| PRIMARILY URINE, BUT CAN BE BILE, SWEAT, SALIVA, TEARS, FECES, BREAST MILK, OR EXHALATION |
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Term
| HOW CAN DRUGS BE EXCRETED IN RELATION TO COMPOSITION? CHANGED, UNCHANGED, OR BOTH? |
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Definition
| DRUGS CAN BE EXCRETED UNCHANGED (SAME COMPOUND AS PARENT DRUG), OR AS A METABOLITE |
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Term
| DRUGS LIKE OTHER SUBSTANCES UNDERGO WHAT? WHAT IS THE FORMULA? |
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Definition
| UNDERGO FILTRATION, SECRETION, AND REABSORPTION. AMOUNT OF DRUG EXCRETED = (FILTERED + SECRETED) - REABSORBED. |
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Term
| WHAT IS THE FIRST STEP IN DRUG SECRETION? IT VARIES BASED ON WHAT 2 THINGS? |
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Definition
| FILTRATION IS THE FIRST STEP IN DRUG EXCRETION. IT VARIES BASED ON GFR (NML=125ML/MIN) AND PROTEIN BINDING. |
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Term
| WHAT IS INDEPENDENT OF THE PLASMA CONCENTRATION OF A DRUG? |
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Definition
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Term
| WHAT KIND OF DRUGS ARE NOT FILTERED AND WHY? |
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Definition
| DRUGS THAT ARE BOUND TO PLASMA PROTEINS ARE NOT FILTERED BECAUSE THE PROTEINS DO NOT PASS THROUGH THE GLOMERULI. * ALTHOUGH ** PROTEIN BOUND DRUGS MAY BE CLEARED VIA SECRETION BECAUSE THE TIME IT TAKES FOR TUBULAR TRANSPORT IS LONG ENOUGH TO ALLOW FOR PROTEIN DISSOCIATION. |
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Term
| WHAT TYPE OF TRANSPORT DOES SECRETION INVOLVE AND WHY? |
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Definition
| SECRETION INVOLVES ACTIVE TRANSPORT SO THE TRANSPORT MOLECULES CAN BECOME FULLY SATURATED. * THEIR ARE A LIMITED NUMBER OF TRANSPORT MOLECULES. |
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Term
| DESCRIBE THE PROCESS OF REABSORPTION. |
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Definition
| IT CARRIES THE PREVIOUSLY FILTERED OR SECRETED DRUG BACK IN TO THE PLASMA. IT CAN BE ACTIVE OR PASSIVE. |
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Term
| HOW CAN DRUGS BE REABOSRBED ONCE THEY ARE IN THE URINE? |
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Definition
| THE DRUGS MUST BE HIGHLY LIPID SOLUBLE OR LARGE UNIONIZED FRACTION AT URINE pH (4-8). THE DRUG HAS BEEN FILITERED OR SECRETED INTO THE URINE, SO IF THE DRUG IS UNIONIZED AT THAT pH, IT CAN FREELY CROSS BACK OVER INTO THE PLASMA. |
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Term
| WHAT INCREASES BILIARY EXCRETION. |
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Definition
| BILIARY EXCRETION IS INCREASED BY GLUCURONIDATION. GLUCURONIDATION IS THE ADDITION OF GLUCURONIC ACID TO A SUBSTRATE. |
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Term
| DESCRIBE EXTRAHEPATIC CYCLING. |
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Definition
| AFTER BILE EMPTIES INTO THE INTESTINE, SOME DRUGS MAY BE REABSORBED BACK INTO THE CIRCULATION, INCREASING THE PLASMA LEVEL OF THE COMPOUND. THIS CAN ACCOUNT FOR A DECREASED ELIMINATION RATE AND PROLONGED HALF-LIFE OF THE DRUG. |
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Term
| WHAT DOES QUANTITATIVE PHARMACOKINETICS ALLOW US TO BE ABLE TO DO? |
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Definition
| IT ALLOWS USE TO MEASURE THE CONCENTRATIONS OF DRUGS. |
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Term
| HOW MANY COMPARTMENT MODELS ARE THERE AND WHAT ARE THEIR NAMES? |
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Definition
| 2. ONE COMPARTMENT MODEL AND TWO COMPARTMENT MODEL. |
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Term
| DESCRIBE THE ONE COMPARTMENT MODEL. |
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Definition
| IT IS SIMPLE BUT UNREALISTIC. THE DRUG IS ABSORBED INTO THE BLOOD AND ELIMINATED FROM THE BODY, BOTH AT A CONSTANT RATE. |
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Term
| DESCRIBE THE TWO COMPARTMENT MODEL. |
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Definition
| THIS IS A MORE ACCURATE REPRESENTATION OF PHARMACOKINETICS.*** THE DRUGS ARE ABSORBED INTO THE CENTRAL COMPARTMENT (BLOOD), DISTRIBUTED INTO A PERIPHERAL COMPARTMENT (TISSUES), AND ELIMINATED FROM CENTRAL COMPARTMENT. THE CONCENTRATION RISES QUICKLY THEN SLOWLY DECLINES. |
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Term
| SUMMARIZE THE GRAPH ON PAGE 15 CONCERNING BLOOD, VRG, MUSCLE, AND ADIPOSE TISSUE IN RELATION TO TIME AND FRACTION OF DOSE IN COMPARTMENT. |
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Definition
| THE BLOOD IS THE FIRST COMPARTMENT THAT THE DRUG GOES INTO ALTHOUGH IT SOON IS TRANSFERRED TO VRG WHEN AT THE SAME TIME IT IS TRANSFERRED TO MUSCLE AND ADIPOSE TISSUE. THE MUSCLE AND ADIPOSE TISSUE RETAINS A HIGHER FRACTION OF DOSE IN COMPARTMENTS FOR A LONGER TIME THAN THE BLOOD OR VRG. THE ADIPOSE TISSUE RETAINS THE FRACTION OF DOSE THE LONGEST. |
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Term
| WHAT IS A PLASMA CONCENTRATION CURVE? |
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Definition
| IT SHOWS THE CONCENTRATION OF A DRUG IN THE PLASMA OVER A PERIOD OF TIME. |
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Term
| DESCRIBE CMAX, TMAX, AND MEC. |
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Definition
| Cmax IS THE MAXIMUM CONCENTRATION. IT IS THE PEAK OF THE CURVE. THE Tmax IS THE TIME NEEDED TO REACH MAXIMUM CONCENTRATION. THE MEC IS THE MINIMUM EFFECTIVE CONCENTRATION. ANOTHER TERM IS THE DURATION OF ACTION. |
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Term
| WHAT IS BIOAVAILABILITY? WHAT IS THE FORMULA? |
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Definition
| THE FRACTION (F) OF THE ADMINISTERED DRUG THAT REACHES THE SYSTEMIC CIRCULATION IN ACTIVE FORM. THE ****BIOAVAILABILITY = AUC ORAL/AUC IV.**** |
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Term
| WHAT FACTORS CAN AFFECT THE BIOAVAILABILITY OF ORALLY ADMINISTERED DRUGS? 5 ANSWERS. |
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Definition
| ABSORPTION OF FOOD, GASTRIC ACID INACTIVATION, RAPID METABOLIZATION, FIRST-PASS HEPATIC EFFECT, AND LIPID SOLUBILITY. |
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Term
| WHEN ARE PLASMA LEVELS OF A DRUG AT THEIR PEAK? |
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Definition
| IMMEDIATELY AFTER INJECTION |
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Term
| WHAT IS THE PHASE CALLED IN WHICH PLASMA LEVELS DROP RAPIDLY? WHAT CHANGES THE SLOPE OF THE CURVE? |
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Definition
| A PHASE OR ALPHA PHASE. AS LIPID SOLUBILITY INCREASES, SO DOES THE SLOPE OF THE A PHASE OF THE CURVE. |
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Term
| WHAT PART OF THE PHASE EXHIBITS A SLOWER PLASMA CONCENTRATION DECLINE? |
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Definition
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Term
| KNOWING THE PLASMA CONCENTRATION OF A DRUG AFTER THE DISTRIBUTION PHASE CAN HELP US DETERMINE WHAT? |
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Definition
| HOW MUCH OF THE DRUG WAS DELIVERED TO TARGET SITES. |
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Term
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Definition
| WHEN WE EXTRAPOLATE THE SLOPE OF THE ELIMINATION CURVE BACKWAORS IT GIVES US THE CONCENTRATION AT TIME ZERO. |
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Term
| WHAT IS THE DEFINITION OF VOLUME OF DISTRIBUTION (Vd)? |
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Definition
| A THEORETICAL VOLUME SHOWING HOW DRUGS ARE DISTRIBUTED IN THE BODY. |
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Term
| WHAT DO WE COMPARE THE AMOUNT OF DRUG GIVEN TO AND WHY IN RELATION TO Vd? WHAT IS THE EQUATION? |
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Definition
| SINCE WE ARE TYPICALY CONCERNED WITH THE PLASMA CONCENTRATION OF THE DRUG, WE COMPARE THE AMOUNT OF DRUG GIVEN, WITH THE PLASMA CONCENTRATION. Vd= DOSE GIVEN/CONCENTRATION IN PLASMA |
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Term
| WHAT CAN GIVE US AN APPROXIMATION OF HOW MUCH OF THE DRUG IS RAPIDLY DISTRIBUTED TO TISSUE SITES? |
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Definition
| THE DOSE GIVEN CAN ALSO BE THOUGHT OF A THE TOTAL AMOUNT OF DRUG IN THE BODY, SO COMPARING THAT TO THE PLASMA CONCENTRATION CAN GIVE US AN APPROXIMATION OF HOW MUCH OF THE DRUG IS RAPIDLY DISTRIBUTED TO TISSUE SITES (PROTEIN-BOUND DRUG IS INCLUDED IN A PLASMA CONCENTRATION). |
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Term
| WHAT SIZE OF VOLUME OF DISTRIBUTION ARE RELATIVELY CONTAINED IN THE PLASMA? |
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Definition
| DRUGS WITH A SMALL VOLUME OF DISTRIBUTION. |
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Term
| WHAT SIZE OF VOLUME OF DISTIBUTION ARE MORE RAPIDLY DISTRIBUTED AND STRONGLY BOUND TO TISSUE SITES? |
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Definition
| LARGE VOLUME OF DISTRIBUTION |
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Term
| WHAT DOES IT MEAN WHEN THE Vd LEVELS AROUND 3-5 LITERS? |
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Definition
| IF THE Vd IS CLOSE TO THE TOTAL VOLUME OF WATER IN THE PLASMA, THEN A DRUG IS MAINLY RESTRICTED TO THE PLASMA. |
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Term
| WHAT DOES IT MEAN WHEN THE Vd LEVELS ARE AROUND 40-45 LITERS? |
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Definition
| IF THE Vd IS CLOSER TO THE TOTAL BODY WATER VOLUME, THEN THE DRUG HAS REACHED INTRACELLULAR FLUID. |
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Term
| WHAT DOES IS MEAN WHEN A Vd IS GREATER THAN OF WATER IN THE PLASMA OF TOTAL BODY WATER? |
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Definition
| A Vd GREATER THAN THESE PHYSIOLOGIC MEASUREMENTS TYPICALLY MEANS THAT THE DRUG HAS REACHED FATTY TISSUE OR HAVE UNDERGONE SIGNIFICANT ION TRAPPING IN THE INTRACELLULAR FLUID COMPARTMENT. |
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Term
| WHEN DOES REDISTRIBUTION OCCUR? |
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Definition
| ONCE ELIMINATION OF A DRUG BEGINS AND THE PLASMA CONCENTRATIONS BEGINS TO FALL, DRUGS LEAVE THE SITES OF DISTRIBUTION IN ORDER TO MAINTAIN AN EQUILIBRIUM (FOLLOWING A CONCENTRATION GRADIENT). |
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Term
| DOES REDISTRIBUTION ACCOUNT FOR A SLOW OR RAPID FALL IN PLASMA CONCENTRATION? |
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Definition
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Term
| WHY IS REDISTRIBUTION IMPORTANT IN RELATION TO ANESTHETIC INDUCTION AGENTS? |
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Definition
| WHEN PLASMA CONCENTRATIONS BEGIN T FALL DUE TO DISTRIBUTION TO THER VESSEL RICH GROUP AND RAPID ELIMINATION, REDISTRIBUTION BACK TO THE PLASMA CAUSES A FALL IN CONCENTRATIONS AT THE BRAIN (TARGET SITE) AND ALLOWS THE PATIENT TO WAKE UP. |
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Term
| WHAT IS THE MAIN CALCULATION FOR DRUG ELIMINATION FROM THE BODY? |
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Definition
| CLEARANCE (Cl). THIS TERM IS USED INTERCHANGEABLY WITH BOTH METABOLISM (CLEARANCE OF A PARENT DRUG FROM THE PLASMA) AND EXCRETION (CLEARANCE OF THE METABOLITES FROM THE BODY). Cl = THE *VOLUME* OF BLOOD (L) THAT CAN BE CLEARED OF DRUG PER UNIT TIME. |
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Term
| WHAT IS A SIMPLE FORMULA FOR Cl? |
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Definition
| Cl (TOTAL) = Cl RENAL + Cl HEPATIC + Cl OTHER... |
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Term
| EACH DRUG HAS A CONSTANT VOLUME OF CLEARANCE, BUT THE AMOUNT OF THE DRUG CLEARED WILL VARY DEPENDING ON WHAT? |
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Definition
| PLASMA CONCENTRATION AND PROTEIN BINDING |
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Term
| DESCRIBE FIRST-ORDER KINETICS. |
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Definition
| THE AMOUNT OF DRUG ELIMINATED FROM THE BODY IS PROPORTIONAL TO THE PLASMA CONCENTRATION OF A DRUG. MOST DRUGS FOLLOW THIS PRINCIPLE. AS THE CONCENTRATION OF THE DRUG DECLINE, SO DOES THE AMOUNT ELIMINATED PER HOUR. |
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Term
| DESCRIBE ZERO-ORDER KINETICS. |
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Definition
| THE RATE OF DRUG ELIMINATION IS CONSTANT, AND IS NOT RELATED TO THE PLASMA CONCENTRATION. A CONSTANT AMOUNT OF DRUG ELIMINATED PER UNTIL TIME. |
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Term
| WHICH ORDER OF KINETICS TAKE PLACE WHEN THE BODY'S NORMAL ELIMINATION PROCESSES ARE IMPAIRED (LIVER OR KIDNEY DISEASE)? |
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Definition
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Term
| NAME THE FEW DRUGS THAT FOLLOW ZERO-ORDER KINETICS? |
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Definition
| ASA, ETHANOL, AND DILANTIN. THESE ARE TYPICALLY ONLY WHEN A DRUG HAS SATURATED THE ELIMINATION PROCESS. |
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Term
| WHAT IS THE ELIMINATION HALF-LIFE (t1/2)? |
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Definition
| THE TIME REQUIRED TO REDUCE THE PLASMA CONCENTATION BY 50% IS THE ELIMINATION HALF-LIFE. |
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Term
| WHAT INFLUENCES THE t1/2? |
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Definition
| HOW MUCH OF THE DRUG IS FREE IN THE PLASMA (Vd AND PROTEIN BINDING) AND THE RATE OF CLEARANCE. |
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Term
| WHAT IS THE FORMULA FOR t1/2? |
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Definition
| t1/2=0.693 Vd/Cl OR Cl=0.693 Vd/t1/2 |
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Term
| HOW MANY HALF-LIVES DOES IT TAKE TO REMOVE A DRUG FROM THE BODY? |
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Definition
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Term
| WHAT IS t1/2 INVERSELY PROPORTIONAL TO AND DIRECTLY PROPORTIONAL TO? |
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Definition
| t1/2 IS INVERSELY PROPORTIONAL TO CLEARANCE AND DIRECTLY PROPORTIONAL TO VOLUME OF DISTRIBUTION |
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Term
| WHAT IS THE GOAL WITH PHARMACOLOGIC INTERVENTION? |
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Definition
| TYPICALLY TO ESTABLISH A STEADY PLASMA CONCENTRATION OF A DRUG. |
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Term
| WHEN IS THE STEADY STATE CONCENTRATION (Css) IN EQUILIBRIUM? |
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Definition
| WHEN THE INPUT AND CLEARANCE OF A DRUG ARE APPROXIMATELY EQUAL (AKA: TARGET CONCENTRATION |
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Term
| WHAT TYPE OF ORDER PROCESS IS Css? |
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Definition
| A FIRST-ORDER PROCESS, SO JUST AS IT TAKE APROXIMATELY 5 HALF LIVES TO CLEAR A DRUG, IT TAKES APPROXIMATELY 5 HALF LIVES TO REACH A STEADY STATE CONCENTRATION OF A DRUG. |
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Term
| IN RELATION TO MULTIPLE DOSING WHAT CAN DETERMINE THE PLASMA CONCENTRATION? |
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Definition
| THE DOSE AND TIME INTERVAL BETWEEN DOSES. |
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Term
| HOW CAN A STEADY STATE CONCENTRATION Css BE REACHED IN A REASONABLE AMOUNT OF TIME? |
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Definition
| THE DOSING INTERVAL SHOULD BE SHORT ENOUGH TO ALLOW DRUG ACCUMULATION. |
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Term
| IN RELATION TO CONTINUOUS DOSING, REGARDLESS OF THE INFUSION RATE, THE STEADY STATE PLASMA CONCENTRATION IS ONLY REACHED AFTER HOW MANY HALF-LIVES? |
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Definition
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Term
| WHAT WILL HAPPEN TO A DRUG WITH A SHORT HALF-LIFE? |
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Definition
| IT WILL REACH A STEADY STATE CONCENTRATION QUICKLY AND VICE VERSA. |
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Term
| WHAT IS A CONTEXT-SENSITIVE HALF-TIME? |
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Definition
| IT CALCULATES THE TIME NECESSARY FOR PLASMA CONCENTRATION TO FALL BY HALF AFTER DISCONTINUING A CONTINUOUS DRUG INFUSION. |
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Term
| DESCIBE WHAT HAPPENS IN A CONTINUOUS INFUSION. |
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Definition
| ACCUMULATION OF THE DRUG IN THE PERIPHERAL COMPARTMENTS WILL OCCUR WHEN THE INFUSION IS DISCONTINUED AND PLASMA CONCENTRATIONS BEGINS TO FALL, THE DRUG IN THE PERIPHERAL COMPARTMENT WILL FOLLOW THE CONCENTRATION GRADIENT AND RETURN TO THE PLASMA. |
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