Flashcards
Pharmacology
Cards in this deck (36)
- 1BioavailabilityPercent of unchanged drug that reaches circulation
- 2Which drugs go through first-pass hepatic metabolism?Propanolol and lidocaine
- 3What do a drug need to be soluble?Be largely hydrophobic with some aquous solubility / Be a weak acid or weak base / Be highly lipid-soluble transported by albumin.
- 4When are two drugs bioequivalent?When they have the same bioavailability
- 5When do two drugs have therapeutic equivalence?When they have the same efficacy and safety.
- 6What variables affect bioequivalence?Drug concentration and time to peak.
- 7How is drug distribution given?Drug goes from plasma to interstitium and cell.
- 8What happens when free drug decreases?The bounds dissociate in order to mantain free drug concentration constant.
- 9Plasma Vd-Large molecular weight/protein bound drugs.
-6% BW, 4L
-Heparin - 10Extracellular Vd-LMW and hydrophilic drugs
-Stay in ECF
-20%BW, 14 L
-Aminoglycosides - 11Total body water Vd-LMW and hydropobic drugs
-Enters cell
-60% BW, 42L
-Ethanol - 12What happens to Vd during pregnancy?Vd increases during pregnancy
- 13Drug with extremely high volume distributionThiopental
- 14Volume distribution formulaVd=
amount of drug/
desired plasma concentration - 15Serum drug distribution phases-Rapid distribution
-Slow elimination phase - 16Rapid distribution phaseInitial decrease in plasma
Drug is transfered to extravascular fluids - 17Slow elimination phaseExcretion or biotransformation of the drug
- 18What happens if Vd increase?1. Drug in extravascular space increase
2. Pass by excretory organs decrease
3. Half life increase
4. Duration of action increase - 19What is the difference between bound and free drug?Bound drug is inactive. Free drug has action and eliminates.
- 20Is a medical condition in which free drug highly increasesHypoalbuminemia
- 21Class I binding drugsThere is more albumin than drug.
Warfarin - 22Class II binding drugsMore drug than albumin. Displaces class I drugs.
Sulfonamides. - 23What are the characteristics of drugs with albumin affinity?They are weak acids, hydrophobic and can be absorbed orally.
- 24What are the conditions that can lead to drug displacement and increase free drug?Low Vd and low therapeutic index
- 25MetabolismConverts lipophilic drugs in polar excretable drugs.
It happens in liver (major), kidney and intestines. - 26First-order metabolism-Low doses
-Dose proportional rate
-Enzyme catalized
-Fraction eliminated per time
-Mikaelis-Menten kinetics
-Most common elimination rate
-Exponential relationship with time - 27Zero-order metabolism-High dose
-Amount eliminated per time
-Dose independent
-Linear relationship with time
-Phenytoin, aspirin, ethanol. - 28Half-life formulat1/2=
0.693 x Vd/
CL - 29Conditions that prolong half-life-decrease in renal/hepatic fllow (cardiogenic shock, HF, hemorrhage)
-renal disease
-decreased metabolism (drug inhibition, hepatic insufficiency)
-enterohepatic circulation reabsorption - 30Conditions that shorten half-life-increased hepatic flow
-decreased protein binding
-increased metabolism - 31Pharmacokineticschanges of plasma drug concentration and drug amount in te body
- 32When is steady state achieved?when the rate of infusion = rate of elimination
- 33Elimination rate formula= CL x plasma concentration
- 34steady-state/washout tresholds1t - 50%
2t- 75%
3.3t - 90%
4-5t - 100% - 35What happens with plasma concentration in oral administration?plasma concentration is influenced by absorption and drug elimination rate.
- 36How are half-life and steady-state affected by dose?half-life is not affected by dose change. ss is not affected by multiple or frequent doses.
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- Flashcards on Pharmacology, created by DoctorMommy on 05/03/2015.
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- DoctorMommy
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