Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
WEEK 5:
ADME 2
| Question | Answer |
|---|---|
| pharmacokinetics | what body does to drug (ADME) |
| ADME | administration, distribution, metabolism, excretion/ elimination |
| ADME meaning | absorption, distribution, metabolism, excretion/elimination |
| TDM | therapeutic drug monitoring |
| first order kinetics | body removes constant proportion of drug per unit time |
| zero order kinetics | body removes constant amount of drug per unit time |
| IV injection | drug injected directly into bloodstream so entire dose is available- one compartment model |
| one compartment model | drug distributes instantly throughout entire body |
| first pass metabolism | drug metabolised in liver before it enters systemic circulation |
| IV bioavailability + characteristics | 100%, most rapid onset |
| IM bioavailability + characteristics | 75 to ≤ 100%, large volume but painful |
| subcutaneous bioavailability + characteristics | 75 to ≤ 100%, smaller volume than IM |
| oral bioavailability + characteristics | 5 to ≤ 100%, convenient + significant first pass effect |
| rectal bioavailability + characteristics | 30 to ≤ 100%, less 1st pass effect than oral |
| inhalation bioavailability + characteristics | 5 to ≤ 100%, often very rapid onset |
| transdermal bioavailability + characteristics | 80 to ≤ 100%, slow absorption, lacks first pass effect |
| AUC | area under the curve - plot of drug concentration in blood plasma over time |
| describe the AUC for oral dose | slope |
| describe the AUC for IV dose | diagonal line going down |
| bioavailability | F ( fraction absorbed) = AUC oral / AUC IV |
| digoxin elixir F | 0.8 |
| digoxin tablets F | 0.7 |
| digoxin gelatine capsules F | 1 |
| formula for dose given | amount needed / F |
| salt factor definition | proportion of medicine which is active drug |
| salt factor formula | dose of active (free) drug/ amount (dose of salt form medicine) |
| formula for amount of drug | S x F x dose |
| Vd in words | volume of distribution |
| Vd definition | volume drug is dissolved in body between tissues and plasma proteins |
| formula for Vd | amount in body (dose) / plasma concentration at time 0 (t0 conc) |
| small Vd | drug only goes to one part of the body |
| large Vd | drug goes to many parts of the body |
| chloroquine | drug with a Vd > 100 L/kg (high Vd) |
| chloroquine side effects in heart (CVS) | ECG changes, cardiomyopathy |
| chloroquine side effects in eyes | retinopathy and blurred vision |
| chloroquine side effects in CNS | headache, delirium and seizure |
| chloroquine side effects in nerves | nerve deafness, reduced hearing |
| chloroquine side effects in neuromuscular + skeletal | neuromyopathy |
| chloroquine side effects in lungs | respiratory arrest |
| range for drugs with large Vd | >5-10 L/kg |
| range for drugs with small Vd | <1 L/kg |
| examples of drugs with a large Vd | antidepressants, propranolol, verapamil |
| examples of drugs with small Vd | theophylline, phenytoin, lithium, phenobarbital |
| graph of Vd after IV administration | diagonal line down - extrapolate to t=0 gives plasma concentration at t=0 |
| units for Vd | L or L/kg |
| digoxin Vd | 7.3 L per kg (511 L) |
| CL in words | clearance |
| CL meaning | how blood removes drug from blood plasma in mL/min or L/h |
| CL renal | rate elimination (kidney) / concentration |
| CL liver | rate elimination (liver) / concentration |
| CL other | rate elimination (other) / concentration |
| CL systemic meaning | how blood removes drug from blood plasma in whole body |
| CL systemic formula | CL renal + CL liver + CL other |
| exponential decay graph | exponential slope downwards showing gradual clearance of drug concentration over time split into distribution phase + elimination phase |
| formula for first order kinetics | Ct = C0e^-kt |
| what does Ct mean in the formula for first order kinetics | drug concentration in plasma at time t |
| what does C0 mean in the formula for first order kinetics | initial drug concentration at time 0 |
| what does e mean in the formula for first order kinetics | 2.718 |
| what does k mean in the formula for first order kinetics | rate constant (per minute/hour) |
| what does t mean in the formula for first order kinetics | time |
| formula for rate constant | k= CL / Vd |
| formula for CL using rate constant (K) | CL = k x Vd |
| what is T(1/2) | time taken for the concentration of drug to decrease by 50% |
| -kt value? | ln 0.5 (-0.693) |
| half life formula | 0.693/ k |
| phenytoin onset of action | 0.5-1 hour |
| phenytoin time of peak | 2-3 hours |
| phentytoin Vd | 0.6-0.7 L/kg |
| phenytoin t(1/2) half life | 22 hours |
| phenytoin bioavailability and clearance | variable |
| phenytoin therapeutic plasma concentration | 10-20 ug/mL |
| at what level is there decreased mentation (mental activity) for phenytoin | >40 ug/mL |
| at what level is there death for phenytoin | >100 ug/mL |
| at >40ug/mL of phenytoin what side effect is possible | decreased mentation (mental activity) |
| at >100ug/mL of phenytoin what side effect is possible | death |
Created by:
kablooey
Popular Pharmacology sets