Drug mechs Flashcards
Cyclosporine A
Calcineurin inhibitor
Signal 1
Calcineurin usually activates NFAT whcih is a TF needed for expression of CK like IL-2, IL-4
Explain the AZA metabolism issues
AZA metabolised to 6MP, which is also active
Works by inhibiting A,G synthesis (purine).
TPMP metabolises to the good guys 6MMPR and 6MMP-if not enough then shunted into the 6-TGN pathway which is toxic to bone marrow.
Xanthine oxidase also eliminates 6-MP into 6-thiouric acid, so allopurinol increases 6-MP levels
MOA amiodarone
K channel blocker–>inhibit repolarisation and prolong action potential
QT prolonging
also sodium channel block
Difference between elimination and clearance
elimination is where drug is metabolised into different chemical compound or cleared unchanged
Clearance is efficiency of elimination of blood from the systemic circulation irreversibly
major determinant of vol of dist is
protein binding
Absorption of drug is
how much intact drug gets to PORTAL circulation
Bioavailability is
amount of drug that reaches systemic circulation as an intact drug
metformin does what to B12?
reduces absorption but probably not clinically significant
What is the difference between risk of myopathy with different statins?
More likely with lipophilic- atorvastatin, simvastatin
Than hydrophilic - rosuva, fluva, prava
beta blocker overdose?
atropine and glucagon
Cocaine MOA and what do you give them?
block serotonin, NO, dopamine uptake
avoid beta blockers as unopposed blockade can lead to alpha receptor induced coronary vasospasm
benzos first line.
Do you get fever with aspirin overdose?
Yes
wWhich drugs can be cleared by dialysis
BLAST
barbituate lithium alcohol salicylate theophylline
not dig, TCA, beta blocker
break through dose is what proportion of daily dose?
1/6
What happens if you give verapamil with loperamide
P glycoprotein inhibited by verapamil so loperamide can cross BBB and cause respiratory depression