pharmacology

Question 1

function aspirin

Answer 1

inhibit coX 1 and 2

Question 2

action COX

Answer 2

synthesises PGE and thromboxane

Question 3

how does aspirin work as an antiplatelet

Answer 3

inhibits formation of thromoxane A2 -> reduces platelet ability to aggregate

Question 4

what condition is aspirin 1st line

Answer 4

IHD

Question 5

what drugs potentiate aspirin

Answer 5

hypoglycaemics, warfarin, steroids

Question 6

why should aspirin not be used in children + what exception

Answer 6

risk of reyes // except kawasaki

Question 7

why should aspirin not be used in children + what exception

Answer 7

risk of reyes // except kawasaki

Question 8

how long does aspirin need to be stopped before suregry

Answer 8

1 week

Question 9

what other drugs are the same class as clopidogrel

Answer 9

prasugrel, ticagrelor, ticlopidine

Question 10

mechanism clopidogrel and how does it inhibit platelets

Answer 10

antagonist ADP (blocks) –> reduces platelet aggregation

Question 11

when is clopidogrel used 1st line

Answer 11

following stroke // PAD

Question 12

what drugs make clopidogrel less effective

Answer 12

PPI

Question 13

2 other common antiplatelets

Answer 13

dipyramidole and abcximab

Question 14

how does unfractionated heparin work as an anticoagulant

Answer 14

inhibits thrombin, X, IX, XI, and XII

Question 15

how does LMWH anticoag

Answer 15

activates antithrombin III (and inhibits Xa)

Question 16

how is standard heparin given and what is the duration of action

Answer 16

IV, long

Question 17

how how is LMWH given and what is the duration of action

Answer 17

subcut, long

Question 18

SE heparin

Answer 18

bleeding // thrombocytopenia // osteoporosis // hyperkalaemia

Question 19

how is heparin monitored

Answer 19

standard = longer APTT // (LMWH = anti Xa)

Question 20

what is heparin induced thrombocytopenia

Answer 20

antibodies to heparin // is prothrombotic (causes more clots)

Question 21

when does heparin induced thrombocytopenia develop

Answer 21

5-10 days after treatment

Question 22

symptoms heparin induced thrombocytopenia

Answer 22

lwo platelets, thrombosis, skin allergy

Question 23

mx heparin induced thrombocytopenia

Answer 23

thrombin inhibitor eg argatroban // danaparoid

Question 24

mx heparin overdose

Answer 24

protamine sulphate (only LMWH)

Question 25

indications DOACs

Answer 25

prophlyaxis VTE after MSK surgery // stroke prevention in AF

Question 26

when are DOACs indicated for stroke prevenetion in AF

Answer 26

previous stroke, TIA, embolism // LVEF <40 // HF class II // 75 // 65 + DM, coronary heart disease, HTN

Question 27

how does dabigratan work

Answer 27

(oral) direct thrombin inhibitor (DOAC)

Question 28

contraindications dabigatran

Answer 28

reduce dose in CKD, do not prescribe if creatinine clearance <30 // recent mechanical heart valve

Question 29

mx overdose dabigatran

Answer 29

Idarucizumab

Question 30

mechanism riveroxaban, apixapan, edoxaban

Answer 30

direct Xa inhibitor

Question 31

where is apixian and edoxaban excreted

Answer 31

faecal

Question 32

riveroxaban antidote

Answer 32

Andexanet alfa*

Question 33

apixipan antidote

Answer 33

Andexanet alfa*

Question 34

what type of drug is bivalirudin

Answer 34

direct thrombin inhibitor (IV)

Question 35

mechanism fondaperinux

Answer 35

activate antithrombin III (sub cut)

Question 36

mechanism wardarin

Answer 36

inhibits vit K (1972) (IX + X, VII, II)

Question 37

indications warfarin

Answer 37

mechanical heart valve // 2nd line to DOACs

Question 38

what does the INR measure

Answer 38

patients prothrombin time : normal PT time

Question 39

SE warfarin

Answer 39

bleeding // tetarogenic (OK IN BREASTFEEDING) // skin necrosis // purple toes

Question 40

what can potientiate warfarin (generally)

Answer 40

liver disease // P450 enzyme inhibitors // cranberry juice // NSAIDs

Question 41

which drugs (P450 inducers) decrease INR and effects of warfarin

Answer 41

phenytoin, carbamezepine, phenobarbitol // rifampicin // st johns // chronic alcohol // smoking

Question 42

which drugs (P450 inhibitors) increase INR and effects of warfarin

Answer 42

cipro, clarithro, erythro, isoniazid // omeprezole // amiodarone // allopurinol // ketconazaol, fluclonazole // fluxoetine + sertraline // sodium valproate // ritonavir // acute alcohol

Question 43

mx warfarin + major bleed

Answer 43

stop // IV VitK 5mg // PT complex (or FFP)

Question 44

mx warfarin INR >8 (minor bleed)

Answer 44

stop // IV VitK 1-3mg // if still high after 24hrs give again // restart warfarin INR <5

Question 45

mx warfarin INR >8, no bleed

Answer 45

stop // VitK 1-5mg oral // repeat vitK at 24hrs if needed // restart <5

Question 46

mx warfarin INR 5-8 minor bleed

Answer 46

stop // IV vitK 1-3mg // restart when INR <5

Question 47

mx warfarin INR 5-8 no bleed

Answer 47

withhold 1-2 doses

Question 48

when might antiplatelets and anticoag be prescribed togetehr

Answer 48

CVD + AF/ DVT/ valvular disease

Question 49

mx for patients with stable CVD and AF

Answer 49

anticoag only

Question 50

platelet and coag mx post ACS (eg MI)

Answer 50

2 antiplatelets + 1 anticoag for 4-6 weeks // then 1 antiplatelet + 1 anticoag to complete 12 months

Question 51

mechanism tranexamic acid

Answer 51

binds to plasmingogen to prevent breakdown of fibrin clot

Question 52

how is tranexamic acid administered after major haemorrhage

Answer 52

IV bolus --> infusion

Question 53

what are thrombolytic drugs

Answer 53

activate plasminogen --> plasmin (break down fibrin)

Question 54

indication thrombolysis

Answer 54

stroke, PE

Question 55

examples thrombolytic drugs

Answer 55

alteplase, streptokinase, tenecteplase

Question 56

contraindications thrombolysis

Answer 56

active bleed // recent bleed // coagulation + bleeding disorders // intracranial tumour // severe hypertension // aortic dissection // stroke < 3months