Pharm #1 - Antithrombolytics I and II Flashcards Preview

PHARM/MHD - Exam #4 > Pharm #1 - Antithrombolytics I and II > Flashcards

Flashcards in Pharm #1 - Antithrombolytics I and II Deck (42):
1

What is the mechanism of action of heparin?

How is it monitored?

Route of administration?

Complex with AT(antithrombin) and inhibits factors Xa and IIa. (thrombin)

Monitored by APTT
(2-2.5 baseline therapeutic)

IV & Subcutaneous

(oral only for warfarin)

2

What is the indication for heparin?

SURGICAL ANTI-COAGULATION! (only one indicated for this)

3

What are the adverse effects of heparin (4)
2 major

1. bleeding
2. HIT (heparin induced thrombocytopenia)
3. osteoporosis
4. alopecia

4

LMW Heparins
(branded and generic)

1. MOA

2. How is it monitored

3. Route

1.Complex with AT
inhibits factors Xa and IIa

2. monitored by anti-Xa

3. Subcutaneous

5

LMW Heparins
(Enoxaparin or Lovenox)

Indications?

Adverse effect?

Differences with heparin? (2 main, 2 others)

prophylaxis and tx. of DVT and ACS

BLEEDING


1. better bioavailability!!
2. Longer duration of action (6 hours)
3. Less bleeding
4. Less thrombocytopenia

6

What are the names of the heparin anticoagulants? (5)

Heparin antagonist?

Heparin & LMW Heparin

1. Argatroban
2. Bivalirudin
3. Hirudin
4. Fondaparinux (pentasaccharide)
5. Antithrombin Concentrate


Protamine Sulfate - heparin antagonist

7

MOA for Fondaparinux (Pentasaccharide)

Route of administration?

Indication?

Complex with AT and inhibits factor Xa

- Subcutaneous

- Management of DVT

8

Adverse effect of Fondaparinux

BLEEDING

- same for argatroban, bivalirudin, hirudin

9

What is the MOA of argatroban, bivalirudin, hirudin, and Antithrombin concentrate?

How are they all administered?

Directly inhibits IIa (thrombin - they all inhibit thrombin!)

IV!!! (same with LMW Heparins)

10

State the MOA of Argatroban

Route?

Indications?

Adverse effect?

1. inhibits IIa (thrombin)

2. IV

3. Anticoagulant
- management of HIT

4. BLEEDING

11

State the following for argatroban, bivalirudin, hirudin:

1. Route of admin
2. MOA
3. Indication
4. Adverse effect

1. Route = IV

2. MOA = inhibits IIa (thrombin)

3. Anticoagulant
- management of HIT

4. Adverse - BLEEDING

12

State the following for Antithrombin Concentrate:


1. Route of admin
2. MOA
3. Indications (4)
4. Adverse effect

1. IV

2. Inhibits IIA (thrombin)

3.
DIC
Sepsis
Thrombophilia
hypercoaguable state

4. NO ADVERSE EFFECTS

13

What drug has the following indications

DIC
Sepsis
Thrombophilia
hypercoaguable state

ANTI - THROMBIN CONCENTRATE!!!

- big gun!!

14

What is the MOA of protamine sulfate?

How is it administered?

Indication?

HEPARIN ANTAGONIST

- IV

- Reversal for heparin

15

What are the 2 major adverse effects of protamine sulfate?

1. Bradycardia
2. Hypotension

16

MOA of Warfarin (2)

- competitive antagonist of vitamin K

- suppresses the synthesis of factors 2,7,9,10

17

How is warfarin monitored?

What are the 2 indications?

1. PT/ INR

2. Prolonged treatment of DVT
3. Atrial Fibrillation

18

What are the side effects of warfarin? (3)

- bleeding
- coumadin induced necrosis
- INTERACTION WITH SEVERAL MEDICATIONS (since it is highly protein bound) which results in bleeding due to the potentiating effect of warfarin

19

MOA of vitamin K

monitoring?

- Cofactor in the synthesis of functional forms of factors:

2, 7, 9 , 10

(inhibited by warfarin)

2. monitoring NOT REQUIRED

20

What are the indications of vitamin K?

1. Hypoprothrombinemia

2. Intestinal disorders

3. Gastrectomy

4. reverses the effects of WARFARIN

- which is why patients are advised NOT to eat green leafy vegetables

21

What is the main side effect of Vitamin K

Hemolysis

22

Oral Anti-Xa

What are the 3 drugs in this category?

1. Rivaroxaban
2. Apixaban
3. Edoxaban

- all 3 have "exo & all inhibit Xa!!'

23

What is the MOA of

1. Rivaroxaban
2. Apixaban
3. Edoxaban

Inhibits factos Xa

24

For what is monitoring not required? (because there is no available monitoring)

1. Vitamin K

2. Rivaroxaban
3. Apixaban
4. Edoxaban

25

What are the Indication for the Oral Anti-Xa agents?

1. Rivaroxaban
2. Apixaban
3. Edoxaban

What is Rivaroxaban approved for?

Stroke prevention in patients with AF

Ravaroxaban also approved for prophylaxis and tx. of DVT

26

What is are the 2 major adverse effects of Oral Anti-Xa agents?

1. Rivaroxaban
2. Apixaban
3. Edoxaban

1. Bleeding

2. Liver toxicity!

(same as Dabigatran - oral anti-thrombin)

27

What is the MOA of Dabigatran?

Inhibits thrombin (IIa)

28

How is Dabigatran monitored?

It is NOT monitored!
- no tests for Dabigtran

29

What is the major indication for Dabigatran (Oral antithrombin)

Stroke prevention in patients with AF

30

What are the major side effects of Dabigatran? (2)

Bleeding

Liver toxicity

31

Which drug has a duration of 1-2 hours and a half life that is dose dependent with a RAPID onset?

HEPARIN

32

How is heparin metabolized?

What has better bioavailability, heparin or LMW Heparins?


Which is used for surgical anticoagulation (warfarin/hep); which is used for CHRONIC anticoagulation?

Metabolized by the LIVER, some by kidney (20-25%)

- some picked up by mast cells

2. Low molecular weight heparins! - when given subcutaneously

DOSED IN MG , not units like HEPARIN!

3. Surgical: heparin (no oral!)
Chronic anticoagulation = warfarin (at war with your body!)

33

Which drug is contraindicated in pregnant women?

WARFARIN

- can cross placenta and cause bone & bleeding problems

- All oral anticoagulants pass the placental barrier and may cause fetal bone malformation.

34

What is hirudin used for?

What is the commercial recombinant preparation called?

Direct Thrombin Inhibitor (DTI) used in patients that are heparin compromised


hirudin keeps the blood flowing and prevents clots from forming!

2. REFLUDAN
- used for anti-coagulant management for HIT patients

35

What are the main factors that effect warfarin dose?

1. DIET - vitamin K can increase clotting - green leafy veggies (warfarin inhibits vitamin K synthesis)

2. LIVER - disease can result in a lower production of coagulation factors

3. DRUGS - aspirin is highly protein bound and can displace warfarin resulting in an increased INR and more anti-coagulation

36

What is the principal toxicity of warfarin?

hypoprothrombinemia

ecchymosis, purpura, hematuria, hemorrhage.

37

What is coumadin skin necrosis?

the impairment of the functionality of protein C


- This protein also requires gamma-carboxylation of glutamic acid for functionality (vitamin K dep)

Protein C normally acts as an anti-coagulant by interacting with factors 5 and 8
inhibits their activation!

Takes 48 hours before factor 7 begins to decrease after warfarin, but prior to this PROTEIN C decreases!!!!!
- cannot act as an anti-coagulant by inhibiting factor 5 and 8 so acts as an additional phenomenon causing the blood to CLOT
may result in HEMORRHAGIC LESIONS!

38

What is the tx for coumadin skin necrosis/ oral anti-coagulant overdose?

1. Infuse factors 2,7,9,10 by giving fresh blood or frozen plasma

2. Recombinant factor 7a

3. Vitamin K

39

Rivaroxaban and Apixaban, Edoxaban are cleared how?


Which has less plasma protein binding than the rest?

1. R - RENALLY (65%)

2. Apixaban = 25%

3. Edoxaban - 35% renal (rest of drugs are LIVER)

- are oral Anti-10a agents

4. EDOXABAN

do not need to monitor if on these drugs BUT there is no test to monitor them!!!

40

What is an anti-thrombin agent?

How is it eliminated?

DABIGATRAN

- RENAL elimination!!!! 100%

41

What type of drugs are
Enoxaparin or Lovenox

LMW Heparins

42

What is the difference between heparin and LMW heparin in terms of elimination kinetics?

Heparin is dose dependent

LMW hep is dose independent and has a longer half life