Druuugs Flashcards
What type of drug is aspirin and how does it work?
Antiplatelet drug.
Inhibits cyclo-oxygenase (platelet enzyme) irreversibly -act for lifetime of platelet (7-10 days).
What type of drug is clopiodgrel and how does it work?
Antiplatelet drug.
Blocks ADP receptor (on platelet surface) irreversibly -acts for lifetime of platelet.
What type is drug is Prasugrel and how does it work?
Antiplatelet drug.
Blocks ADP receptor irreversibly, acts for lifetime of platelet.
More rapid and consistent inhibition than clopidogrel.
What is the protocol for antiplatelet drugs & dental procedures?
Antiplatelet medications do NOT have to be stopped before primary care dental surgical procedures.
What is unfractionated heparin and when is it used?
IV anticoagulant drug, given by continuous infusion.
Binds to antithrombin and increases its activity -indirect thrombin inhibitor.
Hospital pts only.
Monitor with APTT; ratio 1.8-2.8.
What is low molecular weight heparin and when is it used?
Subcutaneous anticoagulant drug, e.g. Dalteparin.
Given once daily, no monitoring necessary.
What is the protocol for low molecular weight heparin and dental procedures?
Give last dose 24hrs before dental surgery.
Next dose 4hrs after dental surgery (as long as there’s no ongoing bleeding).
What is warfarin and how does it work?
Oral anticoagulant.
Inhibits production of Factors II, VII, IX and X, and Protein C & Protein S.
Metabolised by the liver via cytochrome.
How long does warfarin take to have effect and how long does it take for the effect to wear off?
Peak effect 3-4 days after starting.
Effect still present 4-5 days after stopping.
What can interactions with warfarin result in?
Potentiation of anticoagulation, e.g. phenytoin (reduces warfarin binding to albumin) or erythromycin (inhibits hepatic microsomal degradation of warfarin).
Inhibition of anticoagulation, e.g. carbamazepine (accelerates the hepatic microsomal degradation of warfarin) or vitamin K (enhanced synthesis of clotting factors).
How are pts takin warfarin monitored?
International Normalised Ratio (INR)
What are the side effects of warfarin?
Bleeding.
Skin necrosis.
Embryopahty.
How is warfarin reversed?
- Stop warfarin (takes 2-3days.
- Vitamin K (IV, SC or oral).
- Fresh Frozen Plasma.
- Clotting Factor Concentrate -containing factors II, VII, IX and X –> complete correction in 10mins.
What warnings should be given to pts taking warfarin?
- No IM injections.
- No aspirin or NSAID without consultation.
- No contact sports.
- Moderate alcohol intake is not harmful but XS is.
- Significant changes in diet should be reported.
- Consult doctor or pharmacist before any new meds incl OTC drugs.
What is the protocol for pts on warfarin & dental procedures?
It is safe to perform extractions on pts taking warfarin PROVIDED the INR is LESS than 4.0.
ALL pts must have INR within 24hr of extraction (or 72hr if pt stable).
