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Flashcards in Aspirin (ASA) Deck (23)
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1

What is the most self-prescribed medicine on the market?

Aspirin

2

What is the chemical name for aspirin?

acetylsalicylic acid (ASA)

-Acetic acid (HA) and salicylic acid (SA)

3

What are most of aspirin's effects due to?

Inhibition of prostaglandin synthesis

4

Aspirin is more effective against _______ pain (caused by _________) versus ________ pain (direct irritation of nerve endings).

  • throbbing
  • inflammation
  • stabbing

5

What are the pharmacokinetics of aspirin?

Rapidly and completely absorbed from stomach and small intestine, producing peak effect on empty stomach in 30 minutes

Hydrolyzed to salicylate in GI tract and via first pass effect in liver

6

How does the half-life work with aspirin?

It is dose-dependent,

With small doses - half life - 2-3 hours

With larger doses - a half-life of 15-30 hours can be attained

It can lead to Zero-order kinetics - poisoning

7

What are the effects of aspirin?

  • Analgesic - relieves mild to moderate pain
  • Antipyretic - fever reducer 
  • Anti-inflammatory (only seen after 3500mg aspirin per day, dangerous because it will lead to GI ulceration and bleeding)
  • Uricosuric - excretion of uric acid in urin (high doses >3g per day)
  • Uric acid retention in lower doses) 
  • Anti-platelet effect - (irreversible) inhibits COX which inhibits formation of thromboxane A2 - facilitates clotting

8

Why can aspirin be used to prevent strokes and heart attacks?

Aspirin inhibits COX which inhibits the formation of thromboxane A2 (normally causes vasoconstriction and platelet aggregation, facilitates clotting)

Low dose aspirin (81 mg) used to

9

What are some of the major adverse effects of aspirin?

  • Gastrointestinal irritant - bleeding, vomiting
  • Bleeding - irreversible effects on platelets - hypoprothrombinemia
  • Reye's Syndrome - contraindicated in kids with viral infections 
  • Salicylism - tinnitus, dizziness, nausea
  • Allergy to aspirin

10

What happens when a child is given aspirin when he or she has a viral infection?

  • Reye's Syndrome
    • They OD on aspirin because of loss of water with diarrhea and vomitus
    • Fluid in the brain (encephalitis) and hepatotoxicity = often fatal

Use acetaminaphen instead

11

What does it mean if you're allergic to aspirin, concerning other non-opioid anaglesics?

Cross-sensitivity to other NSAIDS

avoid aspirin and aspirin-like products and all NSAIDS

12

What consits of the aspirin hypersensitivity triad?

  • Aspirin hypersensitivity
  • Asthma
  • Nasal polyps

13

How do asthma and aspirin go together?

Asthma is a contraindication for aspirin use, allergic reactions look like asthma attacks - bronchial effects

And aspirin sensitivity develops over about 15 exposures

14

What are the contraindications for aspirin?

  • Allergy
  • Chronic gastritis
  • Gout
  • Anticoagulants (warfarin) - hemorrhage
  • Pregnancy 3rd trimester

15

What is the daily dose of aspirin for cardiovascular prevention?

81 mg

16

What is the full strength dose of aspirin, which is also administered during heart attacks to improve survival?

325 mg

17

What is the dosing for aspirin for analgesia and fever reduction?

  • Adults: 325-650 mg every 4-6 hours, up to 4 grams per day
  • Children: 10-15 mg/kg dose every 4-6 hours, up to 4 grams per day

18

Do you need to discontinue aspirin prior to dental treatment?

  • Low dose aspirin therapy - No
  • For highly invasive surgeries, must weigh risk to patient versus bleeding risks

19

What do you do if your patient comes in for treatment with cardiac stents and is on aspirin and antiplatelet drug (Plavix)?

Discontinue Plavis but not aspirin before surgery

20

Can you take patients off of aspirin therapy?

If patient is taking aspirin because of cardiac history, then consult the patient's physician before advising the patient to discontinue the drug = benefit must outweigh risks to the patient

Potential for stroke, MI if suddenly discontinue

21

What does it mean that aspirin effects are irreversible?

  • Blood platelet is anucleated - cannot form more cyclooxygenase
  • Aspirin effect lasts for life of platelet

22

What makes a person clot?

  • Fibrin
  • Endothelial cells continue to make thromboxane A2

23

What are some other salicylates that can be used topically?

  • Methyl salicylate - icy hot, ben gay
  • Trolamine salicylate - myoflex
  • Salicylic acid - compound V (warts)
  • Magnesium salicylate - Doan's pills (arthritis pain)