Non-Opioid Lecture Part 3 (NSAIDS) Flashcards
Mechanism of action of NSAIDS
Inhibit cyclooxygenase - reduces formation of prostaglandin precursors and thromboxane from arachidonic acid
- Non-selective = inhibits both COX-1 & COX-2
- Selective = inhibits COX-2
NSAIDS peak after how long?
What are they metabolized by?
Excreted by what organ?
Half-life?
- Peak in 1 to 2 hours
- Metabolized by liver
- Excreted by kidney
- Half-life varies by product
3 actions or effects of NSAIDS
- Analgesic
- Antipyretic
- Anti-inflammatory
Difference between NSAIDs and Aspirin on how they affect the blood platelets
NSAIDS have a reversible effect on blood platelets
- Effect lasts only as long as the drug is in the bloodstream
Aspirin have an irreversible effect on blood platelets
If a patient is taking low-dose aspirin (81 mg) to prevent stroke and have cardioprotection, how would you prescribe them to take ibuprofen?
Dose the ibuprofen at least 30 minutes or longer after aspirin ingestion or more than 8 hours before aspirin ingestion to avoid attenuation of aspirin’s effect
Occasional use of ibuprofen or other NSAIDS pose little risk for attenuation of anti-platelet effects of low-dose aspirin why?
This is because the effects of aspirin on platelets are permanent (last for the life of the platelet)
Indications for NSAIDS
Dental: pain, fever, inflammation
Medical: osteoarthritis, rheumatoid arthritis, gouty arthritis, fever, dysmenorrhea and pain
Name two examples of NSAIDS that are NONSELECTIVE
- ibuprofen (advil, midol, motrin, ultrprin = OTC; motrin = prescription brand name)
- naproxen (aleve = OTC; Anaprox, Naprosyn = prescription brand names)
Adverse events with NSAIDS?
- Increased risk of MI, stroke
- New onset or worsening of hypertension
- Compromised renal function
- contraindicated in patients with advanced renal disease
- excessive or chronic use = nephrotoxicity
- Gastrointestinal ulceration, irritation, bleeding and perforation
- CNS effects
- Adverse skin reactions
- Avoid in patients with aspirin allergy
- Use with caution if decreased hepatic function
Target organ for NSAIDS
Kidney (not liver)
Inhibiting prostaglandins shuts down what?
Renal blood flow
What is the OTC dose for ibuprofen?
200 mg tablets
What is the prescription dose for ibuprofen?
400-800 mg
Describe the half life of ibuprofen
2-4 hours, short half-life = must take frequently
How rapid is the onset of analgesia and duration of action?
- Rapid onset of analgesia (30-60 minutes)
2. Short duration of action (4-6 hours)
Dental dosing of ibuprofen (Motrin)
Children: 4-10 mg/kg/dose every 6-8 hours
Adults: 200-400 mg/dose every 4-6 hours for a maximum daily dose of 1200 mg.
Preoperative use of ibuprofen
a dose of 400-600 mg every 6 hours for 24 hours before the appointment decreases postoperative edema and hastens healing time.
Very good thing and can reduce opioid use after operation
“Ceiling effect” for dental pain
optimal analgesia occurs at 400 mg dose.
If you prescribe more, you get the anti-inflammatory effect. (this is used for examples like arthritis) 400-800 mg 4 times daily with a maximum dose not to exceed 3200 mg. This is for patients with chronic inflammatory pain
Give the example of writing a prescription for ibuprofen
Rx: ibuprofen 400 mg tablets
Disp: 16 tablets
Take 1-2 tablets by mouth 3-4 times per day as needed for pain. Do not exceed 8 tablets within 24 hours
What is the OTC brand name for naproxen? What about the 2 prescription names/
OTC = Aleve Presc. = Anaprox, Naprosyn
Describe the onset of analgesia, duration of action and half life for naproxen
onset of analgesia: 1 hour
Half-life: 12-17 hours
Duration of action: analgesia < 7 hours; anti-inflammatory <12 hours; peaks after 2 weeks
Very long half life
Dental dosing of naproxen?
adults: 500 mg initially, then 250 mg every 6-8 hours
What is the maximum dosage of naproxen per day?
1250 mg/ day
What NSAID has the longest half-life in dentistry?
piroxicam (Feldene) = longest acting of all NSAIDS
half-life of 45-50 hours
10 mg 2 times per day
Name 4 other important NSAIDS in dentistry
- piroxicam (Feldene)
- flurbiprofen (ANSAID)
- ketorolac (Toradol)
- diflunisal (Dolobid)
Which of the NSAIDS is taken primarily by injection?
ketorolac (Toradol)
- Severe acute pain requiring analgesia at opioid level
Which of the NSAIDS is considered a “super aspirin”? Does this NSAID have a better efficacy than aspirin? Why would it have an advantage?
diflunisal (Dolobid)
- No greater efficacy than aspirin
- KNOW THIS** Advantage = longer half-life; only have to take 8-12 hours versus 4-6 hours with aspirin. This improves compliance
When writing a prescription for pain, what are the 2 ways to do it?
- as needed for pain = “prn”
- Every 6 hours
- This is done so that the blood level never falls below the therapeutic blood level
Name 3 psychological considerations when prescribing
- A prescription drug gives more relief to a patient than an OTC drug = psychological
- More relief with expensive drug vs cheap drug
- More relief from colored pills vs. white pills
What is the only selective NSAID?
celecoxib (Celebrex) –> only one available
- COX 2 inhibitor
- obtained original approval for arthritis pain
T or F, COX-2 inhibitors have better adverse events profile than non-selective
True
What are some benefits of anti-inflammatory effect of COX-2 inhibitor
- Celebrex has been shown to reduce risk for adenocarcinoma of the colon
- Improvements in lung cancer, and possibly oral cancer
- Celebrex shown to delay onset and degree of severity of Alzheimers disease
Dosing for celecoxib (Celebrex)
Initial 400 mg dose, followed by an additional 200 mg dose if needed on day 1. Then, maintenance dose: 200 mg twice daily as needed
- Used for acute dental pain
What does Celebrex contain that some might be allergic
Sulfa atom
COX-2 inhibitor is contraindicated in what 2 scenarios
- Aspirin/NSAID allergic patients
2. Patients with history of gastritis/gastric ulcer/GI bleeding
If a patient is on Methotrexate, what drug for pain relief would you give?
Tylenol (acetaminophen), ibuprofen/aspirin inhibits the breakdown of methotrexate, causing toxicity
Is it ok for patients on Lithium to take NSAIDS? Why?
No, NSAIDS block excretion of lithium, resulting in toxicity
Is it ok to take multiple NSAIDS together?
taking multiple together can give an additive toxic effect
What is the adverse effect of taking alcohol with NSAIDS?
increases the risk for GI bleeding associated with aspirin and NSAIDS
Aspirin and NSAIDS may decrease the effectiveness of what medications?
Many common antihypertensive medications
Acetaminophen nickname?
APAP (N-Acetyl-P-Aminophenol)
T or F, acetaminophen acts centrally and acts more upon peripheral COX than CNS COX
False, It does act centrally but acts more on CNS COX rather than peripheral COX
acetaminophen is metabolized by what organ?
acetaminophen is excreted by what organ?
Half life of acetaminophen
Peak plasma level occurs when?
Metabolized by liver
Excreted by kidneys
Half-life: 1 to 4 hours
Peak plasma level occurs in 1 to 3 hours
T or F, acetaminophen metabolite is hepatotoxic but not nephrotoxic
False, both hepatotoxic and nephrotoxic
Actions of acetaminophen
- Analgesic
2. Antipyretic
Maximum dose of acetaminophen
4000 mg (4 grams per day)
T or F, acetaminophen and aspirin are equally efficacious (reduces same degree of pain) and equally potent (same dose in milligrams needed for effect)
True
How is acetaminophen less useful clinically?
It is not an anti-inflammatory
Dental dosing for acetaminophen
Children: 10-15 mg/kg/dose every 4-6 hours as needed
- do not exceed 5 doses (2.6 grams) in 24 hours
Adults: 325-650 mg every 4-6 hours or 1000 mg 3-4 times per day. Do not exceed 4000 mg per day.
**Do not exceed 2 grams per day in patients who regularly consume alcohol
Avoid using acetaminophen in what patients?
- Liver disease/dysfunction
- Alcohol
- **In patients on warfarin (Coumadin)
Why is acetaminophen contraindicated with warfarin (Coumadin)?
It causes enhanced anticoagulation
- Increased bleeding risk
