Exam 3 - Analgesics and Antipyretics Flashcards
What are analgesics used for
Pain
Medication can act in the _____ and the ________
CNS
PNS
What are antipyretics used for
Fever
What does visceral mean?
Deep seated, organ related pain
What are prostaglandins
Hormone-like lipids
What effects do prostaglandins have
Bodily functions such as:
- inflammation
- pain
- uterine contraction
- “much more”
What is the natural role of prostaglandins
In defense and repair
Obtundation
Level of consciousness between alertness and coma just like “stupor” and lethargy
What are caplets
Tablets that are shaped like a capsule, that are smaller than a tablet, but have a smoother finish to allow for easy swallowing
Characteristics of obtundation
- reduced alertness
- slow response to stimuli
- less interested in environment
- tends to sleep more than normal (but w/ continued drowsiness between sleep)
Wong Baker pain assessment tool
Universal pain assessment tool
Tool intended to help patients care providers assess pain according to individual pt needs
0-10 scale for patient self assessment
FPS-R
Faces Pain Scale Revised (faces)
What can PCPs use if the pt is not able to communicate his/her pain intensity
Wong baker faces or behavioral observations
Iowa Pain Thermometer (IPT)
Looks like a thermometer (no pain to most intense pain imaginable)
PEG scale
- what # describes your pain in the last week 0-10
- what # best describes how, in the last week, pain has interfered w/ your enjoyment of life 0-10
- what # best describes how, during the last week, pain has interfered w/ your general activity 0-10
Psychometric testing of the defense and veterans pain rating scale (DVPRS) - 2016
4 supplemental questions measure how much pain interferes with:
- usual activity
- sleep
- mood
- stress
Non-pharmacological for pain
Relaxation therapies
Cognitive behavioral therapy
Physical modalities including:
- acupuncture
- chiropractic
- massage
- physical therapy
- osteopathic manipulation
Somatic pain
- superficial (on the skin or musculoskeletal system)
- easy to pinpoint location
- ACUTE MOST OF THE TIME
Visceral pain
- deep seated, organ related
- difficult to pinpoint
- CHRONIC MOST OF THE TIME
Examples of acute pain
Headache
Musculoskeletal pain
Dysmenorrhea
What is special about treatments for chronic pain
It requires prescription treatment and supervised medical care
Examples of chronic pain
Cancer
AIDS
Arthritis
Chronic back pain
Neuropathy
Why are toothaches no longer considered acute pain
Toothaches require referral
Can counsel on short term use until patient can see a dentist
Indication of acetaminophen
Fever and mild-moderate non-visceral pain
Acetaminophen absorption
Well absorbed from the GI tract
acetaminophen MOA
Thought to act centrally to inhibit prostaglandin synthesis as one pathway (but not well understood and complex)
Analgesic onset of acetaminophen
30 min
Analgesic duration of acetaminophen
4 hrs
Rectal admin of acetaminophen
Less bioavailable than the oral admin by 50-60%
Antipyretic onset of acetaminophen
30 min - 1 hour
When is max temperature reduction for using acetaminophen for fever
2 hours after taking
What is acetaminophen METABOLIZED by
Liver
What is acetaminophen EXCRETED by
Kidneys
What can happen if you exceed the max dose of 4 g of acetaminophen
Potentially hepatotoxicity, especially w/ chronic use
How much acetaminophen should someone take if they are at an increased risk for acetaminophen induced hepatotoxicity
Complete avoidance or conservative dosing of 2 g or less per day
Who is at increased risk for APAP induced hepatotoxicity
- liver disease
- concurrent use of other potentially hepatic drug
- poor nutritional intake
- consumption of 3+ alcoholic drinks per day
What is considered one alcoholic drink
12 oz beer
5 oz wine
1.5 oz of 80 proof liquor
Proof (alcohol)
The measure of alcohol content in a beverage
TWICE THE % ABV
Commercial formulation of acetaminophen
Rectal suppositories
Liquid
Liquid gels
Tablets
Powder packs that dissolve in liquid
Types of tablets in APAP
Caplets
Chewables
Dosing of IR APAP for adults
325 mg tabs
3250 mg per day OTC
Dosing of extra strength APAP for adults
500 mg
3000 mg per day OTC
APAP pediatric dosing
10-15 mg/kg/dose q4-6h PRN
Dosing of ER APAP for adults
650 mg
3900 mg per day OTC
Max adult APAP daily dose
4000 mg per day under HCP supervision
Max pediatric APAP dose
480 mg/dose, up to 5 doses
OR
75 mg/kg/day
How much APAP should you not exceed for pediatrics per day
2400 mg/day
FDA recommendations for APAP dosing
The lower max daily limits and that pediatric ORAL dosage forms be limited to a single strength (160 mg)
Stage 1 APAP toxicity
Nausea/vomiting
Drowsiness
Confusion
Abdominal pain
EARLY SIGNS AND SYMPTOMS MIGHT BE DELAYED
Stage 2 APAP toxicity
- first signs of hepatotoxicity
- begins 24-48 hrs after acute ingestions
- increased AST and ALT liver enzymes
- increased bilirubin w/ jaundice
- prolonged prothrombin time
- obtundation
Stage 3 APAP toxicity
- develops after 3-4 days and progresses to liver failure without treatment
- metabolic acidosis, encephalopathy, cerebral edema, renal failure
- may have continuous GI symptoms
Stage 4 APAP toxicity
- begins 4 days after ingestion
- can last weeks
- hepatic damage is reversible for the majority of cases
- some may need liver transplant
Antidote for APAP poisoning
N-acetylcysteine
What is the need for using N-acetylcysteine determined by
Rumack-Matthew nomogram
Warfarin-APAP interaction
- increased bleeding risk
- regular use of APAP while pt on warfarin should be discouraged
Clinically important APAP drug interactions
Alcohol
Warfarin
Severe liver damage may occur if…
An adult takes > 4 g of APAP in 24 hours
A child takes > 5 dosages in 24 hours (max daily amount)
The product is taken w/ other drugs that contain APAP
An adult has 3+ alcoholic drinks/day while using APAP
Limit of APAP in opioid rx combo products
325 mg/dosage unit
Analgesic of choice for warfarin patients
APAP
NSAIDs
Ibuprofen (motrin, advil)
Naproxen (aleve)
Acetylated salicylate NSAID
Aspirin
Non-acetylated salicylate NSAID
Magnesium salicylate
OTC naproxen strength
220 mg
OTC ibuprofen strength
200 mg tabs
MOA of NSAIDs (ibu + naproxen)
Central AND peripheral inhibition of COX, which then inhibits prostaglandins synthesis
Indication of NSAIDs
Fever
Mild-moderate non-visceral pain
NSAIDs metabolism/excretion
Metabolized by liver
Eliminated by kidneys
Onset of NSAID analgesic activity
30 min
Duration of analgesic activity for ibuprofen
6-8 hours
NSAIDs absorption
Well absorbed from the GI tract
Duration of analgesic activity for naproxen
12 hours