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
Warnings for NSAIDs
CHR may be exacerbated by NSAID use
Increased risk of renal toxicity in certain populations
Risk factors for renal toxicity in ibuprofen use
Advanced age
HTN
Diabetes mellitus
Using diuretics
Atherosclerotic CV disease
(Ass Holes Don’t Usually Ask)
Contraindications for NSAIDs
Contraindicated for perioperative pain after CABG surgery
Common adverse reactions w/ NSAIDs
Dyspepsia
Epigastric pain
Nausea
Anorexia
Dizziness
GI upset
Heartburn
Nervousness
Fatigue
(Don’t Eat Nsaids All Day, Gonna Have No Fun)
Uncommon adverse reactions w/ NSAIDs
Rash
Pruritis
Photosensitivity
Fluid retention/edema
Serious and rare adverse reactions w/ NSAIDs
GI ulceration
Perforation
Bleeding
Risk factors for serious adverse reactions w/ NSAIDs
- 60+
- Previous ulcer disease
- Concurrent use of anticoagulant (including aspirin)
- High doses
- Long treatment duration
- 3+ alcoholic drinks/day
What is a serious problem that NSAIDs can cause
Premature closing of ductus arteriosus, which may lead to heart failure in the infant
What do the adverse reactions of NSAIDs tell us
- use caution (or avoid) in renal failure
- can increase BP
- can cause nausea and upset stomach
- photosensitivity
- do not use in 3rd trimester of pregnancy (30+ weeks)
OTC commercial formulations of ibuprofen
Liquid
Tablet/caplet
Capsule
Liquid gels
OTC commercial formulations of naproxen
Capsules
Tablets/caplets
Gel caps
Liquid gels
AleveX
Available as topical lotions and sprays OTC
Does NOT contain naproxen
Motrin
Topical gel available
Does NOT contain ibuprofen
Adult ibuprofen dosing
200 - 400 mg q6-8h PRN
Daily max of ibuprofen OTC
1.2 g per day
Pediatric OTC ibuprofen dosing
5-10 mg/kg/dose q6-8h PRN
Pediatric OTC ibuprofen daily max
300 mg per dose, up to 4 doses
OR
40 mg/kg/day
Pediatric OTC ibuprofen dosing should not exceed
1200 mg/day
Naproxen OTC dosing
200 mg (220 mg naproxen sodium) q8-12h
Max OTC naproxen dosing
3 tablets in 24 hours
How much naproxen sodium is equal to regular 200 mg naproxen
220 mg naproxen sodium
How should you take ibuprofen liquid
Take with food or milk to help with stomach upset
How should you take ibuprofen tablets
Take with a full glass of water
What should happen w/ ibuprofen suspensions
Shake well
Why is naproxen sometimes preferred over ibuprofen
Naproxen has less frequent dosing (BID)
A good option for people struggling with adherence
Ibuprofen toxicity
- overdose rarely fatal
- minimal signs and symptoms of toxicity
GI manifestations of ibuprofen toxicity
Nausea
Vomiting
Diarrhea
Abdominal pain
Most serious effects of large naproxen overdose
Renal; failure
Neurological toxicity
Acid base changes
Drug interactions of ibuprofen
Alcohol (increased GI bleed risk)
Increased bleeding risk when taken w/ other agents that increase bleeding risk
Drug interactions of naproxen
Increased lithium and methotrexate levels when taken with NSAIDs
Multiple NSAIDs should not be used together
When can multiple NSAIDs be used together
NSAIDs used with low dose aspirin for cardio protection
Signs and symptoms of upper GI bleed
Hematemesis (vomiting bright red blood)
Coffee ground emesis
Melena (dark, tarry stool)
Signs and symptoms of lower GI bleed
Hematochezia (right red/fresh blood in feces)
Signs and symptoms of nonspecific GI bleed
Epigastric pain
Anemia
Syncope
Fatigue
Trade names for aspirin
Vazalore
St Joseph’s
Ecotrin
Bayer
Who is at increased risk for upper GI bleed
History of stomach bleed/ulcer
60+ years old
Concurrent use of NSAIDs, anticoagulants, and antiplatelet agents
Concurrent use of systemic corticosteroids
Infection w/ H pylori
Consumption of 3 or more alcoholic drinks per day
Use of aspirin/NSAID for longer than directed
Indication of salicylate NSAIDs (aspirin)
Analgesic
Antipyretic
MOA for aspirin
Inhibits COX-1 and COX-2, which inhibits prostaglandin synthesis
Primary peripheral action
Aspirin is hydrolyzed to _______
Salicylic acid
Absorption of aspirin
Well absorbed from GI tract
Rectal absorption of aspirin
Slow and unreliable
Onset of aspirin analgesic activity
30 min
What medications can be used in patients w/ an aspirin intolerance
APAP and methyl salicylate
Warnings for aspirin use
Avoid in children and teens due to Reye’s syndrome risk
In general, avoid other NSAIDs if patient has aspirin intolerance
Avoid in people w/ history of gout or hyperuricemia
Avoid use in patient w/ nasal polyps
Avoid use in patients with asthma
(for mnemonic: Nasal polyps, NSAIDs, Gout, Reye’s, Asthma)
(Never Never Give Real Aspirin)
Duration of aspirin analgesic activity
About 4-6 hours
What is the effect of patients with history of gout taking aspirin
Aspirin may cause reemergence of gout if used 2+ days
Asthma sensitivity and aspirin use
Not really allowed
10% of people with asthma have aspirin sensitivity
Two types of serious intolerance to aspirin
Cutaneous
Respiratory
Cutaneous intolerance to aspirin reactions
Edema
Angioedema
Respiratory intolerance to aspirin reactions
Bronchospasm
Laryngospasm
Rhinorrhea
Contraindications for aspirin
History of bleeding disorder (hemophilia)
Vitamin K deficiency
Hypoprothrombinemia
History of peptic ulcer disease
(For mnemonic: Hypoprothrombinemia, Bleeding, K, Peptic)
(Having Burger King Pizza)
Common adverse reactions to aspirin
Upset stomach (dyspepsia)
Heartburn
Bleeding
Nausea
Severe adverse reactions to aspirin
Stevens Johnson syndrome rash
Toxic epidermal necrolysis rash
GI ulceration and bleeding
When should pregnant people avoid using aspirin
Avoid in third trimester due to fetal harm
Commercial formulations of aspirin
Tablets (regular and chewable)
Liquid filled capsules (vazalore)
Which aspirin brand is formulated as liquid filled capsules
Vazalore
Commercial strengths of aspirin
81 mg
300 mg
325 mg
500 mg
Analgesic dosing for aspirin
325-650 mg q4-6h
Cardioprotective dosing for aspirin
81-162 mg once daily
Signs and symptoms of salicylism toxicity
Occasional diarrhea
Lassitude
Dizziness
Drowsiness
Hyperventilation
Confusion
Nausea and vomiting
Headache
Sweating and thirst
Tinnitus
(OLD Damn Hags Can Never Have Salicylism Toxicity)
Salicylism toxicity in aspirin use
Chronic toxic blood levels for at least 2 days
Salicylate intoxication due to aspirin
Higher blood levels than salicylism
Clinical manifestations depend on blood concentration
How is salicylate intoxication characterized
Mild
Moderate
Severe
Signs and symptoms of salicylate intoxication
Dehydration
Tachypnea
Acid base disturbances
Tinnitus
Pulmonary edema
Hemorrhage
Nausea and vomiting
Convulsion
Coma
Lethargy
(Don’t Take Aspirin To Prevent Hearing New Cat Calling Losers)
Important drug interactions in aspirin
Alcohol
Increased bleeding risk when taken w/ other agents that increase bleeding risk
Increased levels of lithium and methotrexate when taken w/ an NSAID
Multiple NSAIDs should not be used together
Salicylates are known to be
Ototoxic
Aspirin toxicity reactions in children
High fever
Serious hypoglycemia
Antidote for aspirin toxicity given in the ER setting
Gastric lavage or activated charcoal
What does taking an enteric coating with food produce
Longer absorption time due to prolonged gastric emptying time
When should you stop use of aspirin
3 days before a fecal testing
2-7 days before surgery
Do not use OTC aspirin for pain after tonsillectomy, dental extraction, or other surgical procedure
If the stomach acid is low (due to acid-suppressing meds like a PPI), what might happen to a product with an enteric coating
Product may dissolve in the stomach, which can cause stomach irritation
What can the use of aspirin produce
Positive result on fecal occult blood testing
Does enteric coating decrease the risk of GI bleed
NO
It is advertised as safer, but isn’t actually
When should you NOT use an enteric coated product
If you are in need of rapid pain relief
Buffered dosage forms
Tablet and effervescent forms
What is the point of a buffered dosage form
Combines an antacid w/ aspirin to absorb more rapidly
Common buffer dosage forms
Calcium carbonate
Aluminum hydroxide
Magnesium hydroxide
Sodium bicarbonate
(CAMS)
Effervescent tablets
Use the sodium bicarb and may contain large amounts of sodium
Watch for patients on sodium reduced diets
*What should you be aware of before recommending effervescent tablets to a patient
Make sure they are not on a sodium reduced diet because they often have a very high sodium content
Do buffered dosage forms decrease the risk of GI bleed
NO
Marketed as safer but isn’t actually
What does the progressive neurologic damage in Reye’s syndrome START with? What does it progress to?
Starts w/ lethargy
Progresses to:
- delirium
- confusion
- seizures
What is Reye’s syndrome
- progressive neurologic damage
- fatty liver encephalopathy
- hypoglycemia
- mortality rate around 50%
Reye’s syndrome happens in what patient population
Almost exclusively in children and teenagers
Cause of Reye’s syndrome
Cause is technically unknown
Using salicylate to treat a viral illness such as flu and chicken pox is associated w/ it
What does aspirin do to platelet function
Irreversibly inhibits platelet function
Meaning the inhibition continues for the duration of the platelet’s life
Salicylate NSAID legal requirements
GI risks
Cardiovascular risks
Contraindicated w/ CABG
Alcohol
Reye’s syndrome
Motrin dual action combination products
Acetaminophen and ibuprofen
Advil dual action combination products
Acetaminophen and ibuprofen
Bayer back and body combination products
Aspirin and caffeine
Excedrin combination products
Acetaminophen
Aspirin
Caffeine
BC combination products
Aspirin and caffeine
Max strength BC combination products
Acetaminophen
Aspirin
Caffeine
OTC analgesic use in the elderly population
Acetaminophen may be the safest
Increased risk of NSAID adverse reactions
More likely to have renal issues
More vulnerable to GI toxicity and HTN/renal impacts
Aspirin use in pregnancy
No aspirin in pregnancy, ESPECIALLY in the 3rd trimester
Which OTC analgesics can be used in children 2+
Acetaminophen
Ibuprofen
Which analgesics can be used in children 12+
Acetaminophen
Ibuprofen
Naproxen
NSAID use in pregnancy
NSAIDs are not shown to be teratogenic
Contraindicated in 3rd trimester
Acetaminophen use in pregnancy
Crosses the placenta but is considered safe for pregnancy
Which analgesic is preferred in breastfeeding patients
Ibuprofen
It is considered the safest because of the very low concentration in breastmilk and lack of ill effect in infants
Acetaminophen use in infants
Crosses into breastmilk at a low ration
**may cause rash in infants that subsides after discontinuation
Naproxen use in breastfeeding
DO NOT USE
Aspirin use in breastfeeding
DO NOT USE
Renal impairment
Caution w/ salicylates and other NSAIDs
Ask renal doctor to recommend
Hepatic impairment
Caution to be used w/ acetaminophen
Prolonged use/high doses must be avoided
Aspirin allergy
15% tartrazine cross reactivity
This is because tartrazine is a yellow dye #5
If a person is allergic to aspirin, what is their cross reactivity with APAP, ibuprofen, and naproxen
7% cross reactivity w/ APAP
98% cross reactivity w/ ibuprofen
100% cross reactivity w/ naproxen
Dosing preference
- BID dosing w/ naproxen
- ER APAP dosed q8h