Pain Flashcards
Define nociceptive pain.
Pain that occurs when sensory nerves (nociceptors) identify tissue damage.
Pain that does not result in tissue injury or damage but from damage or malfunction of the nervous system is commonly referred to as?
neuropathic pain
Examples of Neuropathic pain
Fibromyalgia
Diabetic neuropathy
What analgesic regimen is indicated for mild pain (1-3)?
Non-opioid +/- adjuvant
What analgesic regimen is indicated for moderate pain (4-6)?
Opioid for mild-moderate pain +/- Non-opioid +/- adjuvant
What analgesic regimen is indication for severe pain (7-10)?
Opioid for moderate-severe pain +/- Non-opioid +/- adjuvant
Acetaminophen -
Brand/Drug Class/MOA/MDD/Dosing <12 yoa/Boxed Warning
Brand: Tylenol
Drug Class: antipyretic
MOA: inhibit prostaglandin synthesis
MDD: < 4g/day
Dosing in pediatrics: 10-15 mg/kg Q4-6H using 160mg/5mL
Boxed Warning: hepatotoxicity if > 4g/day
Antidote for acetaminophen overdosage
N-acetylcysteine (NAC)
based on serum level and time since ingestion
NSAIDs MOA
1) Non-selective NSAIDs blocks both COX enzymes
2) COX-2 selective NSAIDs blocks COX-2 only - decreasing GI risk (b/c COX-1 protects the gastric mucosa)
3) Aspirin is an irreversible COX-1 and 2 inhibitor and is an effective antiplatelet - cardioprotection
NSAID use is contraindicated after what type of surgery?
Coronary Artery Bypass Graft (CABG) but only aspirin is recommended due to the antiplatelet effects
Side effects of all NSAIDs
Increase BP (avoid in uncontrolled HTN) Photosensitivity Premature closure of the ductus arteriosus (if used in 3rd trimester) Nausea/dyspepsia (take with food) Abdominal pain ~ likely due to GI bleed
What NSAIDs can be used within 14 days after birth to close a patent ductus arteriosus (PDA)?
IV indomethacin or ibuprofen
in most cases the PDA closes on its own
What is ductus arteriosus (DA)?
It’s a duct that connects the pulmonary artery to the aorta, allowing oxygenated blood to flow to the baby, bypassing the immature lungs.
Ibuprofen dosing in adults & pediatrics
Adults: MDD 3.2g/day
Pediatrics: 5-10 mg/kg Q6-8H
How often is Naproxen dosed?
BID
Which NSAIDs increase COX-2 selectivity and have a lower risk for GI complications but still have a high risk for MI/stroke, as well as the same risk for renal complications?
Generic/Brand
celecoxib (Celebrex)
diclofenac (Voltaren)
meloxicam (Mobic)
nabumetone
etodolac
What drug is used to replace the gut-protective prostaglandins to decrease GI risk?
Misoprostol
Also used to increase uterine contractions (terminate pregnancy) and causes cramping and diarrhea
Which NSAID has the highest COX-2 selectivity and should be avoided if patient has a sulfa allergy?
celecoxib (Celebrex)
Name the salicylate NSAID and what’s the dosing?
Aspirin (Acetylsalicylic acid)
Cardioprotection dosing: 81-162 mg/day
**Avoid in children & teenagers due to Reye’s Syndrome (sx: somnolence, N/V, lethargy, & confusion)
Yosprala contains what agents?
Omeprazole + Aspirin
*PPIs used to protect the gut with chronic NSAID use**
Counseling point if patient is taking both aspirin and ibuprofen
If aspirin is used for cardioprotection and ibuprofen for pain, take aspirin 1 hour before or 8 hours after ibuprofen.
Concurrent use of NSAIDs with Lithium and MTX can do what to which levels?
NSAIDs can increase the levels of Lithium & MTX
Name a non-salicylate drug.
magnesium salicylate (Doan’s Extra Strength)
Name the topical products that contains methyl salicylate.
Bengay, IcyHot, & Salonpas
When a higher opioid dose is needed to produce the same level of analgesia, this is due to what?
Tolerance
When physical withdrawal symptoms occur when an opioid is stopped or a dose is missed, this is called?
Dependence
Sharp spikes of severe pain that occur despite the use of an ER opioid such as transmucosal immediate-release fentanyl (TIRF) drugs, is called?
Breakthrough pain and only indicated for cancer patients
MOA of opioid analgesics
mu receptors agonists that produce pain relief but can also cause euphoria and respiratory depression
What scheduled classes are the different formulations of codeine?
C-II: codeine tablet
C-III: tablet/capsule combination products (ex: Tylenol #2/3/4)
C-IV: oral solution combination products (Cheratussin AC)
Boxed warnings of opioids & Side effect
Respiratory depression & death
Avoid use in ultra-rapid metabolizers of codeine due to a CYP450 2D6 polymorphism
SE: constipation
What is the brand name of fentanyl oral transmucosal lozenge on a stick “lollipop?”
Actiq
fentanyl dosing
1 patch Q72H
When can a patient start fentanyl patches?
A patient who has been using equivalent to morphine 60 mg/day or more for at least 7 days can be converted to fentanyl patches.
Duragesic patches can be covered ONLY with what 2 permitted adhesive film dressings?
Bioclusive or Tegaderm
What is the dose acetaminophen in hydrocodone IR?
325 mg APAP
Dilaudid
Generic/Dosing
Generic: hydromorphone
PO: 2-4 mg Q4-6H PRN
IV: 0.2-1 mg Q2-3H PRN
- *potent, start low and titrate due to high risk of overdose
- *med error w/ high potency, use in opioid-tolerant patients only
What opioid agent (brand/generic) is a major CYP3A4 substrate that has a life-threatening boxed warning for QT prolongation and can decrease testosterone and contribute to sexual dysfunction?
methadone (Dolophine)
Which opioid is no longer recommended as an analgesic due to its short duration and its serotonergic effects?
(generic/brand)
meperidine (Demerol)
What are morphine brand names & side effect.
ER: MS Contin, Kadian
Injection: Duramorph, Infumorph
SE: Pruritus (diphenhydramine can be given to block histamine-induced pruritus)
Which opioids are CYP3A4 substrates?
Fentanyl
Hydrocodone ER
Oxycodone
Methadone
Which oxycodone brand is taken on an empty stomach?
Opana
Brand names of oxycodone formulations
IR: Roxicodone
CR: OxyContin
+ acetaminophen: Endocet or Percocet
Opioid Drug Interactions
Avoid concurrent use with BZDs & Etoh
Do not use in patients with COPD or sleep apnea (increase risk of hypoxemia)
Avoid use with CYP3A4 inhibitors
Opioid Dosing Conversion
**round down to reduce risk of overdose
Morphine - 10mg (IV/IM) - 30 mg (PO)
Hydromorphone - 1.5 mg (IV/IM) - 7.5 mg (PO)
Oxycodone - 20 mg (PO)
Opioid allergy
Common drugs in the same chemical class that cross-react with each other have “cod,” “morph,” or “norph” in the name.
CODeine hydroCODone oxyCODone MORPHine hydroMORPHone oxyMORPHone bupreNORPHine
What drug is first-line for opioid-induced constipation?
Stimulant laxatives, including senna with or without a stool softener.
bisacodyl tablet - prophylaxis
suppository - treatment
If patients failed therapy with stimulant laxatives +/- stool softeners. What is an alternative treatment?
Peripherally-acting mu-opioid receptor antagonists “PAMORAs”
- methylnaltrexone (Relistor)
- naloxegol (Movantik)
Chloride channel activators - lubiprostone (Amitiza)
Name the centrally-acting analgesics
tramadol (Ultram) - C IV
- do not use w/ concurrent MAOIs or within 14 days
tapentadol (Nucynta) - C II
- increase risk of seizures
Opioid-induced respiratory depression (OIRD) risks
Hx of previous overdose
Substance abuse
Using large doses (> 50 morphine mg equivalent dose)
Using with BZDs, gabapentin or pregabalin
Comorbid illness, like respiratory & psychiatric disease
Opioid Abuse Agents
buprenorphine is a partial mu-agonist (agonist at low doses & antagonists at higher doses).
naloxone is an opioid antagonist; it replaces the opioid on the mu receptor.
- given alone (nasal or injection) is used for OD
buprenorphine/naloxone combination is used as alternatives to methadone.
- buprenorphine suppresses withdrawal symptoms - naloxone helps prevents misuse
Opioid overdose management
- s/sx of OD: extreme sleepiness, shallow breathing, blue/purple fingers/lips, pinpoint pupils, slow
HR/BP - Give naloxone & call 911.
- opioids last longer than naloxone so multiple doses may be needed, CPR may be needed
Naloxone is available in 3 options (what are they?)
- Evzio (auto-injector): easy to administer with visual and voice instructions, each auto-injector = 1 dose (no longer available but available up to expiration date)
- Narcan (nasal spray): onset of action is slower than injection, a single-use nasal spray is 4 mg administered in 1 nostril, repeat PRN
- Naloxone (injection): multiple size vial, separate syringe will be needed, may need to repeat doses Q2-3 minutes until medical emergency arrives.
To prescribe for opioid dependence: prescribers need what?
Drug Addiction Treatment Act (DATA 2000) waiver; the DEA will issue a unique identification number to the prescriber “starts with an X”
An injectable adjuvant can be added to opioids in intrathecal (epidural) pain infusion pumps for patients with cancer pain. What drug is used?
Clonidine
Which drug was approved for osteoarthritic knee pain and is administered by injection into the knee joint (intra-articular) to provide 12 weeks of pain relief without opioids?
triamcinolone acetonide ER (Zilretta)
What scheduled class is gabapentin?
C VI
What scheduled class is pregabalin?
C IV
What scheduled class is carisoprodol? Brand?
C IV
Soma
Generic & Side effect of Zanaflex
tizanidine
SE: hypotension & xerostomia
Generic & Side effect of Lioresal
baclofen
SE: all muscle relaxants: sedation, dizziness, confusion, asthenia (muscle weakness)
What topical adjuvant is dosed TID-QID?
capsaicin
Dosing of Lidoderm? and counseling?
Dosing: Apply to painful area 1-3 patches/day and worn up to 12 hours/day.
can be cut | no more than 3 patches at one time
Diclofenac gel dosing
Dose for hands, wrists or elbows: 2 g QID (MDD 8 g/d)
Dose for feet, ankles, or knees: 4 g QID (MDD 16 g/d)
**do not wash or bathe treated areas for at least 1 hour after application*
