Pain Flashcards
Nociceptive vs. Neuropathic pain
Nociceptive: tissue damage stimulates sensory nerves releasing substances (ex. prostaglandins, substance P, and histmaine) which can result from injury to internal organs to skin, muscles, bones, joints, or ligaments
Neuropathic: damage or malfunction of nervous system (ex. fibromyalgia, diabetic neuropathy, chronic HAs, certain drug-induced toxicities - ex. vinca alkaloids)
Acute vs. chronic pain and General TX
Acute: begins suddenly, usually sharp and nociceptive in nature
Chronic: persistent pain for three or more months, can persist w/ visible injury (ex. crushed lumbar vertebrae) or w/o visible pain (ex. osteoarthritis, diabetic neuropathy)
-Subdivided into cancer pain or chronic non-cancer pain
General TX:
-Mild pain (1-3): non-opioid +/- adjuvant
-Mild/moderate pain (4-6): opioid for mild/moderate + non-opioid +/- adjuvant
-Severe (7-10): opioid for moderate/severe +/- non-opioid +/- adjuvant
**Non-opioids = APAP, NSAIDs
**Adjuvants = antidepressants, anticonvulsants, muscle relaxants
Acetaminophen:
-Brand
-MOA
-ROA
-Administration
-Dosing
Brand: Tylenol, FeverAll, Ofirmev
MOA: not well defined, but through to involve inhibition of prostaglandin (PG) synthesis in the central nervous system, resulting in reduced pain impulse generation
-Effects: pain and fever, but NOT anti-inflammatory
ROA: PO, rectal suppository (FeverAll), IV (Ofirmev)
Administration:
-Avoid using “APAP” abbreviation
-Injection: concentration of 10mg/mL in 100mL vials - caution w/ dosing (order as mg NOT mL and doses should be prepared in pharmacy
-Infant’s and children’s suspension: 160mg/5mL - use dosing syringe or dosing cup
Dosing:
-Pediatrics (<12 yo): 10-15mg/kg Q4-6H (max: 5 doses/day)
-Adults: maximum dose <4000mg/day from all sources
Acetaminophen:
-AVEs
-Warnings
-BBW
-DDIs
-Overdose
AVEs: generally well tolerated w/ PO administration
Warnings: severe skin rxns, renal imapirment
BBW: severe hepatotoxicity (can require transplant or result in death) w/ doses >4 grams/day or use multiple APAP-containing products)
-Risk of 10-fold dosing errors w/ injection
DDIs: avoid or limit alcohol (hepatoxocitiy), can be used w/ warfarin but if used chronically (>2 g/day) and can increase INR
Overdose: N-acetylcystiene (NAC, Acetadote): glutathione precursor administered IV or PO –> Rumack-Matthew nomogram uses the serum APAP level and time since ingestion to determine whether hepatotoxicity likely and the need for NAC
Acetaminophen Combination Brands:
1. With hydrocodone
- With oxycodone
- With codeine
- Norco, Vicodin
- Endocet, Percocet
- Tylenol #3 or #4
Acetaminophen Combination Brands:
1. With caffeine
- With aspirin + caffeine
- With caffeine + pyrilamine
- Excedrin Tension Headache
- Excedrin Extra Strength or Excedrin Migraine
- Midol Complete
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): MOA
-Non-selective NSAIDs
-Selective NSAIDs
-ASA
MOA: COX-1 and COX-2 enzymes catalyze conversion of arachidonic acid to prostaglandins and thromboxane A2 (TxA2)
-Non-selective NSAIDs: inhibit COX-1 and COX-2
-Selective NSAIDs: inhibit COX-2 only –> less GI AVEs since COX-1 protects grastric mucosa
-ASA: irreversible COX-1 and COX-2 inhibitor –> antiplatelet
NSAIDs: Class AVEs and recommendations
- Decreased renal clearance - caution or avoid in renal failure or additive nephrotoxic drugs
- Increased BP - caution in controlled HTN, avoid in uncontrolled HTN
- Nausea - especially with salicylates, can be minimized CF, switching to EC or buffered product, or changing to different NSAIDs
- Photosensitivity - avoid sun exposure, sunscreen, sun-protective clothing
- Premature closure of ductus arteriosus - avoid in 3rd trimester of pregnancy
NSAID Class BBWs and recommendations
- GI risk: increased risk of GI bleeds/ulcerations - greatest risk: hx of GI bleed or taking systemic steroids, SSRIs, SNRIs
- CV risk: increased risk of MI and stroke –> avoid use in CVD or risk factors
- Coronary artery bypass graft (CABG) surgery: CI after CABG –> antiplatelet (ASA) recommended after
NSAIDs: list drugs per their MOA and discuss the benfits/risks of each class
-Non-selective NSAIDs (inhibit COX-1 and COX-2)
-Selective NSAIDs (increased COX-2 inhibition)
-Salicylate NSAIDs (which ones are non-acetylated salicylates)?
Non-selective: have GI and CV risk and risk in post-operative CABG setting –> ibuprofen, indomethacin, naproxen, ketorolac, piroxicam, sulindac
-Others (less commonly used): meclofenamate, mefenamic acid, ketoprofen, fenoprofen, flurbiprofen, oxaprozin
Selective NSAIDs: lower GI risk, but increased MI/stroke risk (avoid in CV risk and avoid higher dose and longer duration in pts for risk of CV disease), same risk for renal complications –> celecoxib, diclofenac, meloxicam, etodolac, nabumetone
Salicyclate NSAIDs: aspirin/acetylsalicyclic acid
-Non-acetylated: salsalate, magnesium salicylate, choline magnesium trisalicylate, diflunisal, salicylate salts
NSAID Brand Names:
1. Ibuprofen
- Indomethacin
- Naproxen
- Advil, Motrin, NeoProfen (IV for closing the PDA)
- Indocin
- Aleve, Naprosyn
NSAID Brand Names:
1. Ketorolac
- Celecoxib
- Diclofenac patch
- Toradol
- Celebrex
- Flector
NSAID: Brand Names
1. Diclofenac Gel
- Meloxicam
- Aspirin
- Voltaren
- Mobic
- Ascriptin, Bufferin, Ecotrin, Bayer
NSAID Brand Names
1. Magnesium salicylate
- Naproxen + esomeprazole
- Naproxen + sumatriptan
- Doan’s Extra Strength
- Vimovo
- Treximet
Non-selective NSAIDs:
1. Ibuprofen dosing for adults and children. When using OTC, limit self-TX to under ___ days.
- _________ is high risk for CNS effects and should be avoided in psych conditions. It also has higher GI AVEs.
- Dosing for OTC naproxen. Why might prescribers choose naproxen?
- -Pediatrics: 5-10mg/kg/dose Q6-8H (max: 40mg/kg/day)
-Adults (OTC): 200-400mg Q4-6H (max: 1.2 grams/day) –> Rx max dose of 3.2 g/day
-Limit self TX to <10 days
- Indomethacin
- 220mg (200mg naproxen = 220mg naproxen sodium salt) Q8-12H –> prescribers may choose naproxen since the dosing can be BID
Non-selective NSAIDs:
1. __________ is sometimes used in those w/ reduced renal function and pts on lithium who require an NSAID.
- What are some risks associated w/ piroxicam?
- Sulindac
- High risk of GI toxicity and severe skin rxns –> used whn other NSAIDs have failed and may require PPI for GI protection
Ketorolac:
-Administration considerations
-AVEs
-Warnings
-BBWs
Administration:
-Nasal spray: one spray in each nostril for those <65 yo –> one spray in ONE nostril for those >/=65 yo
-Prime nasal spray five times before use –> no additional priming needed for additional doses, D/C 24 hours after opening
-Usually used after surgery, never before
AVEs: HA, injection site pain (often given IM)
Warnings: increased bleeding, acute renal failure, liver failure, anaphylactic shock
BBWs:
-Max combined duration IV/IM and PO/nasal is 5 days in adults
-PO ketorolac: for short-term moderate/severe pain ONLY as continuation of IV/IM ketorolac
-NOT for intrathecal or epidural use
-Avoid in advanced renal disease or at risk for renal impairment due to volume depletion, hypersensitivity rxns to ketolorac or other NSAIDs, labor and delivery, use w/ ASA or NSAIDs
-Dose adjustments needed in >/=65 yo or <50kg
Selective NSAIDs:
1. __________ has the highest COX-2 inhibition while the rest have some selectivity. Selective NSAIDs have lower risk for ______AVEs, same risk of _____AVEs, and increased risk of _______ AVEs.
2.__________ is CI in sulfonamide allergy.
- Celecoxib; GI; renal; CVD/MI/Stroke
- Celecoxib
Selective NSAIDs
1. Diclofenac is combined with _______ under the brand name _________ which has a BBW warning to avoid in females of childbearing potential unless capable of complying with effective contraceptive measures. What is the purpose of this combo?
- What is the maximum total dose for topical diclofenac? What is dosing for OTC?
- Misoprostol; Arthrotec –> used to replace gut-protective prostaglandins to decrease GI risk, but due to increased uterine contractions can terminate pregnancy and cause cramping/diarrhea
- 32 grams/day for total body
-OTC: 2 grams QID (max: 8mg/day) for hands, wrists, or elbows; 4 grams QID (max: 16mg/day) for feet, ankles, or knees
Salicylate NSAIDs:
-Drugs/Brands
-Dose of ASA (cardioprotective)
-Administration considerations
Drugs: aspirin (Ascriptin, Bufferin, Ecotrin, Bayer, Durlaza, Vazalore), salsalate, magnesium salicylate (Doan’s Extra Strength), choline mangensium trisaslicylate, diflunisal, salicylate salts
ASA dosing (cardioprotective): 81-162mg PO QD
Administration:
-To decrease nausea, use EC or buffered product or CF –> Ecotrin, Bufferin
-*PPIs may be used for GI protection w/ chronic use *
-Do NOT use Durlaza or Yosprala when immediate effect needed (ex. acute MI)
-Methyl salicylate popular OTC found in BenGay, IcyHot, Thera-Gesic, Salonpas
Salicylate NSAIDs:
-AVEs
-Warnings
AVEs: dyspepsia, heartburn, bleeding, nausea
-Toxicity can cause tinnitus
Warnings:
-Avoid w/ NSAID hypersensitivity (past rxn w/ trouble breathing), nasal polyps, asthma
-Avoid ASA in children and teenagers w/ any viral infection (Reye’s Syndrome: somnolence, N/V, lethargy, confusion)
-Severe skin rxns (rare)
-GI ulceration and bleeding
-Avoid in 3rd trimester of pregnancy due to fetal harm
NSAIDs: DDIs
- Additive bleed risk: steroids, SNRIs, SSRIs, antiplatelets, anticoagulants
- Caution using ASA w/ other ototoxic agents (ex. aminoglycosides, IV loop diuretics)
- Can increase levels of lithium and methotrexate
- Multiple NSAIDs should NOT be used together –> except in addition to low-dose ASA for cardioprotection (if using ASA and ibuprofen: take ASA one hour before or eight hours after ibuprofen)
