3 - Analgesics Flashcards
what is the classic mechanism by which all NSAIDs work?
act by inhibiting the synthesis of prostaglandins
what are the 3 NSAID drugs?
acetaminophen (tylenol - not an NSAID), ibuprofen (advil) and celecoxib (celebrex)
what are the indications for acetaminophen?
pain (mild) and fever
what is the pharmacology for acetaminophen?
analgesic and antipyretic
what is the mechanism of action for acetaminophen?
acts by inhibiting COX and enhancing 5-HT release
also acts centrally at hypothalamus - PG synthetase inhibition
in what ways is acetaminophen different from aspirin?
no inflammatory control, no platelet inhibition, central pain relief only, no GI effects and is SAFE in pregnancy
what are the common side effects of acetaminophen?
nausea, rash, headache
what are the hepatic side effects for acetaminophen?
acute hepatoxicity usually with high doses (>4000mg)
*drug of choice for suicide
what are the renal side effects for acetaminophen?
acute renal tubular necrosis and chronic analgesic nephropathy
what happens if you take acetaminophen with a combo acetaminophen/antihistamine drug?
there is an additive effect - hepatoxicity
what happens if you take acetaminophen with ASA?
there is an additive effect - nephrotoxicity
what happens if you take acetaminophen with topical lidocaine?
there is an additive effect - methemoglobinemia
what are the indications for ibuprofen?
mild to moderate pain, primary dysmenorrhea and fever
what is the mechanism for ibuprofen?
inhibits COX and reduces PG and TXA2 synthesis
what are the common side effects for ibuprofen?
headache, fluid retention, ecchymosis, and photosensitivity
what are the neuro side effects for ibuprofen?
tinnitus
what are the renal side effects for ibuprofen?
acute renal tubular necrosis and chronic analgesic nephropathy
what happens if you take ibuprofen with ASA or acetaminophen?
there is an additive effect - hemorrhagic risk
what happens if you take ibuprofen with acetaminophen or cyclosporine?
there is an additive effect - nephrotoxicity
what are the indications for celecoxib?
arthritis, ankylosing spondylitis, dysmenorrhea and acute pain
what is the mechanism of action for celecoxib?
selectively inhibits COX2 only and reduces PG synthesis
what are the common side effects for celecoxib?
headaches
what are the cardiovascular black box warnings for celecoxib?
stroke, CHF, MI
what are the GI black box warnings for celecoxib?
bleeding and ulceration/perforation = although these are minimal
what are the GI black box warnings for celecoxib?
bleeding and ulceration/perforation = these are minimal
what happens if you take celecoxib with NSAIDs (Ketorolac) or corticosteroids?
hemorrhage
what happens if you take celecoxib with azoles?
the metoblism of celecoxib is impaired
what is the contraindication/caution with celecoxib?
sulfonamide allergy
what type of pain do you use opioids for?
severe or chronic malignant or nonmalignant pain
what are the 4 types of opioids?
hydrocodone/acetaminophen (Vicodin), oxycodone (ocycontin), meperidine (demerol), fentanyl (duragesic)
what is the indication for hydrocodone/acetaminophen?
moderate - moderately severe pain
what is the pharmacology for hydrocodone?
FDA schedule II controlled narcotic analgesic and antitussive
what is the mechanism of action for hydrocodone?
acts through G-protein coupled Mu, Kappa, Delta opioid receptors
inhibits adenylyl cyclase activity and enhances K+ outflow = this hyperpolarizes nerves affecting neuronal excitability and muscle tone
also stimulates prolactin and growth hormone release
what are some common side effects for hydrocodone?
lightheadedness, dizziness, sedation, miosis (no tolerance), pruritus and flushing (histamine release - little tolerance)
miosis and itching
what are the CNS side effects for hydrocodone?
drowsiness, mood changes, elevated intracranial pressure - enhanced with head injury
what are the cardiovascular side effects for hydrocodone?
bradycardia/tachycardia and orthostatic hypotension
what are the respiratory side effects for hydrocodone?
dose-related respiratory depression at brain stem respiratory center (how you die from overdose)
what happens if you take hydrocodone/acetaminophen with anticholinergics?
additive effects is seen - constipation and paralytic ileus
what happens if you take hydrocodone/acetaminophen with sedating classic antihistaminics?
additive CNS depression
what happens if you take hydrocodone/acetaminophen with CAIs?
the acetaminophen impairs renal excretion of CAI - leading to CNS toxicity and metabolic acidosis
what is contraindicated/cautioned with hydrocodone/acetaminophen?
mydriatic procedures
what is the other analgesic (non NSAID or opioid)?
tramadol (ultram)
what is the indication for tramadol?
moderate - moderate severe pain
what is the pharmacology for tramadol?
central acting synthetic opioid analgesic
what is the mechanism of action for tramadol?
agonist at Mu receptors only and a weak inhibitor of NE/5-HT re-uptake
the mu agonist effect is greater with an active metabolite
what other drug class mechanism is similar to tramadol?
SNRIs = also inhibit NE and 5-HT re-uptake
what are the common side effects for tramadol?
headache, pruritus and flushing
what are the respiratory side effects for tramadol?
bronchospasm and respiratory depression
what are the CNS side effects for tramadol?
serotonin syndrome, seizures, and suicidal ideation
what are the cardiovascular side effects for tramadol?
orthostatic hypotension
what happens if you take tramadol with anticholinergics?
additive effect - constipation and paralytic ileus
what happens if you take tramadol with sedating classic antihistaminics?
additive effect - CNS depression
what happens if you take tramadol with azole antifungals?
the metabolism of tramadol is impaired
