P5 PHARMACOLOGY Flashcards
Pharmacology of osteoarthritis
examples of topical NSAIDs
methyl saIicyIate cream
DiethyIamine saIicyIate (LIoyd’s cream)
DicIofenac cream
Topical capsaicin
Examples of intra-articular glucocorticoid injections
TriamcinoIone acetonide
MethyIprednisoIone acetate
Maximum dose of paracetamol
4 gm/day
OD of paracetamol can cause
acute liver failure
MOAs of oral NSAIDs
- non selective COX-1 & COX2 inhibitors
- selective COX2 inhibitors
common example of opioid analgesic
tramadol
oral NSAIDs should be co-prescribed with
PPIs / H2 receptor inhibitor
reactive intermediate in paracetamol metabolism that in OD can lead to liver failure
NAPQI=N-acetyIe-para-benzoquinone imine
LEVELS of arachidonic acid & peroxidase in broken cells
both high
LEVELS of arachidonic acid & peroxidase in normal intact cells
both low
Intermediate in acetaminophen metabolism that crosses BBB
p-aminophenol
Mechanism in which AM404 activates CB1 receptors
by inhibition of anandamide re-uptake
CB1 & TRPV1 are involved in transmission and modulation of
pain
PH levels in inflammation
high Ph
strongly recommended intervention for knee & hip osteoarthritis
intra-articular glucocorticoid injection
indications for IAGC use
- Severely inflamed large monoarthritis
- unresponsive to NSAIDs
- intolerance to NSAIDs
Glucocorticoids Preparations
1- non-ester preparations
2- ester preparations
enzyme that is needed to hydrolase ester preparations
Cellular esterases
Examples of steroid injections
- methylprednisolone acetate
- dexamethasone acetate
-dexamethasone sodium
adverse effects of IACG
Infection
capsular calcification
tendon rupture
cutaneous atrophy
post injection flare
Osteonecrosis
Absolute contraindication for corticosteroid injections
- local / intra-articular sepsis
- bacteremia
- intra-articular fracture
- joint instability
factors affecting systemic absorption of anaesthetic
- dosage
- vasodilating properties
- presence of vasoconstrictor agent
- nature of administration site
- drug-tissue binding
Vasoconstrictor agents
adrenaIine
NoradrenaIine
FeIypressin
vasodilating agents that has the highest vasodilating properties
bupivacaine
etidocaine
advantages of vasoconstrictor agents while administrating anaesthesia
- Prolong & increase the depth of anaesthesia
- reduce or Limit the systematic toxicity
-render the area of injection Iess hemorrhagic
Mechanism in which vasoconstrictors reduce the systemic toxicity
by delaying its absorption into generaI circulation
order of loss of sensation in anaesthesia
pain
Temperature
touch
Pressure
order of nerve block
-SmaII myeIinated fibers
-SmaII unmyeIinated fibers
Large myeIinated fibers
Large unmyeIinated fibers
biotransformation of amino esters is done by
plasma pseudocholinesterase
amino esters Systemic Toxicity
is more likely to occur in
Individuals with genetically determined pseudochoIinesterase deficiency
amino esters hypersensitivity reactions are more likely due to formation of
PABA = para-aminobenzoic acid
biotransformation of amino amides is done by
Iiver (Cytochrome P 450)
amino amides Systemic Toxicity
is more likely to occur in
individuaIs with hepatic diseases, reduction in hepatic bIood fIow (due to heart faiIure, β-bIockers), hepatic enzyme inhibitors
