Week 6: Anti-Inflammatories Flashcards
Prototype Drugs for the Anti Inflammatory Category
- aspirin (Aspirin)
2. acetaminophen(Tylenol)
3. indomethacin (Indocin)
4. ibuprofen (Motrin, Advil, etc.)
5. celecoxib (Celebrex)
6. ketorolac (Toradol)
7. etanercept (Enbrel)
8. hydroxychloroquine (Plaquenil)
9. azathioprine (Imuran)
10. allopurinol (Zyloprim)
11. colchicine (Colcrys)
Prostaglandins
Modulate important components of inflammation: Body Temp increases, Pain Increases, Platelet Aggregation Increases
They are converted from arachidonic acid by cyclooxygenase (COX) enzyme
Chronic Inflammation = ???
More prone to blood clotting
COX 1
The first kind of COX enzyme that converts arachidonic acid to prostaglandins
HAS PROTECTIVE EFFECTS
Found in all tissues
Decreases stomach acid and increases gastric mucus = protects the stomach
Increases platelet aggregation = may prevent bleeding
COX 2
Second kind of COX
A major mediator of bad effects - we want to stop this one
Found mainly in INJURED tissues
increases inflammation
increases pain
causes fever
NSAIDS
Non steroidal anti inflammatory
many NSAIDS inhibit prostaglandin synthesis and many do so by targeting both COX 1 and 2
How do NSAIDS cause many adverse effects we see?
it blocks COX 1 (the protective effects/good stuff)
Salicylates
Class of anti inflammatories - active form
is so irritating it can only be used externally - so it includes Acetylsalicylic acid (Aspirin, ASA)
Prototype drugs for Salicylates
Aspirin (Metabolizes into the active metabolite of salicylic acid)
Aspirin is a ___ drug
ancient
Aspirin is used for what effects
Analgesic
Antipyretic
Anti Inflammatory
Anti Platelet
What is unique about aspirin
IRREVERSIBLY INHIBITS COX - good blocking COX 2 but blocks COX 1 which is also bad
What is important to know about clotting after taking aspirin
As long as ASA is still lingering it will effect COX thus impacting the life of the platelet as well
Every platelet of any age is effected by ASA, so once a platelet is effected it cannot clot well for the rest of its lifespan
Side effects from ASA are mostly due to what
inhibition of COX 1 enzyme
Since salicylic acids can only be sued externally what reason are they commonly used for
acne products
Actions of Aspirin
- Analgesia
- Antipyretic
- Anti Inflammatory
- Gastrointestinal
- Anticoagulation
What is the analgesia action of aspirin
- Effects PERIPHERAL more, not central, by preventing sensitization of pain receptors by inhibiting prostaglandin synthesis !!! - This is the main way ASA works, periphery
- Works somewhat centrally on the hypothalamus by modifying pain perception, but the action here is little and also the antipyretic effect takes place here
What is the antipyretic action of Aspirin
believed to act directly on heat regulating center in the hypothalamus
decreases fever but not below the set point
What is the anti inflammatory action of aspiring
inhibits prostaglandin synthesis (by irreversibly impacting Platelets and COX 1 and 2)
What is the GI action of aspirin
local irritation and also stimulation of the vomiting center in brain - since it blocks COX 1 it increases stomach acid and it will cause less mucus so there is a greater irritation risk
Also* if a stomach ulcer occurs you will bleed more from the anticoagulant effect and the acid will irritate flesh
What is the Anticoagulation effect of Aspirin
IRREVERSIBLY inhibits platelet aggregation, weakly inhibits prothrombin synthesis, and prolongs bleeding time
MORE LIKELY TO BLEED
Uses for Aspirin
- Effective in pain from inflammation (due to prostaglandin increases), BUT NOT sharp pain due to sensory nerve stimulation
- Anti pyretic effects - peripheral and central inhibition of prostaglandin (pyretic) activity
- Anti inflammatory - inhibits prostaglandin activity
- Anti platelet - antithrombotic effect by inhibiting thromboxane A2, a prostaglandin that induces platelet aggregation
What is the main reason we use ASA nowadays
Its Anti Platelet Effect
It blocks Thromboxane A2 which is a prostaglandin that induces platelet aggregation!
People are less likely to develop blood clots - daily ASA to prevent clots that cause MI/DVT - inhibits TXA-2 to stop platelets
It is important to know what about the excretion of ASA
IT IS EFFECTED BY URINE PH - if someone overdosed on it we could modify their urine pH to increase secretion
What are the ADRs of ASA like
widespread- many different effects - most are GI
What are the various ADRs of Aspirin
- Most are GI* - NOT an allergy but could be a SE - epigastric distress, NV, ulceration
- Respiratory - respiratory stimulation, due to increased O2 consumption - resp stimulation NOT usually a problem only seen taking too much
- CV - large doses cause peripheral vasodilation - NOT common due to low doses
- Allergic - low, but can cause asthma, angioedema, and urticaria
- Blood - Anemia, Thrombocytopenia, Coagulation Effects - iron deficiency with bleeding, low platelets and bone marrow depression (effects platelet fxn more than numbers), increases cap. permeability and increases bleeding time
- CNS - tremors, HA, vertigo, tinnitus, diplopia, agitation, can be ototoxic
- Metabolism effects
What is rare but can occur with too much aspiring
hepatic and renal toxicity
Why do we never give children with flu like illnesses aspirin?
Risk for Reyes Syndrome - potentially fatal swelling in brain and liver along with hypoglycemia
If there is a flu like viral illness, ASA weill leave them prone to Reyes Syndrome
What does it mean that ASA can be ototoxic
impacts 8th cranial nerve and too much is toxic to the ears
What is typical dosage for ASA in adults?
81 mg daily or 325 PO once
What is an important prototype drug that is non-antiflammatory analgesic, non opioid that is grouped with anti inflammatories and NSAIDS
acetaminophen (Tylenol, Tempra)
acetaminophen (Tylenol, Tempra)
a non anti inflammatory and non opioid analgesic - it can be used for its ANTIPYRETIC and ANALGESIC effects (same as Aspirin but without the anti inflammation)
acetaminophen is similar in use to ___ but what sets them apart
it is similar to NSAIDS but has NO anti inflammatory effects and NO effect on platelet aggregation
So it is good for bringing down mild to moderate pain and bringing fever down without bleeding
What is the action of acetaminophen
uncertain but it has both central and peripheral action - the central action is more important in this case compared to peripheral because it acts centrally more on perception of pain as compared to ASA
ADRs of Acetaminophen
Surprisingly free of ADRs at therapeutic doses (less or equal to 4g/day)
Large doses are extremely toxic to the liver - gets press because of liver failure
Chronic use can cause kidney damage (every day)
Many drugs have acetaminophen in it so keep that in mind when taking drugs to prevent overdose
____ is often used in similar instances with aspiring, but has fewer SE and now has an IV formulation (Ofirmev)
acetaminophen
What is the antidote to acetaminophen
acetylcysteine (Mucomyst)
sulforous compound that is a liquid and smells like rotten eggs- needs to be given cont. in precise intervals
Given with 8 hours of ingestion - 3 bags first over 1 hour, second over 4 hours, and third over 16 hours
What is important to know about Tylenol no 1-4
This is the brand name a company uses to show combinations of tylenol with codeine
Combination drugs containing acetaminophen have what suffix
-CET
ex: Percocet, Roxicet, etc
acetaminophen can be toxic to both ___ and ___
liver and kidneys
Other than ASA, what are other important NSAID prototype drugs to know
indomethacin (Indocin)
Ibuprofen (motrin, advil)
celecoxib (Celebrex)
ketorolac
What is the prototype NSAID that is an indole analog
indomethacin (Indocin)
What is the action for indomethacin (Indocin)
potent inhibitor of prostaglandin synthesis
ADRs of Indomethacin (Indocin)
GI (like most NSAIDS) - anorexia, NV, peptic ulcer, and hemorrhage
Headache
Dizziness
Tinnitus
Skin rash
Edema
Rarely - Bone marrow depression
Aggravates psych disturbances, parkinsons, and epilepsy
OCULAR CHANGES (retinal and corneal)
What is the unique side effect of indomethacin as compared to other NSAIDS
the headache - it is a distinct frontal headache (can be severe)
When is indomethacin given instead of ASA or a different NSAID
only in specific inflammatory conditions - not given for HA, pain, fever as a replacement to ASA or acetaminophen - but shares some mechanisms with the 2