Analgesics Flashcards
Pain
Pain is a PROTECTIVE mechanism
It is based on :
DURATION and
ONSET
Pain in dentistry based on INFLAMMATION
SOMATIC : caused by tissue damage the pain receptors NOCIOCEPTORS, cause it
Ex: periodontal, alveolar, or mucosal pain
VISCERAL pain : caused by DEEPER tissues
Ex: pulpal pain, thoracic area, stomach pain
Acute pain
4
usually seen in Dentistry-lasts 1 to 7 days
Comes on SUDDENLY and has a LIMITED duration
Caused by damage to tissue, such as bone muscle or organs
Onset is often accompanied by ANXIETY or EMOTIONAL DISTRESS
Chronic pain
Last 1-2 weeks
More related to MEDICAL CONDITIONS and long-term illnesses, such as osteoarthritis
It last LONGER than acute pain, and it’s somewhat RESISTANT to medical treatment
Very often attributable to nerve damage
IMPORTANT:
It has SOMATOSENSORY and PSYCHOSOCIAL impacts
IMPORTANT:
In Both acute and chronic pain , perception involves the SAME regions of the brain. That is the CNS.
Dimensions of pain
SENSORY : perception of the :
1.location,
2.intensity(mild, moderate, and severe )and
3.quality of pain(stabbing, lancinating, dull, sharp)
AFFECTIVE : reference to the
UNPLEASANTNESS inherent to the pain and the EMOTIONS related to future implications
Points to consider in use of painkillers (analgesics)
- Eliminate the source of pain if possible
2.Individualized regimens
3.OPTIMIZE dose and frequency before switching
4.Maximize the non-opioid before adding the opioid
- Consider LOADING and preoperative dose for nonsteroidal anti-inflammatory drugs(NSAIDS)
6.AVOID chronic use of analgesics
- REDUCE the dose in OLDER individuals
Criteria when selecting an analgesic agent
- Severity of the pain.: mild, moderate,severe- MOST IMPORTANT
- age of the patient.: infant child, adult, elderly
- Concurrent medication’s.: other medication’s being taken
- Pregnancy as all drugs, a pregnant woman, take skin, cross the placenta and enter the foetal circulation.
- Medical conditions of the patient including pregnancy.
Pain threshold
LOWEST level of the pain a person will detect
For pain severity
WONG BAKER rating scale
WONG BAKER faces pain, rating scale
It has 2 groups
1. mild to moderate :
0-no hurts
2- hurts little bit
4-hurts little more
- Moderate to severe:
6-hurts even more
8-hurts whole lot
10-hertz worst
Painkillers prescribed on pain severity
1-mild to moderate-DOC-acetaminophen
- Moderate to severe.DOC-NSAIDs, other than ASA aspirin
- If NSAIDs are not enough or contraindicated, we give opioids.
Acetaminophen
Safest drug
EVEN if the patient has cirrhosis or liver, disease or chronic alcoholism
Does not affect Cox 1 and Cox 2 so it does NOT have any ANTI-INFLAMMATORY effect
Acetaminophen mechanism of action
INHIBITS COX-3
Inhibition of central prostaglandin formation,
inhibits central CNS cyclooxygenase COX-3
Actions of acetaminophen
ANALGESIC for mild to moderate pain
ANTIPYRETIC
NO anti-inflammatory action
It does not affect
1. inflammatory response ,
2.platelet functions or the coagulation pathways.
3It has no effect on bleeding time.
Analgesic of choice in elderly and children
Acetaminophen
Acetaminophen, acute overdose
Most famous side effect is HEPATOTOXICITY, and finally HEPATIC NECROSIS
Long-term use of acetaminophen may lead to RENAL toxicity
Maximum recommended dose of acetaminophen in adults
4000 mg per day or 4 g per day
Maximum recommended dose of acetaminophen for kids that is less than 12 years of age
It’s based on body WEIGHT but about 2.6 g per day.
If you don’t have any patient feet then MRD is equal to 2.6 g per day.
Acetaminophen poisoning antidote
N-acetylcysteine, NAC
It is the ONLY analgesic other than opioids that has an antidote
indications of acetaminophen
It is a drug of choice for any patient for mild to moderate pain
Best NSAID to Control dental pain after adjustment of orthodontic appliance
Acetaminophen
Hepatotoxicity risk
Chronic consumption of 3 or more drinks per day
may increase the risk of hepatotoxicity
because of
increased P-4 50 mediated conversion of acetaminophen
to reactive, hepatotoxic metabolites
Mild to moderate pain
Been related to
Dry socket
Simple extraction
Root planning
Reversible pulpitis
Moderate to severe pain
Irreversible pulpitis
Extensive surgeries
Acute apical abscess
Necrotizing periodontitis
Gingivitis
Acetaminophen, side effect
Causes Methhaemoglobinaemia in high doses
NSAIDs action
Analgesic
Antipyretic
Anti-inflammatory
Antiplatelet (sometimes )
Aspirin— mechanism of action
It inactivates both cyclooxygenase 1 and 2 (COX-1 & COX-2)
Actions of aspirin
Analgesic
Antipyretic
Anti-inflammatory
Irreversible platelet inhibitor ( by preventing production of thromboxane A2)
Prolonged bleeding
Dose of ASA for prophylaxis of myocardial infarction
80 mg
Is used for its ANTI PLATELETS for prophylaxis of myocardial infarction in a patient with a history of UNSTABLE ANGINA PECTORIS or with the history of myocardial infarction
It is also used to prescribe to prevent HEART ATTACK and transient ischaemia attack TIA
Antiplatelet action
Inhibit platelet aggregation
Anticoagulant
Affect the end result of the coagulation cascade that is Fibrin
Warfarin
Heparin
Factor 10 A
Dabigatran example rivaroxaban
The recommended ASA dose during a heart attack
160 mg to 162 mg chewable or crushed
Analgesic and anti-pyretic of aspirin
325 to 650 mg
used for pain but it is not the best choice
325 to 650 mg of Aspirin dose is used where else
And arthritis as it is a very good anti-inflammatory
The antithrombotic effective of Aspirin may be compromised by
Ibuprofen
The principal site for salicylate metabolism
And excretion
Liver
Excretion occurs, mainly via kidney
How does the antithrombotic effective aspirin be compromised by ibuprofen?
Aspirin 81 mg & ibuprofen ——-do interact
Ibuprofen can interfere with antithrombotic affect of aspirin, but up to four days is OK
Aspirin toxicity
Acute
Initial symptoms are
1. Respiratory alkalosis with hypercapnia and tachypnea.
2. Nausea and vomiting.
3. Hypokalemia.
4. tinnitus
5. Headache.
6. Dizziness, and confusion.
7. Dehydration.
8. Hyperthermia.
9. Hyperactivity.
10. Haematologic abnormalities.
It can finally progress to coma and respiratory collapse
