NSAIDS pt.1 Flashcards
(24 cards)
What are antipyretic analgesics?
Analgesic, anti-inflammatory, lower body temperature to normal
These are primarily NSAIDs.
What is the mechanism of action of antipyretic analgesics?
Inhibition of COX enzyme synthesis of prostaglandins (PGs)
COX stands for cyclo-oxygenase.
How does Aspirin inhibit the COX enzyme?
Causes irreversible inhibition of COX enzyme by acetylation
Other NSAIDs cause reversible inhibition.
What are the three types of COX enzymes?
- COX1: Constitutive in most tissues
- COX2: Induced by inflammation
- COX3: Present in the CNS
What is the function of COX1?
Physiological protection of the stomach and regulation of renal blood flow and sodium excretion
Inhibition of COX1 can lead to unwanted effects.
What triggers the induction of COX2?
Inflammation, pathological infection, toxins, IL-1, and TNF
COX2 increases prostaglandins, leading to inflammation.
What are the effects of COX enzyme induction in the CNS?
- Hypothalamus → Fever
- Thalamus → Pain
What happens in the periphery due to COX induction?
- Sensitization of nociceptors to histamine, bradykinin, and serotonin
- Potentiation of the effect of these substances leading to vasodilation, redness, and edema
What are the classifications of NSAIDs?
- Non-selective COX inhibitors
- Selective COX2 inhibitors
- Selective COX3 inhibitors
Name an example of a selective COX2 inhibitor.
Celecoxib
Dosage is typically 100-200 mg.
What actions does salicylic acid have locally?
- Keratolytic in corns and warts
- Antifungal in Tinea of skin
- Antiseptic in hyperhidrosis
What are the systemic actions of sodium salicylate?
- Analgesic
- Antipyretic
- Anti-inflammatory and anti-rheumatic action
What are the possible gastrointestinal side effects of large doses of NSAIDs?
Gastric irritation, nausea, and vomiting
What is the effect of small doses of NSAIDs on uric acid levels?
Increases uric acid level, leading to hyperuricemia
This can worsen gout.
What is the effect of large doses of NSAIDs on uric acid levels?
Decreases uric acid level, acting as uricosuric to treat gout
What are the common uses of salicylic acid?
- Keratolytic
- Fungistatic
- Antiseptic
What are the systemic uses of NSAIDs?
- Analgesic for mild superficial pain
- Antipyretic in fever
- Treatment for common cold
- Prophylaxis of thromboembolic diseases
What are the uses of Acetaminophen (Paracetamol)?
- Analgesic
- Antipyretic
- Suitable for patients who cannot tolerate aspirin
What is a significant side effect of toxic doses of Acetaminophen?
Hepatotoxicity and nephrotoxicity
Toxic dose is >10g in adults and >4g in children.
What is the management for Acetaminophen overdose?
IV N-acetylcysteine
What are common allergy reactions to NSAIDs?
- Rash
- Urticaria
- Angioedema
What is Reye’s syndrome?
A serious condition that can occur in children taking aspirin during viral infections
It is associated with cardiac septal defects.
What renal side effect can occur from NSAIDs?
Analgesic nephropathy
