6. ASPIRIN
It is a salicylic acid derivative.
Mechanism of action:
It is a weak acid that irreversibly acetylates COX-I and COX-II
Pharmacological effects:
1-Analgesic effect:
It inhibits COX and ↓PGE2 synthesis
It ↓ sensation of pain by acting on CNS
7. ASPIRIN
Pharmacological effects:
2-Antipyretic action:
It ↓ temperature by blocking synthesis of PGE2 in hypothalamus
3-Action on platelets:
It prevents synthesis of TXA2 by inhibiting COX-I and this prevents the
platelet aggregation.
4- Anti-inflammatory effect:
At high dose aspirin produces anti-inflammatory effect by inhibiting
COX enzyme
8. THERAPEUTIC INDICATIONS OF ASPIRIN
Angina pectoris
Unstable angina
Myocardial infarction
Secondary prevention after MI
Following endovascular surgery
Atrial fibrillation
Transient ischemic attacks (TIAs)
9. THERAPEUTIC INDICATIONS OF NSAIDs
1. Analgesic:
Headache, neuralgia, myalgia, post-operative and dental procedures,
dysmenorrhea
2. Antipyretic in febrile conditions
3. Anti-inflammatory
Rheumatoid arthritis
Ankylosing spondylitis
4. Other effects:
Prevention of Eclampsia and Preeclampsia
Lower incidence of colon cancer
10. ADVERSE EFFECTS OF NSAIDs
1. Headaches, tinnitus, dizziness,
2. Fluid retention, hypertension, edema,
3. Abdominal pain, dyspepsia, nausea, vomiting, ulcers or bleeding.
4. Thrombocytopenia, neutropenia, or even aplastic anemia
5. Abnormal LFTs and liver failure
6. Asthma
7. Rashes, all types, pruritus
8. Renal insufficiency, renal failure
9. Hyperkalemia, and proteinuria
5/29/2021 ANS 10
11. PARACETAMOL (ACETAMINOPHEN )
Active metabolite of phenacetin
Mechanism of action:
It inhibits COX🡪 ↓PGs synthesis in CNS
Pharmacological effects:
1-Analgesic effect
2-Antipyretic effect
12. PARACETAMOL (ACETAMINOPHEN )
Uses:
1-As analgesic and antipyretic in patients with GIT ulcers/bleeding
2-As antipyretic in children with viral infection
3-Gout
Adverse effects:
1-Minor allergies, skin rash
2-Hepatic necrosis (life-threatening condition)
3-Alcoholics, viral hepatitis, hepatic disease🡪↑ risk of acetaminophen toxicity
4-Renal tubular necrosis may occur
T/M of Toxicity
Anti-dote: N-Acetyl cysteine