NSAIDs

Question 1

Non selective COX inhibitors

Answer 1

1-Salicylic acid derivatives
2- Acetic acid derivatives
3- propionic acid derivatives:
4- Fenamic acid derivatives
5- Oxicams 6- Pyrazolon derivatives
7- Diclofenac

Question 2

Selective COX-3

Answer 2

paracetamol

Question 3

Absorption

Answer 3

orally
•Better from the stomach but more from small intestine

Question 4

Distribution

Answer 4

All over the body, pass BBB, PB and highly bound to plasma proteins

Question 5

Metabolism

Answer 5

Liver

Question 6

Excretion

Answer 6

mainely in urine
•25% excreted unchanged in urine

Question 7

Mechanism of action:

Answer 7

irreversible inhibition of non-selective COX enzyme

Question 8

CNS action

Answer 8

Analgesic: centrally by increasing pain threshold.
B- Antipyretic: inhibit synthesis of PGs induced by IL1, IL6 & TNF that released by bacterial toxins → resetting of HRC → Heat loss by:
*Mobilization of fluids from tissues to plasma
*Increase sweating → heat loss by evaporation

Question 9

2 anti-inflammatory

Answer 9

PGs synthesis
2- ↓ Kallekrein enz. → ↓ bradykinin → ↓ pain
3- ↓ Hyaluronidase enz. → ↓ capillary permeability →↓ swelling & edema.
4- ↓ Fibrinolysins & tissue damaging enz.
5- ↓ migration of polymorphs & macrophages to inflammatory sites.
6- Stabilization of lysosomes→ ↓ release of proteolytic enz

Question 10

CVS action

Answer 10

Therapeutic dose: no effect
Toxic dose : VD & hypotension

Question 11

Respiration & acid base balance

Answer 11

Small dose: no effect
•Large dose:
In adult: respiratory alkalosis due to ↑CO2 wash
In children: metabolic acidosis may be due to:
♣ Dissociation of salicylate to salicylic acid
♣ Impaired CHO metabolism → accumulation of pyruvic acid & lactic acid

Question 12

GIT & liver action

Answer 12

Hyperacidity, GIT ulceration & bleeding
● Nausea and vomiting
● Increase water in bile( hydrochloretic).

Question 13

Uric acid action

Answer 13

Small dose : worse gout
Large dose: treat gout

Question 14

Blood action

Answer 14

Decrease Platelet aggregation
•Haemolysis ( idiosyncracy) in G-6-PD deficiency.

Question 15

Local uses

Answer 15

1. Antiseptic: Salicylic acid + Talcum powder
   2.Antifungal: Salicylic acid + Benzoic acid
   3.Keratolytic
   4.counterirritant.: methyl salicylate

Question 16

Systematic uses

Answer 16

1.Analgesic, antipyretic, anti-inflammatory.
2- uricosuric
3- Antiplatletes
4- chronic use may ↓ Cancer colon

Question 17

Contraindication

Answer 17

1-Allergy
2- Idiosyncrcy
3- Bronchial asthma
4- Peptic ulcer
5- Gout (small dose)
6- Infants & children < 6 years

Question 18

Side effects( ashgar el tin)

Answer 18

1-Acute toxicity
2-Sallicylism
3 - Headache, hypoprothrombinemia &e bleeding
4- GIT irritation ( ulcers)
5-Allergy
6-Rey Syndromelin children <6 years) = fatal hepatic injury and encephalopathy in viral infections
7- Teratogenicity , Tinnitus (ringing ear)
8- Idiosyncrasy (G-6-pd) defiency)
9-Nephrotoxicity

Question 19

What does phospholipase do ?

Answer 19

Transfer steroids into arachidonic acid

Question 20

What does five lipoxygenase do?

Answer 20

Transfer arachidonic acid into leukotrine