Clinical Pharmacology and Toxicology

Question 1

What acid base balance is associated with salicylate OD?

Answer 1

Mixed respiratory alkalosis and metabolic acidosis

Question 2

What are the features of salicylate OD?

Answer 2

• Pyrexia
• Sweating
• Hyperventilation
• Nausea
• Tinnitus
• seizures
• coma

Question 3

What is the management of salicylate OD?

Answer 3

• ABCDE
• Activated charcoal
• Urine alkalinasation with Na Bicarb
• Haemodialysis

Question 4

What are the indication for haemodialysis in salicylate OD?

Answer 4

• Serum concentration >700
• Pulmonary oedema
• seizures
• coma
• acidosis resistant to treatment
• AKI

Question 5

What is the MoA of Rifampicin?

Answer 5

Inhibits RNA synthesis

Question 6

What is the MoA of Flecanide?

Answer 6

Sodium channel blocker
Class 1c antiarhythmic

Question 7

What is the MoA of Quinolones (ciprofloxacin)?

Answer 7

Inhibits DNA synthesis

Question 8

What is the MoA of Digoxin?

Answer 8

Inhibition of Na/K+ ATPase pump

Question 9

What is the KCH criteria for liver transplant?

Answer 9

• pH <7.3
• Creatine >300
• PT >100
• grade III/IV encephalopathy

Question 10

What are the features of cyanide poisoning?

Answer 10

• Brick red skin
• Smell of bitter almonds
• Confusion
• Hypoxia, hypotension and headache
• Chronic: ataxia, peripheral neuropathy, dermatitis

Question 11

What is the pathophysiology of cyanide poisoning?

Answer 11

Inhibits the enzyme cytochrome C oxidase –> cessation of mitochondrial electron transfer chain

Question 12

What type of reaction takes place in Phase I drug metabolism?

Answer 12

• Hydrolysis
• Oxidation
• Reduction

Question 13

What type of reaction takes place in Phase II drug metabolism?

Answer 13

Conjugation

Question 14

What is zero order kinetics?

Answer 14

Metabolic pathways become saturated

Question 15

What drugs exhibit zero order kinetics?

Answer 15

Salicylates
Heparin
Ethanol
Phenytoin

Question 16

What is first pass metabolism?

Answer 16

when majority of the drug is metabolised by the liver before reaching systemic circulation
Larger doses of the drug is required

Question 17

Which drugs are affected by acetylator status?

Answer 17

Sulfasalazine
Hydralazine
Isoniazid
Procainamide
Dapsone

Question 18

What is the mechanism behind Heparin Induced Thrombocytopenia?

Answer 18

Antibodies directed against PF4 and Heparin

Question 19

What is the mechanism of LMWH?

Answer 19

Activates antithrombin III –> inhibits factor Xa

Question 20

What is the MoA of unfractionated heparin?

Answer 20

Inhibits thrombin, Xa, IXa, XIa and XIIa

Question 21

What are the adverse effects of heparin?

Answer 21

thrombocytopenia
bleeding
fractures
osteoporosis
hyperkalaemia

Question 22

What acid base balance is seen in Ethylene glycol poisoning?

Answer 22

Metabolic acidosis with high anion gap and high osmolar gap

Question 23

What is the MoA of Trastuzumab?

Answer 23

Her2/neu receptor antagonist

Question 24

What is the MoA of Rutuximab?

Answer 24

anti-CD20
used in Non-hodgkin’s lymphoma and RA

Question 25

What is the MoA of infliximab?

Answer 25

anti-TNF used in Crohn's and RA

Question 26

What is the MoA of Alemtuzumab?

Answer 26

anti-CD52

Question 27

What is the MoA Cetuximab?

Answer 27

Epidermal growth factor receptor antagonist

Question 28

What is the MoA of Tamoxifen?

Answer 28

Selective Oestrogen Receptor Modulator oestrogen receptor antagonist and partial agonist

Question 29

What is the treatment for TCA OD presenting within 1 hr?

Answer 29

Activated charcoal