Pharmacology

Question 1

MOA of Pilocarpine? (Indication: Glaucoma)

Answer 1

Stimulation of muscarinic cholinergic receptors to increase aqueous humour outflow resulting in ciliary contraction (contraction of the iris), which will increase aqueous humour outflow, miosis, and accommodation.

Question 2

MOA Latanoprost? (Indication Glaucoma)

Answer 2

Increasing uveoscleral outflow of aqueous humour by activating prostaglandin receptors

Question 3

MOA: Dorzolamide? (Indication glaucoma)

Answer 3

Reduce the production of aqueous humour by inhibition of carbonic anhydrase

Question 4

Mechanism of Aspirin?

Answer 4

irreversibly inhibits cyclooxygenase-1 (COX-1) enzyme which inhibits the production of thromboxane A2

Question 5

MOA of Ciclosporin and Tacrolimus?

Answer 5

inhibit calcineurin thus decreasing IL-2

Question 6

MOA Fleclanide?

Answer 6

potent sodium channel blocker (specifically the Nav1.5 sodium channels

Question 7

MOA of LMWH?

Answer 7

Low-molecular weight heparin activates antithrombin III. Forms a complex that inhibits factor Xa

Question 8

Digoxin:
MOI?
Indications?
Notable SEs?

Answer 8

inhibition of the Na+/K+ ATPase pump (Slows rate via AV and positive inotropic affect)
Rate control, symptoms in HF (specific indications)
SE = arrythmias, confusion, yellow/green vision, gynaecomastia

Question 9

INDUCERS of cytochrome P450 (PC BRASS)

Answer 9

Phenytoin, Carbamazepine, Barbiturates, Rifampicin, Alcohol (chronic), Sulphonylurea, Smoking,

Question 10

Inhibitors of cytochrome P450 (CRACK AMIGOS)

Answer 10

Cimetidine, Ritonavir, Amiodarone, Ciprofloxacilin, Ketoconazole, Acute alcohol use, Macrolides, Isoniazid, Grapefruit juice, Omeprazole, Sulfonamides

Question 11

MOI Pilocarpine?

Answer 11

Muscuranic Agonist

Question 12

Pharmacokinetics: what is phase 1 metabolism?

Answer 12

oxidation - Addition of oxygen or removal of hydrogen atom
reduction - Gain of electrons or hydrogen atoms
hydrolysis - add water to a drug molecule resulting in its breakdown to more polarised forms

Question 13

Pharmacokinetics: what is phase 2 metabolism? (Conjugation)

Answer 13

Products are typically inactive and excreted in urine or bile

Question 14

What is first past metabolism?

Answer 14

a phenomenon where the concentration of a drug is greatly reduced before it reaches the systemic circulation due to hepatic metabolism. As a consequence much larger doses are need orally than if given by other routes

Question 15

What is zero order kinetics?

Answer 15

describes metabolism which is independent of the concentration of the reactant. This is due to metabolic pathways becoming saturated resulting in a constant amount of drug being eliminated per unit time

Question 16

T/F 50% UK population are deficient in Acetylator status which affects metabolism of key drugs?

Answer 16

True
Drugs affected:
isoniazid
procainamide
hydralazine
dapsone
sulfasalazine

Question 17

Mnemonic for zero order kinetics:
Zero Alcohol Is Allowed

Answer 17

Police (Phenytoin)
Stop (Salicylate)
Heavy (Heparin)
Drinkers (Ethanol)

Question 18

Mnemonic for drugs affected by acetylator status:
SHIPpeD

Answer 18

Sulfosalazine. Hydralazine. Isoniazid. Procainamide. Dapsone

Question 19

Mnemonic for first past metabolism drugs:
Nitrates Have A Very Large Pre Systemic Intake

Answer 19

Nitrates, hydrocortisone, aspirin, verapamil, lignocaine, propranolol, iSoSorbide dinitrate, Isoprenaline, Testosterone

Question 20

MOA of Quinolones (e.g. ciprofloxacilin)

Answer 20

Inhibits DNA synthesis by inhibiting topoisomerase

Question 21

MOA Macrolides (e.g. Clarithromycin)

Answer 21

Binds to 50S subunit, inhibiting translocation (movement of tRNA from acceptor site to peptidyl site)

Question 22

MOA of tetracyclines (e.g. doxycycline)

Answer 22

Binds to 30S subunit blocking binding of aminoacyl-tRNA

Question 23

MOA Aminoglycosides? (Gentamicin)

Answer 23

Binds to 30S subunit causing misreading of mRNA

Question 24

MOA of Penicilins, cephalosporins, carbapenems?

Answer 24

Inhibit the cross-linking of peptidoglycans in bacterial cell walls

Question 25

MOA Metronidazole?

Answer 25

DNA Damage

Question 26

MOA Sulphonamides, trimethoprim?

Answer 26

Inhibits folic acid formation

Question 27

MOA Rifampicin?

Answer 27

Inhibits RNA synthesis

Question 28

What drug is indicated, when you suspect adrenaline induced ischaemia during local infiltration?

Answer 28

Phentolamine (Competitive a-adrenoreceptor antagonist)

Question 29

MOA Metformin?

Answer 29

activation of the AMP-activated protein kinase (AMPK)

Question 30

Aetiology of heparin induced thrombocytopenia?

Answer 30

Antibodies against complexes of platelet factor 4 (PF4) and heparin

Question 31

Monitoring blood test for: 1) Unrationed Heparin 2) LMWH

Answer 31

1) APTT 2) Anti-factor Xa

Question 32

Infliximab: Indication: Target:

Answer 32

Crohns TNFa

Question 33

Rituximab Indication: Target:

Answer 33

Non-Hodgkins CD20

Question 34

Daratumumab Indication: Target:

Answer 34

Multiple Myeloma CD38

Question 35

Alemtuzumab Indication: Target:

Answer 35

chronic lymphocytic leukaemia CD52

Question 36

Trastuzumab (more commonly known as Herceptin) Indication: Target:

Answer 36

metastatic breast cancer HER2

Question 37

What is the mechanism of aminoglycoside neprhotoxicity?

Answer 37

Acute tubular necrosis

Question 38

Pathophysiology of paracetamol induced hepatotoxicity?

Answer 38

Paracetamol overdose occurs when glutathione stores run-out leading to an increase in NAPQI (N-acetyl-p-benzoquinone imine)

Question 39

T/F Ciprofloxacilin side effects -> everything is increased (Fluid, BP, K+, Hair, Gums, Glucose)

Answer 39

True

Question 40

How does COCP use affect the incidence of the following cancers: 1) Breast + Cervical 2) Ovarian + Endometrial

Answer 40

1) Increased risk 2) Decreased risk

Question 41

Drugs which can be cleared with Hemodialysis (BLAST)

Answer 41

BARBITURATE Lithium Alcohol (inc methanol, ethylene glycerol) Salicylates Theophyllines

Question 42

MOA of heparin?

Answer 42

Enhances activity of circulating antithrombin

Question 43

1mg of prednisone is equivalent to how much hydrocortisone?

Answer 43

4mg hydrocortisone

Question 44

1mg Dexamethasone is equivalent to Hoe much prednisone?

Answer 44

7mg Prednisolone

Question 45

How do class one anti arrhythmias work?

Answer 45

Inhibit sodium channels -Amiodarone/ Lidocaine/ Phenytoin / Flecainide

Question 46

How do class two anti arrhythmias work?

Answer 46

Beta blockers -propranolol -Esmolol

Question 47

How do class 3 anti arrhythmias work?

Answer 47

Potassium Channel Blocker -Sotalol -Amiodarone

Question 48

How do class 4 anti arrhythmias work?

Answer 48

Calcium channel blocker -Verapamil -Diltiazem

Question 49

How do class 5 anti arrhythmias work?

Answer 49

Unexplained -Adenosine / Digoxin / K+ ions / Mg Ions

Question 50

MOA of furosemide? (lasix)

Answer 50

Inhibiting chloride absorption in the ascending loop of Henle (Lasix = lasts 6 hours)

Question 51

MOA of Bendroflumethaizide?

Answer 51

Inhibiting sodium absorption at the beginning of the DCT

Question 52

What is 'DRESS' syndrome?

Answer 52

Drug reaction with eosinophilia and systemic symptoms -Triad: Extensive skin rash, pyrexia, organ involvement

Question 53

Cyanide Poisoning -Presentation -Signs -Pathophysiology of poisoning -Tx:

Answer 53

-Factory worker rescued from fire (burning plastics) -Headache, bitter smell, red, ashen, hypoxic -Inhibition of cytochrome C Oxidase leading to cessation of mitochondrial electron transfer chain -IV Hydroxocobalamin (Alternatives: inhaled amyl nitrate / IV Sodium thiosulfate)

Question 54

Where is the most common defect implicated in Catecholaminergic polymorphic ventricular tachycardia (VPVT)? -Gene defect -Inheritance pattern

Answer 54

-Ryanodine receptor (RYR2) found on myocardial sarcoplasmic reticulum -Autosomal Dominant

Question 55

Brugada Syndrome -Inheritance pattern -Gene mutation

Answer 55

-Autosomal dominant -SCN5a which encodes the myocardial sodium ion channel protein

Question 56

Congenital Cyanotic heart disease: -Most common at birth -Most common overall

Answer 56

-Transposition of the great arteries -Fallots

Question 57

4 most common congenital acyanotic heart diseases?

Answer 57

-VSD -ASD -PDA -Coarctation of the aorta

Question 58

Patient Ductus Arteriosus -Acyanotic or cyanotic -Where is the abnormal connection -Management

Answer 58

-Acyanotic -Pulmonary trunk and descending aorta -Indomethacin (However, may use prostaglandin E1 to keep open if awaiting surgical repair)