Pharmacology

Question 1

Which type of diuretic can be useful in preventing the formation of calcium stones by causing increased Ca²⁺ reabsorption?

Answer 1

Thiazides —> decrease urine Ca²⁺ excretion

Question 2

Which drug can be used to decrease the risk of uric acid kidney stones?

Answer 2

Acetazolamide

Question 3

The SERM, Tamoxifen, is a prodrug used in breast cancer treatment that metabolized by what CYP and to what active metabolite?

Answer 3

CYP2D —> active metabolite, endoxifen

Question 4

Which 3 drugs can be used for venous thromboembolism and atrial fibrillation in pt’s with heparin-induced thrombocytopenia?

Answer 4

• Bivalirudin
• Argatroban
• Dabigatran

*Direct thrombin inhibitors; used when heparin is BAD for the pt

Question 5

What is the MOA of cyclosporine?

Answer 5

Binds cyclophilin in lymphocytes and inhibits calcineurin –> ↓ IL-2

Question 6

What is the MOA of Tacrolimus?

Answer 6

Binds FK506-binding protein and Inhibits IL-2 through a calcineurin-dependent mechanism

Question 7

What are the most common mechanisms of aminoglycoside resistance?

Answer 7

Antibiotic-modifying enzymes adding chemical groups i.e., acetyl ,adenyl, phosphate

Question 8

What is the MOA and use for Flutamide?

Answer 8

• Nonsteroid anti-androgen that competitively inhibits testosterone receptors
• Used in tx of prostate cancer –> improves sx’s of bone pain and urinary obstruction

Question 9

List the 4 preferred agents used for bipolar maintenance tx?

Answer 9

• Lithium
• Anticonvulsants: Valproate and Lamotrigine
• Quetiapine (2nd gen. antipsychotic)

Question 10

List 5 medication classes which prolong the QT and can induce torsades.

Answer 10

• Macrolides
• Fluoroquinolones
• Anti-psychotics: haloperidol and risperidone
• Antiemetics: ondansetron and metoclopramide
• Azoles

Question 11

What is phenylephrine and what is its effect on peripheral vascular resistance, systolic BP, pulse pressure, and HR?

Answer 11

• Selective alpha-1 AR agonist
• ↑ PVR and ↑ systolic BP
• ↓ pulse pressure and ↓ HR

Question 12

What is the most frequently used agent for the chemoprophylaxis of meningococcal disease?

Answer 12

Rifampin

Question 13

Which 3 classes of drugs act on the ciliary epithelium to decrease aqueous humor secretion and can be used for glaucoma?

Answer 13

• Non-selective beta-blockers: Timolol
• Alpha-2 AR agonists
• Carbonic anhydrase inhibitors: Acetazolamide

Question 14

What is the MOA of administering Amyl Nitrite to pt with Cyanide poisoning?

Answer 14

• Oxidizes Fe²⁺ –> Fe³⁺ generating methemoglobin
• Methemoglobin has a high affinity for cyanide, freeing it from cytochrome oxidase and limiting its toxic effects

Question 15

What are 2 monoclonal antibodies against PD-1 and which is against PD-L1?

Answer 15

• Pembrolizumab and Nivolumab are against PD-1
• Atezolizumab is against PD-L1

*Used for advanced melanoma, some lung cancer, and RCC

Question 16

How can mycobacteria develop resistance to both isoniazid and ethambutol?

Answer 16

• Isoniazid: decreased activity of bacterial catalase-peroxidase
• Ethambutol: increased activity of enzymes involved in cell wall polysaccharide synthesis

Question 17

Digoxin slows ventricular rate during AF primarily by causing what?

Answer 17

• Increased parasympathetic tone –> inhibition of the AV nodal conduction
• Used in HF due to positive inotropic effect; accomplished through inhibition of Na/K-ATPase pump

Question 18

What is the MOA of the stimulant drugs (methylphenidate and amphetamines) used to treat ADHD?

Answer 18

Blocking NE and dopamine re-uptake at synapses in the prefrontal cortex

Question 19

Clozapine is a 2nd-gen. antipsychotic that is used for what?

Answer 19

Treatment-_refractory_ Schizophrenia

Question 20

Which 2 second-gen. antipsychotics carry the greatest risk of metabolic syndrome and require pt’s to undergo routine monitoring of weigh, waist circumference, BP, fasting glucose and lipid profiles?

Answer 20

Olanzapine and Clozapine

Question 21

Which laboratory test should be obtained before starting patient on Metformin?

Answer 21

• Serum creatinine level to evaluate to estimate GFR and evaluate kidney function
• Patients with recent IV contrast administration may have suppressed renal function

Question 22

Which 2 medications require routine thyroid function tests?

Answer 22

Lithium and Amiodarone

Question 23

Which 2 antiseizure meds work by blocking Na⁺ channels?

Answer 23

Phenytoin and Carbamazepine

Question 24

What is the 1st line tx for absence seizures and what is the MOA?

Answer 24

• Ethosuximide
• Blocks T-type Ca²⁺ channels in thalamic neurons

Question 25

Which antiseizure med works by blocking Na⁺ channels and increasing GABA levels?

Answer 25

**Valproic acid**

Question 26

What are 2 important AE's associated with Carbamazepine?

Answer 26

- **Bone marrow suppression** --\> anemia, agranulocytosis, and thrombocytopenia - **SIADH** ---\> hyponatremia

Question 27

What is th drug of choice for tx of Bulimia Nervosa?

Answer 27

**Fluoxetine** (SSRI)

Question 28

Why are ACEI's and ARBs containdicated during pregnancy?

Answer 28

- Leads to _low_ levels of **angiotensin II**, which is necessary for **_fetal renal_ development** - This leads to **Potter sequence** due to **oligohydramnios** --\> **pulmonary hypoplasia** and **skeletal defects**

Question 29

What are 4 characteristics of a drug which would cause it to be trapped in the plasma compartment resulting in a low V_d (3-5L)?

Answer 29

- **High molecular weight** - **High plasma protein binding** - **High charge** - **Hydrophilicity**

Question 30

What can be a potential limiting factor when starting a patient on an ACE inhibitor?

Answer 30

- **First-dose HYPOtension** - Most likely in pt's w/ **high renin** activity, such as those w/ **volume depletion** (i.e., from diuretic use) or **heart failure**

Question 31

What are the 2 positive effects of using the PDE-3 enzyme inhibitor, Milrinone for heart failure?

Answer 31

- In **cardiomyocytes**, intracellular Ca²⁺ is **increased** --\> increases **contractility** (positive inotropy), improving **SV** and **cardiac output** - In **vascular smooth m.**, increases uptake of **Ca²⁺** by the **SR** = **relaxation** and **vasodilation** = decreases **preload** and **afterload**

Question 32

What are the drugs of choice for treating heparin-induced thrombocytopenia (HIT)?

Answer 32

**Direct thrombin inhibitors** = Hirudin, Lepirudin, and Argatroban

Question 33

Which 2 drugs are commonly used to tx spasticity secondary to both brain and spinal cord disease, including MS; what are their MOA's?

Answer 33

- **Baclofen**: an **_agonist_** at the **GABA-B receptor** - **Tizanidine**: an **_agonist_** at the **alpha-2 AR**

Question 34

Which 3 anticonvulsants can be used as mood stabilizers in tx of bipolar disorder?

Answer 34

- **Valproate** - **Lamotrigine** - **Carbamazepine**

Question 35

Which AE's are associated with the first-line tx for CMV colitis and retinitis, Gangciclovir?

Answer 35

**Neutropenia**, **thrombocytopenia**, and **anemia**

Question 36

What is the MOA of the non-benzodiazepine hypnotic agents, Zolpidem, Zaleplon, and Eszopiclone?

Answer 36

_Agonist_ at **GABA_A receptor** at the **benzodiazepine receptor site**

Question 37

What is the MOA of Cromolyn and Nedocromil?

Answer 37

**_Inhibit_ mast cell degranulation** and prevent release of _preformed_ mediators

Question 38

Methylation is an important drug biotransformation method to consider when prescribing drugs such as?

Answer 38

**Azathioprine** and **6-mercaptopurine**

Question 39

Which drug is as effective as aspirin for prevention of cardiovascular events and should be used in pt's with an aspirin allergey; what's the MOA?

Answer 39

**Clopidogrel**: irreversibly blocks the **P2Y₁₂ component** of **ADP receptors** on the platelet surface and _prevents_ **aggregation**

Question 40

Which 5 drugs are commonly implicated in drug-induced lupus?

Answer 40

- **Hyrdralazine** - **Procainamide** - **Isoniazid** - **Minocycline** - **Quinidine**

Question 41

Why do ACE inhibitors cause an increase in creatinine levels within the first few days of starting tx; who might this cause serious problems in?

Answer 41

- Due to _decreased_ **angiotensin II** --\> _decreased_ **efferent** arteriole constriction - Pt's with **bilateral renal artery stenosis** (heavily dependent on angiotensin II to maintain GFR) can experience a precipitous fall in GFR and develop **acute renal failure**

Question 42

After stabilization, long term use of which medications have been shown to improve survival in pt's with heart failure due to LV systolic dysfunction (decompensated HF)?

Answer 42

- **Beta-blockers** i.e., Carvedilol or Metoprolol - **ACE inhibitors** - **ARBs** - **Aldosterone antagonists**: Spironolactone and Eplerenone

Question 43

What are the 3 aromatase inhibitors which can be used to slow the progression of ER-positive tumors?

Answer 43

- **Anastrozole** - **Letrozole** - **Exemestane**

Question 44

Sinus bradycardia is the most common arrhythmia in those with inferior wall MI, which drug should be given IV to correct this?

Answer 44

**Atopine**: counteracts the enhanced vagal tone to _increase_ **HR**

Question 45

How can mu-opioid agonists such as morphine cause biliary colic?

Answer 45

Cause **contraction** of the **SMOOTH M. cells** in the **sphincter of Oddi**, leading to **spasm** and _increase_ in **common bile duct pressures**

Question 46

Which agents used for skeletal muscle relaxation during surgery are pt's with Myasthenia Gravis extremely sensitive to and which are they often resistant to?

Answer 46

- Extremely **_sensitive_** to **NON-depolarizing** agents: **Vecuronium** or **Rocuronium** = competitive **_antagonist_** at **nAChRs** - Often **_resistant_** to **depolarizing agents** --\> **Succinylcholine** = competitive **_agonist_** at **nAChRs**

Question 47

What are the 4 broad spectrum anti-seizure drugs which can be used as first-line tx of generalized tonic-clonic and myoclonic seizures?

Answer 47

- **Valproic acid:** block Na+ channels and increases GABA - **Levetiracetam****:** modulates GABA and glutamate release - **Topiramate** and **Lamotrigine**: increases Na+ channel inactivation

Question 48

What is the MOA of Cilostazol and Dipyridamole and what are they used for; what are the AE's?

Answer 48

- Reduce platelet activation by _inhibiting_ platelet **PDE**, which normally breaks down **cAMP** and also act as _direct_ arterial **vasodilators** - Used to decrease **claudication** sx's in pt's with **peripheral artery disease** - **AE's:** facial flushing and abdominal pain

Question 49

Which drug classes are effective in tx OCD?

Answer 49

- **SSRIs** = tx of choice - **TCA's** use **clomipramine** for cases unresponsive to SSRIs