Chapter 2 and Chapter 3 Rx Prep Questions

NSAID (Ibuprofen) Structure

1 aromatic ring with 2 chains off of it

Which drug contains an acidic, carboxyl functional group?

Aspirin (Acetylsalicylic acid) ASA has an acidic, carboxyl functional group

Drug A is a substrate of enzyme X. Drug A is also an inducer of enzyme Y. Drug B is a substrate of enzyme Y. Drug B is also an inhibitor of enzyme X. When these drugs are both administered what will happen to the drug concentrations?

Levels of Drug A will increase and levels of Drug B will decrease.

The somatic nervous system controls voluntary muscle movement by releasing which neurotransmitter?

Acetylcholine PNS has two main divisions - somatic (voluntary) and autonomic (involuntary) For voluntary - ACh acts on the nicotinic receptors in the skeletal muscle.

The PDE inhibitors such as tadalafil cannot be used safely with nitrates. What is most likely to happen if a pharmacist missed this interaction?

Acute drop in BP Nitrate use with PDE5 inhibitors is contraindicated. Use caution with alpha blockers, particularly non-selective agents (primarily doxazosin) which cause more dizziness and orthostasis. Start at the lower dosing range and titrate slowly.

CL is about to get on the waiting list for a kidney transplant. She has a creatinine clearance of 22 mL/min and experiences frequent bouts of hyperkalemia. She cannot use any medicines taht elevate potassium because even small increases in potassium may trigger an arrhythmia. Which medications elevate potassium and would put her at risk?

Aldactone Yasmin Inspra Potassium is renally cleared; severe renal disease causes hyperkalemia by itself, and potassium is cleared by dialysis. Additive potassium accumulation can be due to potassium retaining agents.

A company developed a non-selective beta blocker. What is an expected effect?

Bronchoconstriction Non-selective will act as antagonists to both beta-1 and beta-2 receptors. Beta-1 will decrease cardiac output and heart rate. Beta-2 will cause bronchoconstriction.

CYP 450 enzymes are found in many cells, but are primarily located in the liver and intestine. The majority of drugs are metabolized by CYP 450 enzymes and half of these are metabolized by this enzyme, the primary drug metabolizing enzyme:

CYP 450 3A4 Know the strong inducers and inhibitors for this enzyme

Pt has rx for selegiline. The pharmacist notes that TZ has a diagnosis of depression and parkinsons disease and is currently taking tranylcypromine. What should the pharmacist do?

Call prescriber to discuss major drug interaction Both are MAO inhibitors A 14 day washout period is generally recommended between MAO inhibitors. Using multiple MAOs together increases the risk of serotonin syndrome and/or hypertensive crisis

Many patients occasionally eat grapefruit or drink grapefruit juice. choose the correct statements concerning grapefruit interactions:

Do not eat grapefruit with sandimmune Do not eat grapefruit with tacrolimus Do not eat grapefruit with prograf

A patient is using codeine for pain. She is a CYP 2D6 rapid metabolizer. What would be the effect on the conversion of codeine to morphine by the 2D6 enzyme?

Codeine is a prodrug --> morphine. So by being a rapid metabolizer - the morphine concentration would increase. The use of codeine in breast-feeding women should be avoided because if the woman is a rapid metabolizer of 2D6, the codeine to morphine conversion would increase. Morphine crosses readily into breast milk and the infant could suffer fatal respiratory depression. Contraindicated in children <12

A patient is using digoxin. If he is prescribed the following drug, the digoxin dose will need to be decreased:

Cyclosporine The following drugs increase digoxin levels: quinidine, verapamil, erythromycin, clarithromycin, itraconazole, cyclosporine, propafenone, spironolactone, and a few others. Cyclosporine is both a 3A4 inhibitor and a p-gp inhibitor.

Drug A is a substrate of 2C9 and a potent 3A4 inhibitor. Drug B is a substrate of 2D6 and 1A2 as well as a potent inhibitor of 2C19. Drug C is a substrate of 3A4 and a potent inhibitor of 2D6. If all three drugs were given together, what would the expected levels of each drug to do?

Drug A levels would stay the same, Drug B levels would increase, Drug C levels would increase.

Pharmacist is reading about a new drug that is a non-selective muscarinic antagonist. Which of the following is an expected side effect of this medication?

Dry mouth (anti-muscarinic) When ACh binds to muscarinic receptors, the PSNS is activated causing SLUDD side effects... A muscarinic antagonist causes the opposite effect (anti-SLUDD) such as dry mouth, dry eyes, urinary retention and constipation.

Drug A is a substrate of enzyme X. Drug B is an inducer of enzyme X. A patient has been using Drug A with good results. The patient has now started therapy with Drug B. What will happen to the concentration of Drug A?

Decreased concentration

Stimulation of the alpha-2 adrenergic receptors will cause:

Decreased sympathetic output Centrally acting alpha-2 adrenergic agonists (clonidine) lowers BP and HR by decreasing sympathetic outflow (Epi and NE)

Which of the following drugs can cause hearing damage?

Demadex Lasix Amikacin Tobramycin Loop diuretics (Lasix, Demadex) Aminoglycoside antibiotics (amikacin, tobramycin)

Which of the following are inducers of CYP 3A4?

Dilantin Tegretol St Johns Wort Trileptal Neoral is one of the formulations of cyclosporine

Irenotecan is a chemotherapy drug known to cause many side effects through an increase in acetylcholine. All of the following are expected side effects o increased acetylcholine except:

Increased acetylcholine produces side effect similar to the activation of the parasympathetic nervous system. Rest and Digest SLUDD (salivation, lacrimation, urination, diarrhea/defacation, digestion) DOES NOT INCLUDE PUPIL DILATION

A patient has an estimated creatinine clearance of ml/min. Her potassium level is 4.8. Which of the following drugs will increase her risk of hyperkalemia and should be used with caution.

Enalapril

A 74 yo woman had been taking toprol xl 100 mg daily and warfarin 4 mg daily and amitriptyline 50 mg qhs for several years. Shortly after the death of her spouse, she experienced some depression. She was prescribed citalopram 40 mg daily. What is this patient at risk for due to drug combos?

Increased risk of bleeding and increased risk of arrhythmia SSRIs and SNRIs increase bleeding risk with anticoagulants, even if the INR is in the therapeutic range. Citalopram can increase QT interval (max dose is 20 mg in patients 60+ years). Should also be monitored for serotonin syndrome.

Which of the following drugs contains ketone functional group?

Fenofibrate

Sulfurous drug

Has S in the center with 2 Os attached by double bond If pt has allergy; should also avoid Celecoxib which also contains a sulfonamide group

Know beta-lactam structures

Has lactam ring Square with an N in the square and an S off the square

Phenylephrine is an alpha-1 agonist. Which statement is true about phenylephrine?

It behaves similarly to an endogenous substrate at alpha-1 receptors

MT is using dipyridamole with ASA, per physician recommend. Other Rx meds include demadex, crestor, toprol xl, lotensin, cardizem, klor-con and NTG SL. OTC includes fish oil daily and DHEA. Which statements are correct?

Ibuprofen should not be used in this patient The patient is using two agents that lower HR and it should be monitored (Cardizem and Toprol) The patient would be expected to have a severe drop in BP if he used PDE5 inhibitor

Which of the following statements concerning drug interactions are correct?

If a compound is a p-gp inducer, it can cause the levels of p-gp substrates to decrease if given together. Tacrolimus is a substrate of the p-gp efflux pump Inducers cause more metabolism of drugs that are substrates of the affected enzymes. Important p-gp substrates include digoxin, the calcineurin inhibitors (tacrolimus and cyclosporine), and the anticoagulatns (dabigatran, apixaban, rivaroxaban)

A patient wil A fib has been using warfarin for four months. The INR is stable around 2.3. Select the interaction that can occur with the addition of these other medications:

If aleve is added, the INR would stay the same and the bleeding risk would be elevated. The most common PD interaction is warfarin with NSAIDs, including ASA and ibuprofen (but not selective agents such as celecoxib; however, patietns on warfarin should likely not be using celecoxib due to CVD risk) and with other antiplatelets. These interactions increase bleeding risk, but the INR will not be affected.

A patient with A Fib has been using warfarin for 9 months. The INR is stable between 2.3-2.7. Select the correct interactions that can occur with the addition of other drugs:

If nutritional drinks rich in vitamin K are added, the INR would decrease, bleeding risk would be lowered, but clot risk would be increased If gingko is added, the INR would stay at about the same level, but bleeding risk would be elevated If high doses of fish oils are added, the bleeding risk may become elevated

A patient with a deep vein thrombosis has been using warfarin for four months. The INR is stable around 2.5/ Which of the following interactions is correct?

If rifampin is added, the INR would decrease Rifampin = 2C9 Inducers (which decrease the INR) 2C9 inducers = rifampin, phenobarbital, primidone, phenytoin, St. John's Wort

Drug A is a substrate of enzyme X. Drug B is an inhibitor of enzyme X. A patient has been using Drug A with good results. The patient has now started therapy with Drug B. What will happen to the concentration of Drug A?

Increase Drug A is a substrate of enzyme X. An inhibitor of this enzyme will be added. Inhibitors know out the ability of the enzyme to metabolize the drug, by various mechanisms, such as changing the shape of the enzyme via binding or depletion of a co-factor required for metabolism. Without adequate enzyme, the concentration of substrates will increase as less is broken down by the liver.

Which of the following are side effects of IV epinephrine?

Increased Heart Rate Bronchodilation Increased blood pressure Epinephrine stimulates alpha-1, beta-1, and beta-2 receptors. This creates a SNS or flight or flight response. (NOT pupil constriction)

MR is a patient with severe renal insufficiency and moderate heart failure. She has been using levofloxacin for the past five weeks in an attempt to treat osteomyelitis. Her other medications include methadone, Lotrel, Miralax, and amitriptyline 150 mg QHS for neuropathic pain. Which agents could cause the QT interval to be increase and put the patient at risk for torsades?

Levofloxacin Methadone Amitriptyline The quinolones are QT prolonging agents as are macrolides and some of the other anti-infectives (such as many of the azole antifungals). Lower doses of amitriptyline are typically used for neuropathy.

Drug strucuture with Iodine (specifically 4 Is)

Levothyroxine used to treat hypothyroidism amiodarone has 2 iodine molecules in the structure but 4 with 2 rings is levothyroxine

A major drug interaction can occur with the use of grapefruit juice and which of the following medications?

Lovastatin and nifedipine Lovastatin and nifedipine are both 3A4 substrates. Grapefruit is a potent inhibitor of 3A4

Which of the following is an inhibitor of CYP 3A4?

Pacerone Pacerone is an amiodarone formulation. Apripiprazole and eplerenone are major 3A4 substrates

JW is a 40 year old man with a long standing history of treatment resistant depression. He presents to the ED with a chief complaint of feeling agitated. On PE, he is noted to have tremor, tachycardia, and elevated temperature. Drinks about 6 beers a night. Meds Phenelzine, Vit B12, Sertraline, Bactrim Which of the following could be contributing to his condition?

Phenelzine Sertraline Increase in consumption of tyramine-containing foods/beverages Patient is exhibiting s/s of hypertensive crisis and serotonin syndrome. Patient has been on an MAO inhibitor (phenelzine). Beer is a tyramine containing beverage and is taking an SSRI (sertraline)

Which of the following is an inducer of CYP3A4?

Phenobarbital Inhibitors = erythromycin, amiodarone, clarithromycin, ketoconazole

Theophylline is a substrate of CYP1A2. A patient on long-term theophylline who has been well controlled with infrequent use required of albuterol inhaler, developed a UTI that was difficult to treat. The physician prescribed a 7-day course of Cipro. Which of the following is most likely to occur?

Possible theophylline toxicity Cipor is a moderately strong inhibitor of 1A2 and weaker inhibitor of other isoenzymes

Which of the following statins has the lowest risk of drug interactions?

Pravastatin When the statin level is increased due to statin enzyme inhibition, the risk is higher for muscle toxicity, which would be expressed as muscle aches, soreness or worse, including rapid breakdown of muscle tissue (Rhabdo) The breakdown of muscle tissue causes acute renal failure

Patient taking amiodarone (with 2 iodine structure)

Puts patient at risk for: Hyperthyroidism Hypothyroidism Iodine allergy reaction

Oxycodone cannot be used safely with CYP3A4 inhibitors. What could happen if a pharmacist missed the interaction.

Respiratory Depression Sedation Oxycodone, if overdosed, can cause respiratory depression. The 3A4 inhibitors block the metabolism of oxycodone. This includes oxycodone by itself and the oxycodone-APAP combo.

JD is a 77 year old female who fell and broke her ankle. It has not healed well and she is using an assistive device to walk. She is very scared about having another fall. She does not have any children to help her and worries that if she has a hip fracture it will put her into a nursing home. Which of the following agents increase the risk of the patient having a fall that could result in fracture?

Restoril Remeron Flexeril CNS side effects are caused by drugs that enter the CNS and primarily involve drugs that cause sedation, dizziness, confusion, and altered consciousness

A patient with A fib has been using warfarin for nine months. The INR is stable around 2.3. The patient is having a return of major depressive disorder, which she had had in the past and treated (unsuccessfully) with OTC st johns wort. She has asked for a prescription agent that will not interact with her other daily medications. Which of the following agents would not increase bleeding risk in this patient and could be used for a suitable trial?

SSRI and SNRIs increase bleeding risk. They are sometimes used together, but there is an increasing awareness that this is dangerous. The INR does not increase, but the bleeding risk increases. Bupropion is an appropriate agent to trial. It is primarily dopaminergic.

Which of the following statements describes the expected action of a drug that is a selective beta 2 agonist

Stimulation of beta-2 adrenergic receptors Relaxation of bronchial smooth muscle Selective beta 2 agonist (albuterol) is expected to stimulate beta-2 receptors (lung, bronchial smooth muscle) leading to bronchodilation. It does mimic the effects of natural catecholamines predominantly in the lungs and bronchial smooth muscle. Another beta 2 agonist is terbutaline; can be used as a bronchodilator, but also to reduce the uterine contractions in preterm labor (relax uterine smooth muscle)

Amitriptyline Structure

TCA - has three rings in structure

VN uses imitrex for migraines 2-4 times each month. Recently she began to use sarafem 10 mg daily for premenstrual dysphoric disorder. In addition, she uses ultram once or twice daily for HA relief. She is at risk for the following symptoms:

Tachycardia, Sweating Diarrhea Agitation Muscle twitching or rigidity Combining serotonergic agents increases risk for serotonin syndrome. (specifically ultram)

Which of the following statements concerning drug interactions are correct?

The P-gp efflux pump moves drug from inside the body to outside by pumping the drug into the gut where it can be eliminated Many of the same inhibitors of CYP450 enzymes also inhibit p-gp efflux pump Induction has a lag effect which means that the full effect of adding an inducer is not seen right away, and it takes time for the induction to dissipate once the inducer has been discontinued. A prodrug is a compound that is inactive until it is converted into an active form.

Cyclosporine is an inhibitor of the P-glycoprotein efflux transporter. If a drug is a substrate of p-gp, what will happen to the drug concentration if it is given to a patient receiving cyclosporine?

The concentration of the substrate drug will increase. P-gp are efflux transporters found in the gut and other organs. They pump drugs back into the gut (out of the bloodstream). If a drug is subject to efflux, the substrate drug concentration will increase.

A patient with asthma, COPD, and seizures has been using theophylline and valproate for many years. Recently, the neurologist took the patient off valproate and started phenytoin due to an increase in seizure activity. The patietn has been under a lot of stress and took up smoking again. She smokes about or cigs daily. Which statements are correct?

The smoking will decrease the theophylline level and the patient may have impaired asthma control. The phenytoin will decrease the theophylline level and the patient may have impaired asthma control. Many inhibitors increase the theophylline level and many inducers decrease the theophylline level. Do not over ride theophylline drug interactions without checking because this drug has a narrow therapeutic index- this means that it does not take much to drive the level down below efficacy, or up into the toxic range. Smoking causes induction and can lower the efficacy of some substrates including theophylline and clozapine

BH is using estrogen and progestin birth control pills for contraception. She recently received a prescription for phenytoin. Select the best description for the interaction between these medications:

The phenytoin is an inducer of the metabolism of the estrogen in the birth control pill; it will reduce the effectiveness of the contraception Phenytoin is a potent inducer. Substrates are drugs that are metabolized by the CYP enzymes. Inducers result in higher levels of enzymes, which decrease levels of the substrate drugs. Inhibitors inactivate enzymes (causing less drug metabolism), and increase levels of the substrate drugs.

MAO inhibitor is being taken. Which of the following drugs can be dispensed and will not cause concern with the concurrent use of his antidepressant?

Toprol XL Alprazolam A patient using a MAOI cannot take phenyephrine, buspirone, levodopa, linezolid, lithium, meperidine, SSRI/SNRI, TCAs, tramadol, mirtazapine, dextromethorphan, cyclobenzaprine, levodopa, a few triptans, St Johns Wort and serotonergic drugs due to the risk of accumulation and serotonin syndrome.

Which of the following are inhibitors of CYP 3A4?

VFEND (voriconazole) Biaxin Cardizem Grapefruit

Select the correct statements concerning the drug interaction between valproic acid and lamotrigine?

Valproic acid inhibits lamotrigine metabolism When using these two medications at the same time, the appropriate lamictal starter kit should be used This interaction increases the risk for a severe lamotrigine induced rash

Which of the following drugs can cause hearing damage?

Vancomycin Edecrin Gentamicin Doans extra strength Doans is an OTC salicylate.

Amiodarone is both a substrate and inhibitor of CYP 2C9, 2D6, 3A4. The pharmacist is aware that these medications must have their doses reduced when dispensing amiodarone....

Warfarin Digoxin Although digoxin is largely renally excreted, a percentage of the drug is metabolized hepatically. All these agents must have the doses decreased by 30-50% when beginning amiodarone.

Which of the following statements best describes warfarin metabolism?

Warfarin is racemic; the S-isomer is more potent and is primarily a substrate of CYP2C9

GV has been using a MAO inhibitor to help control her depression for many years. She is careful to check that other drugs and foods do not interact with her medicine. Which of the following drugs can be dispensed to GV and will not cause concern with the concurrent use of her antidepressant?

Xalatan Boniva Prempro MAO inhibitors should not be given with stimulants or with adrenergic agents such as pseudoephedrine (component of claritin D) due to risk of hypertensive crisis

A patient is at risk for A fib; she has had this a fib in the past. The medical team has asked the pharmacist to check for drugs on her profile which can increase her risk of arrhythmia. The pharmacist should include the following medication:

Ziprasidone Ziprasidone can cause additive QT prolongation and must be used with caution in patients with any arrhythmia risk.

Gentamicin structure

aminoglycoside antibiotic 3 separate rings 2 with an O within the ring