Polypharmacy

Question 1

What relevance does medication have to physio?

Answer 1

• Causing symptoms (dizziness, swollen ankles)
• Controlling symptoms to enable treatment (pain,
  SOB)
• Sedating (ability to comply with instructions)
• Indicating underlying disease process (arthritis)
• Affect observations (pulse, BP)

Question 2

How can drugs within the same class be different?

Answer 2

Difference properties

Question 3

What is the difference between brand and generic drugs?

Answer 3

• Active drug = generic name (e.g. ibuprofen)

- Company name = brand name (e.g. nurofen)

Question 4

What is the passage of drugs through the body (pharmokinetics)?

Answer 4

• Administration: Swallow, inject, topical
• Absorption: Fraction absorbed (e.g. injection = 100% absorbed, swallowed = less absorbed)
• Distribution
• Metabolism: Liver & other sites
• Excretion

Question 5

How do drugs work?

Answer 5

• Interact with proteins to produce an effect

- Agonist, antagonist or partial agonist

Question 6

What are the 4 main types of proteins that interact with drugs?

Answer 6

• Receptors
• Ion channels
• Enzymes
• Transporters (carriers)

Question 7

What is the difference between an agonist, antagonist & partial agonist?

Answer 7

• Agonist: drug that elicits a response upon binding to a receptor
• Antagonist: drug binds to a receptor without causing activation, but prevents the agonist from binding
• Partial agonist: drug binds to a receptor causing a submaximal response (compared to agonist)

Question 8

What is polypharmacy?

Answer 8

When a patient is on

• 5+ different medications OR
• 12+ doses per day
• Hypopolypharmacy: 10+ medications

Question 9

What are the adverse outcomes of polypharmacy?

Answer 9

• 4.5+ medications = increased mortality, falls, disability, frailty
• Increased drug interactions (1-way & complex)

Question 10

What are the types of drug interactions?

Answer 10

• Pharmocokinetic: Altered concentration

- Pharmacodynamic: Altered effect

Question 11

What are the types of pharmacokinetic interactions?

Answer 11

• Bioavailability: Absorption or first-pass metabolism
• Clearance: Metabolism or excretion of active drug
• Distribution: Cell membrane transport to site of action

Question 12

What is the mechanism & mode of pharmacodynamic interactions?

Answer 12

• Mechanism: Molecular signal (e.g. receptor)

- Mode: Physiological effect

Question 13

How can drug-drug interactions alter metabolism of drugs?

Answer 13

• One drug may inhibit the enzyme that metabolises another

- E.g. erythromycin inhibits the enzymes that metabolise warfarin&raquo_space; warfarin concentration increases

Question 14

What age-related changes are relevant to pharmacy?

Answer 14

• Pharmacokinetic changes: Impaired renal function
• Pharmacodynamic changes: Changes in receptors & target organ response (increased sensitivity to drugs)
• More conditions
• More medications

Question 15

What drugs are most relevant to physio?

Answer 15

• Analgesics
• Bloods (anticoagulants)
• Cardiovascular
• Endocrine (diabetes)
• Genitourinary (anticholinergics)
• Neurological (PD, muscle relaxants)
• Respiratory
• Rheumatological (RA, OP)
• Psychotropics (antidepressants)

Question 16

What is a triple whammy?

Answer 16

• Occurs when pt takes a combination of NSAIDs, diuretics & ACEIs or ARBs
• Each work on different areas of the kidney, so when combined can cause kidney failure

Question 17

What is the function of each of the drugs involved in the triple whammy?

Answer 17

• NSAIDs: Block prostaglandin production, reduced blood flow to glomerulus
• Diuretics: Reduced blood flow to glomerulus
• ACEIs or ARBs: Reduced glomerular filtration rate via efferent arteriole dilation

Question 18

What are the classes of CV drugs?

Answer 18

• Beta blockers
• Alpha receptor antagonists
• Calcium channel blockers
• ACE inhibitors
• Angiotensin 2 receptor antagonists (A2RA)
• Nitrates
• Diuretics
• Cardiac glycosides
• Vasodilators

Question 19

What is the function of beta blockers (“-lol”)?

Answer 19

• Block sympathetic stimulation of the heart (reduce HR)
• Reduce SBP, HR, contractility & CO (decrease myocardial O2 demand, increase exercise tolerance)
• Increase threshold for ventricular fibrillation

Question 20

What is the major side effect of ACEI & A2RA?

Answer 20

• Cough (most likely) or angiodema
• 5-15% population, females 3x more likely

ACEI = "-pril"
A2RA = "-sartan"

Question 21

What is the function & side effects of nitrates?

Answer 21

• Function: Vasodilators, open blood vessels to increase perfusion to the heart
• Side effects: Headaches, sudden BP drop

Question 22

What are two examples of antiplatelets?

Answer 22

• Aspirin

- Clopidogrel

Question 23

What is the function of aspirin?

Answer 23

• Inhibits cyclo-oxygenase
• Irreversible
• All angina/STEMI/non-STEMI patients
• Not with NSAIDs (decreases effect)

Question 24

What is the function of clopidogrel?

Answer 24

• Blocks platelet aggregation
• Intolerance/stents/events on aspirin
• Can be combined

Question 25

What is the function of statins?

Answer 25

• HMG-CoA reductase inhibitors
• Stabilise lipid rich plaques
• Prevent rupture
• Improve lipid profile by reducing cholesterol synthesis
• ?antiplatelet action

Question 26

What has research found regarding statin & muscles?

Answer 26

• Muscle aches, fatigue, myopathy, rhabdomyolysis no more common in the statin arm than in the placebo arm
• But more common at higher doses than lower doses
• Every 100,000 patient years there will be 190 cases of mild muscle pain, 5 cases of myopathy, 1.6 cases of rhabdomyolysis

Question 27

What are the different types of diuretics?

Answer 27

• Loop diuretics (e.g. frusemide)
• Thiazide
• Thiazide-like
• Potassium sparing
• Aldosterone antagonists