Drugs for Hypo/Hyperkalemia

Question 1

What defines Hyperkalemia?

Answer 1

Plasma [K+] > 5.2

Question 2

What defines Hypokalemia?

Answer 2

Plasma [K+] < 3.7

Question 3

Is K+ usually inside or outside of the cell?

Answer 3

Inside

Question 4

If K+ is outside of the cell, then it will be?

Answer 4

Hyperkalemia

Question 5

What things cause K+ to go inside the cell, thus causing more hypokalemic actions?

Answer 5

Insulin
Beta2 Agonists
Alpha Antagonists
Aldosterone deficiency

Question 6

What classes of drugs are K+ sparing diuretics?

Answer 6

Aldosterone Antagonists

Na+ channel blockers

Question 7

Where do K+ sparing diuretics act?

Answer 7

Cortical Collecting Duct

Question 8

What classes of drugs are K+ losing diuretics?

Answer 8

Loops
Thiazides
Carbonic Anhydrase (-)’s
Osmotic diuretics

Question 9

MOA for Thiazides and where do they act?

Answer 9

Block Na+ Cl- channels

– act at distal convoluted tubule

Question 10

MOA for Loops and where do they act?

Answer 10

Block Na+ K+ 2Cl- channels

– act at thick ascending limb

Question 11

Carbonic Anhydrase (-)’s and Osmotic Diuretics are used less often, but where do they act?

Answer 11

Proximal tubule and thin descending limb

Question 12

What are 2 reasons to give Diuretics?

Answer 12

HTN

Edema due to heart/kidney/liver failure

Question 13

What are the 4 loops?

Answer 13

Furosemide
Torsemide
Bumetanide
Ethacrynic Acid

Question 14

Loops work in patients with _____ unlike Thiazides

Answer 14

Low GFR

Question 15

Loops and Thiazides should not be used in patients with an allergy to?

Answer 15

Sulfa

Question 16

Which Loop can be used in patients with a sulfa allergy?

Answer 16

Ethacrynic Acid

Question 17

What is a possible side effect of Furosemide?

Answer 17

Ototoxicity

Question 18

Which loop has a longer half life, better oral absorption and works better in HF?

Answer 18

Torsemide

Question 19

Which loop has more predictable oral absorption?

Answer 19

Bumetanide

Question 20

What are the 4 Thiazides?

Answer 20

HCTZ
Chlorothiazide
Chlorthalidone
Metolazone

Question 21

Which Thiazide has poor oral absorption?

Answer 21

Chlorothiazide

Question 22

Which Thiazide has a half life of 40-60 hours and is preferred by some HTN specialists?

Answer 22

Chlorthalidone

Question 23

Which Thiazide is preferred with CHF?

Answer 23

Metolazone

Question 24

Why do Thiazides cause Hypercalcemia?

Answer 24

More reabsorption in proximal tubule due to volume contraction

Question 25

Between loops and thiazides, which cause more Magnesium loss?

Answer 25

Thiazides

Question 26

What are the Na+ channel blockers?

Answer 26

Triamterene | Amiloride

Question 27

What are the Aldosterone Antagonists?

Answer 27

Spironolactone | Eplerenone

Question 28

What is a possible side effect of the K+ sparing diuretics?

Answer 28

(Na+ channel blockers and Aldosterone antagonists) | = Hyperkalemia

Question 29

Spironolactone is also a ____ which can cause?

Answer 29

Partial agonist at androgen receptors | => Amenorrhea, Hirsutism, Gynecomastia

Question 30

What can Spironolactone decrease with post-MI heart failure?

Answer 30

Decreases Fibrosis on the heart

Question 31

Which Aldosterone Antagonist is more selective?

Answer 31

Eplerenone

Question 32

What are the symptoms of Hypokalemia?

Answer 32

Lethargic, Lots of urine output, arrhythmias, cramps, low BP

Question 33

What is the treatment for Hypokalemia?

Answer 33

K+ replacement

Question 34

IV K+ replacement is used with severe Hypokalemia. What kind is used and how fast?

Answer 34

K+ chloride/acetate -- 10-20 mEq/hr

Question 35

Oral K+ replacement should be taken with water to prevent?

Answer 35

GI irritation

Question 36

What are the symptoms of Hyperkalemia?

Answer 36

Bradycardia, low urine output, numb, weak, paralysis

Question 37

What are the ECG changes with Hyperkalemia?

Answer 37

Peaked T wave and Widened QRS

Question 38

What are the 3 steps to treating Hyperkalemia?

Answer 38

1. Antagonist cardiac effects 2. Redistribute K+ into cells 3. Facilitate K+ loss

Question 39

With Hyperkalemia, how do you antagonist cardiac effects?

Answer 39

Give IV calcium

Question 40

With Hyperkalemia, how do you redistribute K+ into the cells?

Answer 40

Give Insulin, Glucose or Beta2 agonists

Question 41

With Hyperkalemia, how do you facilitate K+ loss?

Answer 41

Give K+ losing diuretics, mineralcorticoids or dialysis

Question 42

If there is Acidosis, what is the level of K+ usually?

Answer 42

Hyperkalemia