Drugs that act on the Kidneys

Question 0

Within the nephron, what order do you find the following:

Distal Tubule, Collecting Duct, Proximal Tubule, Loop of Henle, Glomerulus

Answer 0

Glomerulus - Proximal Tubule - Loop of Henle - Distal Tubule - Collecting Duct

Question 1

What organ’s job is to balance salts and fluid within the body?

Answer 1

The Kidney

Question 2

What type of drug increases the amount of fluid and salts excreted by the kidney?

Answer 2

Diuretics

Question 3

What drug is used to sort out oedema, hypertension and glaucoma?

Answer 3

Diuretics

Question 4

Diuretics increase urine production. How does this help get rid of oedema?

Answer 4

It draws away more fluid from the swollen areas in the tissue.

This reduces swelling and the area returns to normal.

Question 5

Diuretics increase the volume of urine produced.

What 3 things do they decrease in order to treat hypertension?

Answer 5

Blood Volume
Pressure on blood vessels
Blood Pressure

Question 6

What are the 3 ways salts and water move around between cells etc in the body?

Answer 6

Active Transport = Pumps
Passive Transport = Channels
Osmosis

Question 7

Pumps move salts using energy.

Name the 3 pumps that do this:

Answer 7

Sodium/Potassium Pump
Sodium/Chloride Pump
Sodium/Potassium/Chloride Pump

Question 8

What is the name for openings in the cell membrane, that are ion selective and allow salts to move through (no energy required)?

Answer 8

Channels

Question 9

What does ion selective mean?

Answer 9

This is where only certain ions are allowed through, whether this may be sodium, potassium or chloride

Question 10

What is osmotic effect?

Answer 10

Water follows salt

Question 11

What are the 3 main classes of diuretic?

Answer 11

Thiazide and related
Loop
Potassium Sparing

These work on slightly different parts of the nephron

Question 12

Which diuretic acts on the distal convoluted tubule?

Answer 12

Thiazide and Related Diuretics

D in thiazide = distal

Question 13

Which class of diuretic is used to treat oedema within MILD heart failure, liver and kidney disease or steroid/hormone treatment, and for LONG TERM hypertension?

Answer 13

Thiazide Diuretics

Question 14

What are bendroflumethazide, metolazone and indapamide examples of?

Answer 14

Thiazide Diuretics

Question 15

Which 2 types of diuretic are metabolised by the liver and excreted only in the urine?

Answer 15

Thiazide and Loop diuretics

Question 16

Which class of diuretic blocks the chloride pump, increases the excretion of sodium chloride and then increases the excretion of potassium?

Answer 16

Thiazide

Question 17

What is the mechanism of action for thiazide diuretics?

Answer 17

Blocks the chloride pump, increases the excretion of sodium chloride and then increases the excretion of potassium.

IDE = Thiazide

Question 18

When thiazide diuretics block the chloride pump, why does this also increase the excretion of sodium and potassium?

Answer 18

Chloride is negatively charged and sodium and potassium are positively charged.
As the chloride is being excreted the cells want to balance out.

Question 19

When should thiazide diuretics be taken? Why (think of how long it takes for them to act)?

Answer 19

In the morning. They act within 1-2hours (rapidly), so this stops the patient being up all night.

Question 20

What are the side effects of thiazide diuretics?

4 Hs and 2 cautions

Answer 20

Hypokalaemia, Hypocalcemia, Hyperuricemia, Hyperglycemia
(low potassium, low calcium, high uric acid and high sugar)

Caution with patients w/ arrhythmias, diabetes, on lithium, NSAIDS or pregnant/breastfeeding

Question 21

Where do loop diuretics act?

Answer 21

The ASCENDING loop of Henle

Question 22

Which diuretic is used for oedema resulting from SEVERE heart failure or acute ventricular failure (pulmonary oedema), and hypertension?

Answer 22

Loop Diuretics - loop = Loop of Henle

Potent = severe stuff = loopy?

Question 23

What are furosemide and bumetanide examples of?

Answer 23

Loop diuretics

FUROSEMIDE AND BUMETANIDE

Question 24

What is the mechanism of action for loop diuretics?

Answer 24

They block the sodium/potassium/chloride pump increasing the excretion of all 3. Makes sense - severe and loopy = big pump More urine and hardly any ions reabsorbed

Question 25

When should powerful loop diuretics be administered? Why?

Answer 25

Morning and before 4pm. Twice daily - act very fast but not for as long. Don't want to be up all night

Question 26

Which diuretic has side effects of hypokalaemia, hyponatraemia, hypervolemia and deafness? (also caution should be taken for patients with Arrhythmias, diabetes, taking lithium and pregnant

Answer 26

Loop Diuretics Deafness = 8th cranial nerve damage from I.M or I.V admin

Question 27

What is the site of action for potassium sparing diuretics?

Answer 27

The distal tubule and collecting duct | things on the end - late Sparing - being nice comes last

Question 28

Which diuretic is used for oedema resulting from heart failure and liver disease, hypertension and hypokalemia alongside other diuretic types?

Answer 28

Potassium Sparing

Question 29

Which specific diuretic is used for primary hyperaldosteronism (Conn's Syndrome)?

Answer 29

Spirolactone

Question 30

Spirolactone, amiloride (a sodium channel blocker) and eplerenone (an aldosterone antagonist) are examples of what?

Answer 30

Potassium Sparing Diuretics

Question 31

Which diuretic is metabolised by the liver and excreted in both urine and bile?

Answer 31

Potassium Sparing

Question 32

What is the general mechanism of action for potassium sparing diuretics? How does spironolactone do this?

Answer 32

It increases sodium and water excretion along with chloride and calcium, however it decreases the excretion of potassium and hydrogen. Spironolactone blocks the aldosterone receptor. It blocks sodium being reabsorbed thus increasing urine/water - and lessens the sodium potassium pump so that potassium is not pumped out

Question 33

Which class of diuretic is fairly week?

Answer 33

Potassium Sparing Diuretics

Question 34

Which diuretic has possible side effects of hyperkalaemia (requiring a low potassium diet) and the requirement for close monitoring of electrolyte levels - especially for people also taking ACE inhibitors, angiotensin receptor antagonists and B antagonists?

Answer 34

Potassium Sparing Diuretics

Question 35

What diuretic is a patient likely to be taking if we need to monitor their electrolyte levels? (Particularly if taking ACE inhibitors, SARTANS, B antagonists)?

Answer 35

Potassium Sparing Diuretics

Question 36

What is the site of action for anti-diuretics?

Answer 36

The Collecting Tubule Right at the end - anti

Question 37

What are anti-diuretics used for?

Answer 37

To treat Central Diabetes Insipidus (the lack of ADH/anti-diuretic hormone)

Question 38

What type drug is used to treat Central Diabetes Insipidus? What is this?

Answer 38

Anti-diuretics - a lack of anti-diuretic hormone

Question 39

What are vasopressin and desmopressin examples of?

Answer 39

Anti-diuretics Pressin = pressin for a wee

Question 40

What is the mechanism of action of anti-diuretics?

Answer 40

They increase the number of water channels by V2 receptors, which increases passive reabsorption of water

Question 41

Anti-diuretics increase water channels, thus increasing the passive reabsorption of water. What receptors do they act on?

Answer 41

V2

Question 42

Which anti-diuretic has a short duration of action, is administered by injection/infusion and also increases blood pressure due to binding to V1 receptors?

Answer 42

Vasopressin

Question 43

Which anti-diuretic has a longer duration of action, is administered as a nasal spray or tablets and is V2 selective so does not affect blood pressure?

Answer 43

Desmopressin

Question 44

What do you need to ensure is balanced when dosing anti-diuretics?

Answer 44

Want to make sure there is enough urine production to prevent water intoxication