Diuretics Flashcards
What channels do loop diuretics block
NKCC2 channels in the loop of henle
Give an example of a loop diuretic
Fruesmide
What affect on calcium do loop diuretics have
Cause hypocalcaemia
What are the ADRs for loop diuretics
Ototoxcity, alkalosis, gout, increased LDL
What affect on potassium do loop diuretics have
Hypokalaemia as the salt and water not absorbed here is moved to the collecting duct which is absorbed by ENaC which is linked to a ROMK channel so more K is lost
What channels do thiazides block
NCCT channels in the DCT
What are thiazides used to treat
Hypertension as they are also vasodilators
What are the ADRs for thiazides
Gout, hyperglycaemia, increased LDL
What do thiazides do to calcium leaves
Gives hypercalcaemia
What do thiazides do for potassium levels
Hypokalaemia
What channels do amiloride block
ENaC in collecting duct
When do you use amiloride
When a patient with hypokalaemia needs a diuretic
What does amiloride do to potassium levels
Hyperkalaemia
How does spironolactone work
Aldosterone antagonist
What does aldosterone do
Inserts more ENaC into the collecting duct - therefore, more salt and water reabsorbed
Speeds up the Na/K/ATPase so more potassium is pumped out of the cells into the blood
When is spironolactone used
Heart failure, hypertension and hyperaldosteronism
What does spironolactone do to the potassium levels
Hyperkalemia
Give an example of an ADH antagonist
Lithium
What do ADH antagonists do
Inhibits the actions of ADH so you lose water only
True or false; ADH antagonists give diuresis and naturesis
False - only diuresis
When do you use ADH antagonists
When the patient is hyponatreamic
When are carbonic anhydrase diuretics used
Glaucoma
What happens to the acid base balance when using carbonic anhydrase
Lose bicarb giving acidosis
What are osmotic agents used for
Swelling in the brain
What are some general adverse drug reactions of diuretics
Anaphylaxis, hypovoleamia, hypotension, electrolyte disturbance, metabolic Abnormalities
What are the major cause of hyperkalaemia
Reduced urine production
Increased tissue damage
What are the effects of hyperkalaemia
Cardiac arrhythmias
How do you treat cardiac arrhythmias due to hyperkalameia
- Calcium gluconate - protect the heart
- Dextrose/insulin - lowers serum K
- Calcium resonium - removes K
How doe NSAIDs harm the kidneys
Inhibit the production of prostaglandins which cause vasodilation on the afferent arteriole - therefore, if this cant dilate then the GFR will drop further
How do ACE inhibitors affect the kidneys
Inhibit vasoconstriction of efferent arteriole so allows a further drop in GFR
Give some reasons for diuretic resistance
- swelling in the gut - cant absorb drugs
- heart failure - cant pump enough blood to kidneys
- Liver problems - drugs cant be transported with albumin
- Kidney problems
- Salt - lose the effect of the diuretic as the water will follow the salt
How does alcohol work as a diuretic
Inhibits ADH release
How does caffeine work as a diuretic
Increases GFR and reduces Na reabsorption
Which diuretics work in the PCT
Carbonic anhydrase inhibitors
Osmotic diuretics
Which diuretics work in the loop of henle
Loop diuretics
Which diuretics work in the DCT
Thiazides
Which diuretics work in the CD
Spironolactone
Amiloride
ADH antagonists
What diuretics are used for liver disease
Spironolactone
Loop diuretics
What diuretics are used for nephrotic syndrome
Loop diuretics in high doses
What diuretics are used for oedema
Loop diuretics
What diuretics are used in hypertension
- Thiazide
Possibly spironolactone also
What diuretics are used for heart failure
Loop diuretics
