Diuretics Flashcards
What are one of the early signs of diabetes?
- Polyurea
- Too much urination
What do diuretics do?
Control the direction of sodium
Why is controlling sodium important?
- Because where sodium goes, water follows
- Useful for controlling urine output
- Drugs block sodium
Describe diabetes mellitus
- Elevates glucose
- Glucose can be used to move water- diuretic
- Elevated sugar = polyurea
- Acts as an osmotic
- High plasma glucose blocks glucose reabsorption
Describe diabetes insipidus
- Sodium issue
- Plasma hypernatremia reduced by diuretic on Na+ reabsorption
- With a sodium problem, diuretics can be used
What are the functions of kidney?
- Water volume- ADH
- Acid/balance- carbonic anhydrase
- Regulates BP- RAS
- Filtration, reabsorption and excretion
- Oxygen sensing- part of regulating BP
What is the main purpose of diuretics?
- Helps rid body of sodium and water
- Reduces oedema
What are the uses of diuretics?
- Diabetes insipidus
- Kidney disorders (Stones)
- Oedema
- Polycystic ovary syndrome
- Osteoporosis- regulates Ca
- Female hirsutism
- High BP
- Congestive heart failure
- Cirrhosis (ascites)
What are some non-pharmacologic treatments?
- Lifestyle changes
- NSAID restriction
- Salt restriction
- Caffeine
- Diet/exercise/alcohol/smokng
How can NSAID restriction be helpful?
- Cyclooxygenase blocks production of prostaglandins
- E.g. inhibiting prostaglandins blood flow to kidney is reduced
- Stimulates compensatory
How is salt restriction important?
- Plasma sodium is important for the regulation of water
How is caffeine important?
- Causes increase in strength of heartbeat- increases perfusion to kidney
Why are diet/exercise/alcohol and smoking important?
- Central obesity
- Drinking alcohol over time
- Stop responding to increase in fluid- retains
What are the different types of diuretics?
- Loop
- Thiazide
- Potassium sparing
- Carbonic anhydrase
- Osmotic
- Xanthines
- Glucose
Give examples of loop diuretics
- Furosemide
- Bumetanide
When might loop diuretics be used?
- Peripheral and pulmonary oedema
- Congestive heart failure
- Effective in diminished renal function
How do loop diuretics work?
- Inhibit Na/Cl/K reabsorption in the thick ascending loop on Henle
- High capacity so potent
What are the adverse effects of loop diuretics?
- Can cause osteoporosis- due to Ca loss
- Electrolyte imbalance (might cause deafness)
Hypokalaemia- blocks reuptake
Give examples of thiazide diuretics
- Bendroflumethiazide, metolazone, chlortalidone
- Similar to carbonic anhydrase- developed from them
What are the uses of thiazide diuretics?
- Mild heart failure
- Hypertension- shown to reduce stroke
- Oedema
- Ascites in cirrhosis
- Retention of calcium- may help in osteoporosis
How do thiazide diuretics diuretics work?
- Only blocks sodium and chloride
- Excess sodium in the lumen
- Water goes into the lumen
- Water loss this way
- Not as potent as loop, don\t affect potassium
- Excretion of Na/Cl and water increased
What are the adverse effects of thiazide diuretics?
- Weakness, impotence, postural hypotension about regulating dose
- Hypokalaemia- arrhythmias, supplement with potassium
- Hyperuricaemia, nitrogenous waste, secretion of thiazides competes with uric acid secretion- can precipitate gout
