Pharmacology Flashcards
1
Q
What are diuretics role
A
- inhibit the reabsorption of sodium
- increase urine flow
2
Q
Thiazide diuretics can be used for what?
A
- hypertension
3
Q
Define oedema
A
- imbalance between the formation and absorption of interstitial fluid
4
Q
Name some conditions which cause oedema?
A
- nephrotic syndrome
- congestive heart failure
- hepatic cirrhosis with ascites
5
Q
Nephrotic syndrome is a disorder of?
A
- glomerular filtration
6
Q
Proteins in the urine causes what to the oncotic pressure of plasma?
A
- decreases
7
Q
Blood volume decrease due to proteinuria activates what system?
A
- RAAS
8
Q
How does congestive heart failure arise
A
- from reduced cardiac output and renal hypoperfusion
9
Q
How does hepatic cirrhosis cause ascites
A
- increased pressure in hepatic portal vein
- decreased albumin
- loss of fluid into peritoneal cavity
- activation of RAAS
10
Q
Main sites of reabsorption of sodium
A
- proximal convoluted tubule
- thick ascending limb of loop of henle
- early distal convoluted tubule
- collecting tubule
11
Q
What do carbonic anhydrase inhibitors block?
A
- Na+/H+ exchange
12
Q
What do loop diuretics block?
A
- triple transporter
- Na+/K+/Cl-
13
Q
What do thiazide diuretics block
A
- Na+/Cl-
14
Q
What do potassium sparing diuretics block?
A
- Na+/K+ exchange
15
Q
Diuretics must enter the ____ to work
A
- filtrate
16
Q
How do diuretics enter the filtrate
A
- glomerular filtration
- OATs (acidic drugs)
- OCTs (basic drugs)
17
Q
What transports acidic diuretic drugs
A
- organic anion transporters
18
Q
What transports basic diuretic drugs
A
- organic cation transporters
19
Q
Drug interactions of OATs
A
- diuretics
- simvastain
- penicillin
- nsaids
20
Q
Drug interactions of OCTs
A
- diuretics
- atropine
- metformin
- morphine
21
Q
Overall affect of loop diuretics
A
- decrease tonicity of medullary interstium
- prevent dilution of filtrate
- increase Na+ load in distal nephron
- increase Ca2+and Mg2+ excretion
22
Q
Medical side effects of loop diuretics
A
- hypocalcaemia
- hypomagnesia
- hyperuricaemia
- loss of hearing
23
Q
Main loop diuretics used
A
- furosemide
- bumetanide
24
Q
Where are loop diuretics absorbed?
A
- absorbed from the GI tract
- bind to plasma proteins
- enter by OAT
25
Indications for loop diuretics
- pulmonary oedema
- chronic heart failure
- nephrotic syndrome
- increased urine volume in acute kidney failure
- to reduce hypercalcaemia
26
Contraindications of loop diuretics?
- severe hypovolaemia or dehydration
| - avoid in gout
27
Name a thiazide diuretic
- bendrolumethiazide
28
Explain how thiazide diuretics work
- act at early distal convoluted tubule
- block Na+/cl- co transporter
- absorbed by OAT transporters
- promote reabsorption of Cli-
29
Name a thiazide diuretic like drug
- chlortalidone
| - indapamide
30
What are some uses for thiazide diuretics
- mild heart failure
- hypertension
- severe resistant oedema
- renal stone disease
- nephrogenic diabetes insipidus
31
Why might thiazide diuretics be used in renal stones
- promote reabsorption of cl-
| - reduce cl- in urine
32
Contraindications of thiazide diuretics
- hypokalaemia
33
Adverse effects of thiazide diuretics
- hypokalaemia
- metabolic acidosis
- hypomagnesaemia
- erectile dysfunction
34
Explain hypokalaemia as a result of diuretics
- increased Na+ load
- charge seperation
- increased driving force on K+
- K+ secretion
- K+ washed away
35
Name 2 different types of potassium sparing diuretics?
- spironolactone / eplerenone
| - amilodride
36
Explain how spironolactone works
- competes against aldosterone
- increases Sodium excretion
- decreases K+ excretion
37
Explain how amilodride works
- blocks Na+ channel
- increases Na+ excretion
- increases k+ reabsorption
38
How does amiloride enter the kidney
- octs
39
when should the use of potassium sparing diuretics be avoided
- severe renal impairment
- hyperkalaemia
- Addisons
40
Usage of potassium sparing diuretics?
- heart failure
- Conns
- resistant hypertension
41
What are given in conjunction with potassium sparing diuretics?
- thiazide or loop diuretics
| - potassium sparing have a modest diuresis
42
Which diuretic enter the cells via a oct?
- Amiloride hydrochloride
| - Na+ blocker
43
What diuretics can cause hyperkalaemia?
- potassium sparing diuretics
44
What diuretics can cause hypokalaemia?
- thiazide and loop diuretics
45
Name an osmotic diuretic
- Mannitol
| - given iv
46
Affect of osmotic diuretics
- suppress movement of water
| - reduce reabsorption of sodium
47
How do osmotic diuretic enter the cell?
- glomerular filtration
- increases osmolarity of filtrate
- reduces reabsorption of sodium
48
When are osmotic diuretics used?
- prevention of acute hypovolaemic renal failure
| - treatment of raised intracranial pressure
49
Adverse effects of osmotic diuretics?
- transient expansion of blood volume
| - hyponatraemia
50
Name a carbonic anhydrase inhibitors?
- acetazolamide
51
What traditional diuretic is no longer used as a diuretic?
- carbonic anhydrase inhibitors
52
How do carbonic anhydrase inhibitors work?
- increased excretion of HC03, Na+, k+ and H2O
53
Carbonic anhydrase inhibitors can be used for?
- glaucoma
- prophylaxis for altitude sickness
- infantile epilepsy
54
Carbonic anhydrase inhibitors cause a what pH?
- Metabolic acidosis
| - excretion of bicarbonate
55
Affect of carbonic anhydrase inhibitors on the urine?
- alkalinising
| - can be used for renal stones
56
Affect of aldosterone
- secretion from zona glomerulosa
- increased activity of sodium channels
- enhanced tubular Na+ reabsorption
57
How does Vasopressin work
- increased aquaporin 4
| - enhanced H2O reabsoprtion
58
Treatment of diabetes insipidus
- desmopressin (synthetic analogue of vasopressin)
59
What drugs may cause secondary vasopressin inhibition?
- lithium
- demeclocycline
- vaptans
60
What do vaptans block?
- block V1 and V2
| - blocks ADH effect
61
Uses of vaptans
- SIADH
| - polycystic kidney disease
