Diuretics

1. Presented By: Ms. Kalaivani Sathish M. Pharm
Assistant Professor,
PIMS - Panipat

2.  Diuretics is an agent which increase
urine and solute.it may be classified
as follows:
 1. HIGH EFFICACY DIURETICS
 Furosemide,azosemide,
bumetanide,piretanide,torsemide.
 2.MODERATE EFFICACY DIURETICS
 THIAZIDES
 Benzothiadiazines –
chlorothiazide,hydrochlorothiazide,
 polythiazide

3.  THIAZIDE RELATED AGENT
 Chlorthalidone,clopamide,
 indapamide,metolazone,xipamide.
 3.LOW EFFICACY DIURETICS
 POTASSIUM SPARING DIURETICS
 Triamterene,amiloride,spironolactone.
 CARBONIC ANHYDRASE INHIBITOR
 Acetazolamide,methazolamide,
 dorzolamide

4.  OSMOTIC DIURETICS
 Mannitol,urea,glycerol
 METHYLXANTHINE
 Theophylline
 4.NEWER AGENT
 Vasopressin antagonist –
conivaptan,tolvaptan,lixirvapta
n.

5.  Loop diuretics act on the
ascending limb of the loop of
henle.frusemide is the most
commonly used diuretics.it is a
sulphonamide derivative.it is a
powerful diuretics.

6.  Frusemide acts by inhibiting NaCL
reabsorption in the thick ascending limb
of the Henles loop.it blocks the Na K
2CL symporter in the loop.it greatly
increase the excretion of Na and CL in
the urine.as large amount of NaCL is
absorbed in this segment. Diuretic
response increases with dose and over
treatment may cause dehydration.

7. In Loop of Henle
Frusemide inhibits Na Cl reabsorption
Increase the excretion of Na & Cl in urine
Leads to increased urinary output
In Loop of Henle
Frusemide inhibits Na Cl reabsorption
Increase the excretion of Na & Cl in urine
Leads to increased urinary output

8.  Frusemide is also a weak carbonic
enhydrase inhibitor hence it increase
the excretion of HCO3 and
phosphate.
 PHARMACOKINETICS
 Frusemide is rapidly absorbed orally,
highly bound to plasma
proteins,metabolized in the liver and
excreted by kidneys.IV it acts in 2-5
minutes,oral it takes
 20-40minutes.

9.  BUMETANIDE
 Is a sulfonamide like Frusemide but
it is 40 times more potent than
Frusemide.
 TORSEMIDE
 Is longer acting and can be given
once a day.
 ETHACRYNIC ACID
 Is more likely to cause adverse effect
ototoxicity and is not commonly used.

10.  Hyperkalemia and metabolic
alkalosis
 dehydration,
 hypotension
 Hyperuricemia,hypocalcemia,
 Hypomagnesemia,ototoxicity,
 Hyperglycemia,skinrashes,
 nausea,vomitting,hypotension,
 Weakness.

11.  Edema
 Acute renal failure
 Acute pulmanary edema
 Cerebral edema
 Forced diuresis:in poisoning due
to drug like barbiturates and
salicylates, Frusemide is used
with IV fluids.
 Hypertension with renal
impairment

12.  Chlorthiazide was the first thiazide to be
synthesized.
 Mechanism of action
 Thiazide act on the early distal tubule.it
have a moderate efficacy 90% of the filtered
sodium is already reabsorbed before
reaching the distal tubule.they also inhibit
carbonic anhydrase activity and increase
bicarbonate loss.it also enhance excretion of
Mg and K .But they inhibit urinary
excretion of Ca and uric acid resulting in
hypercalcemia and hyperuricemia.

13. In early distal tubule
inhibit carbonic anhydrase activity and increase bicarbonate
loss
Enhance excretion of Mg and K and Inhibit urinary excretion
of Ca and uric acid
Leads to increased urinary output
In early distal tubule
inhibit carbonic anhydrase activity and increase bicarbonate
loss
Enhance excretion of Mg and K and Inhibit urinary excretion
of Ca and uric acid
Leads to increased urinary output

14. Thiazides are well absorbed
orally and are rapid
acting.they are excreted by
kidney.
Hyperkalemia,hyperuricemia,
hypotension,hyperglycemia,
GIT disturbance,allergic
reaction.

15. Hypertension
Congestive heart failure
Edema
Renal stones
Diabetes insipidus

16. Example of potassium sparing
diuretics is Spironolactone it is an
aldosterone antagonist,

17.  It may act two ways .they may be
aldosterone antagonist or directly
inhibition of channels in distal tubes
and collecting duct.
 Major amount of Na is reabsorbed is
proximal parts. It also reduces K
loss

18. Potassium sparing diuretics
Na is already Reabsorbed in proximal parts.
Reduces K Loss.
Enhances the Ca excretion
Increases the Urinary Excretion
Potassium sparing diuretics
Na is already Reabsorbed in proximal parts.
Reduces K Loss.
Enhances the Ca excretion
Increases the Urinary Excretion
Ald0sterone
Antagonist
Inhibition of channels in
Distal Tubules &
Collecting Duct

19.  Mannitol is an osmotic diuretics.
 Given in IV (Orally Not Absorbed), it gets
filtered by the glomerulus but not
reabsorbed.
 It causes water to be retained in proximal
tubule and descending loop of Henle, by
osmotic effect resulting in water diuresis.
 There is also some loss of sodium.

20.  Increased Osmotic Pressure in Proximal
Tubule
 Decreased Water reabsorption
 Increased Urine Excretion

21.  To maintain urine volume and prevent
oliguria (Decreased Urine Output)
 To reduce ICP and IOP following
head injury and Glaucoma
respectively.