Diuretics

1. SCHOOL OF PHARMACEUTICAL SCIENCES
SIKSHA ‘O’ ANUSANDHAN (DEEMED TO BE UNIVERSITY)
PRESENTED BY
RANDEEP PATRO
M.PHARM(1ST SEM)
PHARMACOLOGY

2. What are diuretics ?
These are the drugs or agents which promotes diuresis i.e increased urine
production and increased rate of urine flow .
.

3. Physiology of urine formation…..

5. Proximal convulated tubule
Normal Function :
 Glucose, bicarbonate, amino acids
and other metabolites are reabsorbed
 Water follows passively
to maintain iso-osmolarity .
 Large amount of HCO3
- ,
amino acids, acetates create
driving force for Cl –
to diffuse
through paracellular pathway.
 95% of Na+ is reabsorbed actively .

7. ACETAZOLAMIDES
MOA :
Inhibits bicarbonate reabsorption and reduces Na+ H+ exchange and
NaHCO3 excretion with water .
Uses :
 Treatment of epilepsy
 Treatment of UTI
 Decrease CSF production and prevents motion sickness.
 Increases the production of aqueous tumor by reducing intra occular
pressure (Glucoma)
Adverse Effects :
 Contineous use of these drugs decreases HCO3
- conc. In the body and
causes acidosis ,less HCO3
- is filtered
 Liver cirrhosis
 Hypokalemia
 Hypersensitivity reactions like fever and rashes
Drugs acting on PCT

8. loop of henle
Normal Function :
At DLH water is reabsorbed
At thick ALH Na+/K+/2Cl- symport is carried out

10. FRUSEMIDES
MOA :
 Inhibits Na+/K+/2Cl- symport
 Increase excretion of Ca+2 and mg +2
 Decrease excretion of uric acid
 Increase renal blood flow and PGE2 synthesis(vaso dilation)
Uses :
 Acute renal failure
 Treatment of CHF, renal failure, pulmonary edema
 Treatment of barbiturate poisoning
Adverse Effects :
 Alkalosis
 Muscle cramp, Dizziness, Confusion, Nausea
 Cardiac Arrest(Hypotention)
 Hypersensitivity reactions like skin rashes
Drugs acting on LOH

11. Distal convulated tubule
Normal Function :
Na+
- Cl-
cotransport is carried out

13. CHLOROTHIAZIDES
Drugs acting on DCT
MOA :
 Binda to Na+
- Cl-
cotransport and change the confirmation
 Increase excretion of K+ and uric acid
 Long term use causes excretion of mg+2
Uses :
 GIT disturbances
 Prevention of stone formation (decrease in deposition of mg+2
and Ca+2)
 Treatment of diabetes insipidus
Adverse Effects :
 Gout
 CNS disturbances
 Gitelman’s syndrome (deficiency of mg+2
)

14. Collecting duct
Normal Function :
Na+
- Cl-
cotransport is carried out
Blocks epithelial Na+
channels (ENaC)

16. SPIRONOLACTONES &
AMILORIDES
MOA : (DCT & CD)
 Aldosterone antagonism
 Inhibit renal epithelial Na+
channels
Uses :
 Treatment of CHF
 Treatment of edema
Adverse Effects :
 Menstural Failure
 Hyperkalemia
 Photosensitivity reactions
Drugs acting on cd

17. OSMOTIC DIURETICS
MOA :
 Retains water isosmolarity in PCT and dilutes luminal fluid
which opposes NaCl reabsorption and Na+
excretion increases.
 At LOH increases the ECF vol. and increases renal blood flow
by reducing
 Decreases passive absorption of Na+
from acending limb.
Uses :
 Treatment of acute renal failure
 Treatment of chronic edema
Adverse Effects :
 Chest pain
 Nausea, vomiting, headache
 Photosensitivity reactions like rashes

18.  Patients with known drug hypersensitivity and with electrolytic
imbalance .
 Should be given carefully to anyone with renal dysfunction, as change in
blood flow and kidney perfusion may cause diseased kidney .
 It also have glucose elevating effect should not be given to diabetes
mellitus .
 Patients with liver diseases which may interfere with drug metabolism
and lead to toxicity .
 Should not be given in Pregnancy .
Cautions and contraindications
• NSAIDs – Increases risk of renal failure
• Corticosteroids – Increases loss of k+
• Digitalis – Increased potential for digitalis causing toxicity
• Anticonvulsants – Phenytoin reduces diuretic effects of frusemide
• Antidiabetic agents – Loss of diabetic control
• Probenicid – To block uric acid retention
Drus interactions