Basics Of Pharmacy

Wednesday, January 24, 2024

Basics Of Diuretics

 DIURETICS

Diuretics are substances which help to increase the urination & remove excessive fluid & salts from the body.

Diuretics also help to lower the blood pressure & are used in medical conditions which are due to excessive fluid.Diuretics are also known as water pills.

In simple words diuretics are the Drugs/medications that produce a state of high urine flow.


OVERVIEW

Normally, diuretics tend to secrete a high amount of Sodium and ions alongside water through urination. Due to this capability, they are named among the First Line of Treatment of Hypertension.

Besides this, they are used in the treatment of Cardiovascular Events (CVEs) and Edema. 

In this article we will discuss following,

  • Normal Physiology of Nephron 

  • MOA of Diuretics

  • Classification Of Diuretics 

  • Drugs MOA, Therapeutic Uses & Side Effects

  • Diuretic Resistance

  • Prevalence

  • Case study

  • Combination Therapy

  • Overall Side Effects

  • Important Points


Diuretics

NORMAL PHYSIOLOGY OF NEPHRON


Bowman's capsule performs the filtration of blood plasma (16%-20%) through capillaries. Filtrate buildup of glucose, electrolytes (k+, Na+, Cl-), sodium bicarbonate, and amino acids reabsorbed into the blood from the lumen.So

Regulation of 

  • urine volume

&

  • iconic composition 

is held by five zones of the nephron in the kidney. 


These functional zones are as follow,

  1. Proximal convoluted tubule (PCT)(67% reabsorption of Na)

  2. Descending loop of Henle 

  3. Ascending loop of Henle (25% reabsorption of Na)

  4. Distal Convoluted Tubule (DCT)(5% reabsorption of Na)

  5. Collecting Tubule and Duct (1% reabsorption of Na)


PCT and DCT are present in the cortex part of the nephron while other zones are present in the medulla.


MOA OF DIURETIC


Diuretics mechanism of action is simply prescribed as ‘the inhibition of Na and water reabsorption from the lumen to blood’


 Note

All diuretics act differently according to their mechanism.


CLASSIFICATION   Of Diuretics 


Diuretics are divided into five categories according to different nomenclature. These drugs are more defined to act at different sites of a nephron.

       

  1. Loop Diuretics 

  2. Thiazide Diuretic

  3. Potassium Sparing Diuretic 

  4. Carbonic Anhydrase Inhibitor 

  5. Osmotic Diuretics                                         


LOOP DIURETICS


Normal Physiology of Nephron

In normal physiology of nephrons at the Ascending loop of Henle 25% of Na, Cl & k are reabsorbed from lumen to blood through Na & cl ion co-transporter. 


Mechanism Of Action Of Loop Diuretics 

Loop diuretic act as to inhibit the Na, Cl & K Co transporter pump and reabsorption of these ions does not take place. 

As a result, these ions are excreted within water in large volumes of urine.


Drugs of Loop of Henle

It includes following drugs,


  1. Bumetanide

  2.  Furosemide

  3.  Torsemide 

  4. Ethacrynic acid


Therapeutic Uses

Following are therapeutic uses

  1. Edema

  2.  Hypercalcemia

  3.  Hyperkalemia


Side effects

It includes 


  1. Ototoxicity

  2.  Hypotension 

  3. Hypokalemia


THIAZIDE DIURETIC


Normal Physiology of Nephron

In normal physiology at distal convoluted tubules Na & Cl go into blood and Calcium into urine.


Mechanism Of Action Of THIAZIDE Dietetics 

Thiazide controls the reabsorption of Na and Cl 5% by inhibiting the pump thus increased excretion of Na & Cl occurred.These drugs also have a vasodilation effect.Calcium reabsorbed occurred by thiazide diuretics.


Drugs of Thiazide

It includes 


1.Chlorothiazide 2.Hydrochlorothizide 3.Indapamide

4.Metolazone

5.Chlorthalidone


Therapeutic Uses

It includes 

  1. Hypertension

  2. Heart failure

  3.  Hypercalciuria


Side effects

It includes 

  1. Hypokalemia

  2. Hypomagnesemia 

  3. Hypovolemia


CARBONIC ANHYDRASE INHIBITORS:


Normal Physiology of Nephron

In normal physiology, the carbonic anhydrase enzyme is responsible for the reabsorption of bicarbonate.These Act on the proximal convoluted tubules.


Mechanism Of Action OF Carbonic Anhydrase Inhibitors

In a drug situation, bicarbonate is not reabsorbed and is lost in the form of sodium bicarbonate from blood to urine.Hence large amounts of urine excrete.


Drugs of CAI

It includes 

  1. Acetazolamide


Therapeutic uses Of CAI

It includes

  1. Glaucoma

  2. Altitude Sickness 


Side effects

It includes

  1. Drowsiness

  2. Metabolic acidosis 

  3. Renal stone formation


POTASIUM SPARING DIURETICS


Normal Physiology of Nephron

In normal physiology at collecting tubule, the reabsorption of Na along with excretion of K+ ions occurred.


MOA Of Potassium Sparing Diuretics 

Potassium-sparing diuretics act on the collecting tubule, having a strong property of antagonizing the aldosterone receptor. Thus, Na+ moves outside the body in the form of urine and K+ moves backward to blood to retain in the body.


Drugs Of Potassium Sparing Diuretics

It includes

  1. Spironolactone 

  2. Eplerenone


Therapeutic uses

It includes

1.Resistance Hypertension 2.Polycystic Ovary Syndrome 

           3.Heart failure


Side effects

It includes : 

  1. Drowsiness

  2. Metabolic acidosis 

  3. Renal stone formation


OSMOTIC DIURETICS


Normal Physiology of Nephron

In normal physiology, the descending loop of Henle reabsorbs the amount of Na as well as Ca+ and Mg due to high blood concentration.


Mechanism Of Action Of Osmotic Diuretics 

Osmotic diuretics act on the descending loop of Henle and prevent the reabsorption of water. Thus reduce the plasma volume also and conduct the elevated excretion of Na, K+, Mg, Ca+. Precisely, these drugs enhance the solute concentrations in the tubular lumen to retain the water in tubules.


Drugs Of Osmotic Diuretics

It includes

  1. Mannitol 

  2. Urea


Therapeutic uses

 It includes

  1. Acute Glaucoma 

  2. It helps patients with increased intracranial pressure


Side effects

 It includes

  1. Dehydration

  2.  Hyponatremia 


DIURETIC RESISTANCE


Diuretic resistance is defined as the inability to reduce edema even if the dose is provided to its maximal or therapeutic level. The main causes of resistance to diuretics are 

  1. Poor adherence to drug

  2. Elevated level of Na+ Reabsorption

  3. Pharmacokinetic problems 


PREVALENCE


It is estimated that between 20% and 30% of HF patients have diuretic resistance (DR).


CASE STUDY


A case study results showed that increased usage of antihypertensive drugs with diuretics causes the arousal of renal cell cancer in white people. Added to more conclusions, the elevated duration of usage of Diuretics leads to an increased risk of renal cancer cells.


COMBINATION THERAPY


Practitioners prescribed diuretics as combination therapy for treating diseases such as Hypertension and Heart Failure patients.


OVERALL SIDE EFFECTS


Side effects of diuretics may count as 

  • Stomach upset known as Indigestion 

  • Hair Loss

  • Dizziness

  • Nausea

  • Headache 

  • Muscle Cramps

  • Dehydration

  • Breast Enlargement

 

IMPORTANT POINTS


In a short way, some important points must be remembered related to diuretics,


  • All diuretics result in excretion of K+ except Potassium Sparring Diuretic

  • Potassium Sparring Diuretics may induce Gynecomastia

  • Furosemide (Loop Diuretic) is used only in an Emergency situation

  • Calcium Reabsorption results in the action of Thiazide Diuretics.

  • Weakest Diuretic action performed by the Carbonic Anhydrase Inhibitors

  • The most powerful action of diuretics is shown by the Loop Diuretics.


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Friday, September 2, 2022

Basic Knowledge and Types Of Receptors

Receptors are macromolecules which play a vital role in chemical signalling within and between cells. Receptors can be found on the surface of a cell membrane or deep within the cytoplasm. The cellular Biochemical processes are controlled by activated receptors directly or indirectly for example ion conductance, protein phosphorylation, DNA Transcription, and Enzymatic activity.

Monday, August 22, 2022

Learn Basic Pharmacology Through MCQs

Q :1

_____Is known as pharmacokinetics?


 a) The knowledge of Absorption, Distribution Metabolism, and Excretion of Drugs

 b)The study of new Drug-Drug Development

 c) The study of Distribution, absorption, Metabolism, and Excretion of drugs

Thursday, April 14, 2022

Basic Pharmacology Of Autacoids

Q:1

The CNS consists of which of the following?


a)Brain

b)Spinal Cord

c)Both a & b


The Correct Answer is (c)


Q:2

The PNS consists of which of the following?


a)ANS

b)Somatic Nervous System

c)Both a & b

d)None of the above


The Correct Answer is (c)


Q:3

ANS consists of which of the following?


a)Sympathetic Nervous System

b)ParaSympathetic Nervous System

c)Both a & b

d) None of the above


The Correct Answer is (c)


Q:4

ANS controls which of the following?


a)Voluntary Activities

b)Involuntary Activities

c)Both a & b

d) None of the above


The Correct Answer is (b)


Q:5

Drugs affecting CNS may produce?


a)Anesthesia

b)Sedation

c)Relief Pain

d)All of the above


The Correct Answer is (d)


Q:6

Which of the following deals with fight or flight situations?


a)Sympathetic Nervous System

b)ParaSympathetic Nervous System

c)Somatic Nervous System

d)All of above


The Correct Answer is (a)


Q:7

Which of the following is true about Autacoids?


a)Have a short duration

b)Have a long duration

c) Both a & b


The Correct Answer is (a)


Q:8

An example of Autacoids is?


a)Prostaglandin

b)Kallidin

c)Histamine

d)All of above


The Correct Answer is (d)


Q:9

In the human body, prostaglandins are produced from?


a)Propionic Acid

b)Arachidonic Acid

c)Pantothenic Acid

d)All of the above


The Correct Answer is (b)


Q:10

Prostaglandin is produced by the enzyme?


a)Cyclooxygenase

b)Cellulase

c)Phospholipase

d)None


The Correct Answer is (a)


Q:11

Which of the following are functions of Prostaglandin?


a)Inhibit Platelet Aggregation

b)Contract Uterine smooth muscles

c)Inhibit Gastric Acid Secretion.

d)All of above


The Correct Answer is (d)


Q:12

Which of the following are isoforms of COX?


a)COX-1

b)COX-2

c)COX-3

d)a&b


The Correct Answer is (d)


Q:13

Which of the following types of NSAIDs should not be used in children with influenza type viral infections?


a)Salicylate

b)Acetic Acid derivatives

c)Propionic Acid Derivatives

d)Oxicams


The Correct Answer is (a)


Q:14

 Which of the following is a non-purine analog?


a)Probenecid

b)Febuxostat

c)Serotonin

d)Colchicine


The Correct Answer is (b)


Q:15

Gout is an inflammatory response to the accumulation of?


a)Sodium Urate Crystals

b)Calcium Urate Crystals

c)Potassium Urate Crystals

d)Magnesium Urate Crystals


The Correct Answer is (a)


Q:16

 Which of the following is a good choice to treat gout?


a)Tolmetin

b)Oxaprozin

c)Celecoxib

d)Aspirin


The Correct Answer is (b)


Q:17

 Which of the following is used to treat chronic tophaceous gout?


a)Tolmetin

b)Oxaprozin

c)Colchicine

d)Probenecid


The Correct Answer is (d)


Q:18

Side effects of Probenecid may include?


a)Rashes

b)Kidney Stone

c)GI Irritation

d)All of the above


The Correct Answer is (d)


Q:19

Probenecid is an example of?


a)Salicylate

b)Acetic Acid derivatives

c)Propionic Acid Derivatives

d)Benzoic acid derivatives


The Correct Answer is (d)


Q:20

 Which of the following is used to treat gouty arthritis with hyperuricemia?


a)Probenecid

b)Colchicine

c)Febuxostat

d)Allopurinol


The Correct Answer is (c)


Q:21

Stevens-Johnson syndrome may be associated in rare cases with the use of?


a)Probenecid

b)Colchicine

c)Febuxostat

d)Allopurinol


The Correct Answer is (d)


Q:22

Leukotrienes are 20 carbon derivatives of?


a)Proteins

b)Phospholipid

c)Fatty Acid

d)Glycoprotein


The Correct Answer is (c)


Q:23

Serotonin is synthesized from?


a)Amino acid

b)Phospholipid

c)Fatty Acid

d)Glycoprotein


The Correct Answer is (a)


Q:24

Which of the following is 5 HT?


a)Histamine

b)Leukotriene

c)Prostaglandin

d)Serotonin


The Correct Answer is (d)


Q:25

Ergot alkaloids are derived from?


a)Bacteria

b)Fungus

c)Viruses

d)None of the above


The Correct Answer is (b)


Q:26

Ergotamine is used to treat migraine & acts by?


a)5- HT 1

b)5- HT 2

c)5- HT 3

d)5-HT 5


The Correct Answer is (a)


Q:27

Histamine is derived from?


a)Histidine

b)Histine

c)Protein

d)Tyrosine


The Correct Answer is (a)


Q:28

Concentration of histamine is high on which of the following?


a)Basophils

b)Mast Cells

c)Neutrophils

d)a&b


The Correct Answer is (d)


Q:29

Which of the following generations of Antihistamines cause sedation?


a)1st Generation

b)2nd Generation

c)3 Generation

d)None of above


The Correct Answer is (a)


Q:30

Which of the following is an example of 2nd generation Antihistamines?


a)Fexofenadine

b)Loratidine

c)Cetirizine

d)All of the above


The Correct Answer is (d)


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