PHARMACEUTICAL CHEMISTRY what is GIT all gastrointestinal agents examples of each antacids saline cathartics

1. 3.GASTROINTESTINAL
AGENT
Prepared By: Priya D. Yannawar
(M Pharm)

2. CONTENT
• Introduction
• Acidifying Agent
• Antacid
• Protectives And Adsorbent
• Saline Cathartics (Laxative)

3. Introduction
Gastro Intestinal Track (GIT) :
 It is a track from mouth to anus which includes all organs of digestive system in humans.
 The organ includes,
 Mouth
 Pharynx( throat)
 Esophagus
 Stomach
 Small intestine
 Large intestine
 Rectum
 anus

4. CONTINUE..

5. • Gastrointestinal Agent
• Definition:
The pharmaceutical compounds used in treatment of gastrointestinal disorder are known as
gastrointestinal agent.
• Some of gastrointestinal agent are;
1. Acidifying Agent
2. Antacid
3. Protective And Adsorbent
4. Saline Cathartics (laxative)

6.  Gastrointestinal Agent
• Gastrointestinal Agent With Example:
Acidifying agent Antacid Protective and
adsorbent
Saline cathartics
Dilute hydrochloric
acid
Sodium bicarbonate Bismuth
subcarbonet
Sodium potassium tartrate
Aluminum hydroxide gel kaolin Magnesium sulphate
Aluminum phosphate
Calcium carbonate
Magnesium carbonate
Magnesium trislicate
Magnesium oxide and
combination of antacid
preparation

7. • Acidifying Agent
• Definition: Drugs That Increases Acidity Are Called Acidifying Agent.
• Hydrochloric acid and other enzyme required for digestion is secreted by epithelial cells of gastric mucosa.
Which helps in soften fibrous food and helps in digestion. The stomach pH varies from 1 to 7.
• HCL also helps in formation of pepsin from pepsinogen at acidic pH and kills harmful bacteria in ingested
food.
• if there is no secretion of hydrochloric acid in gastric secretion the condition is called as achlorhydria.
• Symptom:
• Mild diarrhea
• Abdominal pain
• Sensitivity to spicy food
• Loss of appetite.
• In some patient which are suffering from carcinoma of stomach, chronic gastritis, there is a total
achlorhydria and hence for such patient hydrochloric acid or acidifying agents are given.

8. • Dilute Hydrochloric Acid
• Properties of HCL;
• Color: colorless fuming liquid
• Odor: pungent
• Solubility : it is miscible with water, alcohol
• Specific gravity: 1.18
• Dilute acid contain weight 10% w/w of HCl.
• It is given in 5 ml dose after diluting with 200 ml water in order to avoid its harmful effect in teeth. And dilute
solution can be ingested using straw to avoid exposure of dental enamel with HCl.

9. continue
• Uses: in treatment of achlorhydria.(Dose: 2 to 5 ml diluted with 200to 250 ml of cold water)
• It is used as solvent in many industries.
• It is also used as laboratory reagent.
• It is also used in treatment of metabolic acidosis.
• Storage: stored in stoppered container of glass or other inert material, below 30 degree C.

10.  ANTACID
• Antacids are the drugs that neutralize the excess hydrochloric acid in the body which may cause
pain, ulceration in GIT.
• Effectiveness of antacid is measured in neutralizing capacity.
• This drugs relieve pain due to hyperchlorhydria.
• Hyperacidity or hyperchlorhydria; due to inflammation of gastric mucosa as in gastritis, there is
hypersecretion of hydrochloric acid which is called as hyperchlorhydria.
• And this condition sometimes leads to peptic ulcer. Depending upon the portion where erosion
of mucosal layer results, it is known as esophageal ulcer, gastric and duodenal ulcer.
• Treatment: anticholinergic drugs, diet, antacids.

11.  Ideal Properties of Antacids
 It should not be insoluble in water and should have fine particle size.
 It should produce its effect gradually and over longer period of time
 Is should not have any side effect.
 It should be stable.
 It should buffer in pH range 4-6.
 Reaction between antacid and gastric HCl should not produce large volume of gas.
 Is should no act as laxative or cause constipation.

12.  Types Of Antacid
Systemic antacid Non systemic antacid
It is soluble in water and systemically
absorbed
Insoluble in water and systemically not
absorbed
Capable of producing systemic alkalosis React with HCl in stomach to form
corresponding salt
Ex .sodium bicarbonate, insoluble potassium
citrate
Ex. aluminum hydroxide gel

13. • Antacid are further divided into following
1. Aluminum Containing Antacid:
• Aluminum Hydroxide Gel, Aluminium Phosphate
2. Magnesium Containg Antacid:
• Magnesium Trisillicate, Magnesium Oxide, Magnesium Carbonate
3. Calcium Containing Antacid:
• Calcium Carbonate.
4. Combination Of Antacid Preapation:
• Aluminum Hydroxide And Magnesium Hydroxide Gel
• Calcium Carbonate Contaning Antacid Mixtures.

14. • Sodium Bicarbonate
• Synonym: baking soda, metha soda.
• Chemical formula: NaHCO3
• Mol.Wt: 84.01
• Preparation:
• Prepared by solvay process or ammonia soda process.
• Brine solution(NaCl) is saturated with ammonia to remove traces of impurities solution is filtered
and heated at 30 degree c.
• Then it passed trough carbonating tower and meet ascending current of carbon dioxide.
• NaHCO3 is less soluble in water below 15 degree c the precipitate is filtered and dried.

15. CONTINUE.
• H2O + CO2 H2CO3
carbonic acid
• NH3 + H2CO3 NH4CO3
ammonium carbonate
• NaCl+ NH4CO3 NaHCO3+ NH4CL
ammonium carbonate

16. • properties:
• Color : whit crystalline powder
• Taste: saline
• Solubility: soluble in water and insoluble in alcohol
• Storage: store in well closed container.

17. • Uses:
• Antacid
• Treatment of systemic acidosis
• Used in effervescent mixtures, alkaline solution and douches.
• Used in treatment of vomiting in children.
• Used in eye lotion and as ear drop to soften and remove wax
• As rinsing solution for contact lense.
• Used as vaginal douches

18. • Aluminum Hydroxide Gel
• Mostly used antacid. Aluminum hydroxide gel
• It is used in 3 forms dried aluminum hydroxide gel
dried aluminum hydroxide tablet
• Properties:
Color; white amorphous powder
Taste; tasteless
It is white viscous suspension of hydrated aluminum oxide having varying amount basic
aluminum carbonate.
Preparation contain methyl oil, peppermint oil, sucrose, saccharin as sweetening and flavoring
agent.

19. CONTINUE..
• Preparation;
• Hot solution of potash alum mix 3 Na2CO3 + 2 KAl ( SO4) + 3H2O
constant stirring sodium carbonate potash alum
• Hot solution of sodium carbonate
CO2 removed completely 3Na2SO4 + K2SO4 + 2 Al ( OH)3 + 3 CO2
• ppt of aluminum hydroxide
• Filter
• ppt washed with hot water

20. CONTINUE;;
• Chemical Properties:
• Aluminum hydroxide gel gives astringent aluminum chloride when it react with gastric HCL which results in
nausea, vomiting, constipation.
• Al(OH)2 + 3HCL AlCl3 + 3H2O
astringent aluminum chloride
• Uses:
 Gastric antacid
 Diarrhea and cholera treatment
 Used externally as mild astringent and desiccant.
 Used as antiperspirant and dentifrices.
 Absorb toxin
 Used in peptic ulcer and hyperchlorhyria treatment
• Dose:
 Aluminum hydroxide gel: 7.5- 15 ml.

21. • Magnesium Oxide light magnesium oxide
heavy magnesium oxide
• Chemical formula: MgO
• Mol wt. : 40.30
• Physical properties :
• Color; white
• Odor; odorless
• Taste; alkaline
• Solubility; practically insoluble in water and alcohol. Soluble in dilute acid.
• Preparation
• It is prepared by heating the respective magnesium carbonate to white in an oven.
• 3MgCO3 + Mg(OH)2. 3H2O 6 MgO + 12 H2O + 3 CO2

22. • CONTINUE
• Chemical properties
• 6MgO + 12 H2O 6Mg(OH)2 + 6H20
milk of magnesia
• Uses:
Potent antacid and mild laxative
For liquid preparation light magnesium oxide is used
For powder and tablet preparation heavy magnesium oxide is used
Used in Dentifrices
Dose:
• 0.3 to 0.6 gm

23. • Calcium Carbonate( Precipitated Chalk)
• Chemical Formula: Caco3
• Mol. Wt.- 100
• Physical Properties:
• Color; White
• Odor; Odorless
• Taste; Tasteless
• Texture; Microcrystalline
• Solubility: Practically Insoluble In Water
• It occurs as chalk, limestone, marble, aragonite, calcite, chief constituent of shells, corals.
• preparation:
Na2CO3 + CaCl2 CaCO3 + 2 NaCl
Sodium calcium ppt
Carbonate chloride

24. CONTINUE..
• Chemical properties:
• CaCO3 + 2HCl CaCl2+ CO2 + H2O
• Uses
Non systemic antacid
Used as chalk
Relive pain of gastric and duodenal ulcer
Treatment of diarrhea, polishing agent in tooth powder
• Dose:
• 1- 5 gm daily according to need

25. • Combination Of Antacid Preparation
• There are number of preparation containing combination of antacid are available in market.
• This are given in combination to decrease side effect of each other and give easier onset of action.
• Ex. Al.Hydroxide gel in combination with Mg(OH)2 and hence magnesium salt cause dirrhea and
aluminum compound produce constipation by combining both, these undesirable actions are
balanced.
• Magnesium trisilicate oral powder
• It contains
• Magnesium trisillicate
• Chalk powder
• Sodium carbonate
• Heavy magnesium carbonate…. Each 250 mg

26. • Protective And Adsorbent
• This are chemical agent used internally in treatment of disturbance of GI tract.
• It forms protective layer on painful ulcers, and hence protective and adsorbent adsorbs
bacteria.
• They are insoluble salt and form coating on mucosal membrane and provide mechanical
protection.
• The protective and adsorbent activity increases as particle size decreases ( it provide large
surface area for protection and adsorbent.
• Properties:
• Insoluble
• Chemically inert

27. • BISMUTH SUB CARBONATE
• Mol formula: (BiO2)2(CO3)2. 2 H2O
• Properties
• Color- white
• Odor- odorless
• Taste- tasteless
• Solubility- insoluble in water and alcohol
• Uses :
• Protective and adsorbent
• Good adherence to skin and mucus membrane make it valuable as adsorbent
• Antidirrahoel
• Used in lotion and face powder
• Used as antacid

28. • KAOLIN( HYDRATED ALUMINUM SILICATE)
• Chemical Formula: AI2O3.2SiO2.2H2O
• Properties:
• Color- White
• Odor- Odorless
• Taste- Tasteless
• Solubility- Insoluble In Water, Mineral Acid
• Preparation
• Prepared from natural substance by electrical sedimentation.

29. CONTINUE
• USES
• Intestinal adsorbent in various enteritis
• Externally used as dusting powder and as ingredient of toilet powders
• Used as drying agent for moist sores and infections
• Ex. Weeping ulcers
• Clarifying agent

30. • SALINE CATHARTIC'S
• This are agent which induce defecation, quickened and increase evacuation from bowls. Laxative are
mild cathartics.
• It also increase fluidity of intestinal content, by retention of water.
• Cathartic's and purgative generally act by 4 mechanism.
stimulant( act by brining stimulation of peristaltic activity by local irritation
on intestinal wall. ex. Senna, castor oil
bulk purgative( increase bulk of intestinal content and this increased bulk
stimulate peristalsis, ex. Isapgol, methyl cellulose
mechanism
lubricant: act as lubricant and bring smooth clearance of faecal material
ex. Liquid paraffin, glycerin
saline cathartic's; increase osmotic load of intestine by absorbing large
quantity of water and hence stimulate peristalsis.
ex. Magnesium, sulphate salt

31. • MAGNESIUM SULPHATE
• Chemical formula; MgSO4.7 H2O
• Molecular weight; 246.47
• Properties;
• Color- colorless crystals
• Taste- bitter, saline
• Solubility- soluble in water
• Preparation
MgCO3 + H2SO4 MgSO4 + H2O + CO2
magnesium hydrochloric magnesium
carbonate acid sulphate

32. continue.
• Uses
• Saline cathartic's
• Anticonvulsant
• Used orally as antidote for heavy metal poisoning
• Treatment of cholecystitis ( inflammation of gall bladder ) hypertension, lower intracranial
pressure, wet dressing for carbuncles( infection of hair follicle)
• Used for local inflammation and infected wounds.