1 / 50

Gastrointestinal Agents ( GIA)

Gastrointestinal Agents ( GIA). Inorganic agents used to treat GIT. Inorganic agents used to treat gastrointestinal disorders include: Products for altering gastric pH -Acidifying Agents: Used to treat achlorhydria (absence of HCl in the gastric secretion) e.g.- Diluted HCl

kallima
Download Presentation

Gastrointestinal Agents ( GIA)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Gastrointestinal Agents ( GIA)

  2. Inorganic agents used to treat GIT • Inorganic agents used to treat gastrointestinal disorders include: • Products for altering gastric pH • -Acidifying Agents: Used to treat achlorhydria (absence of HCl in the gastric secretion) • e.g.- Diluted HCl • -Antacids: Used to treat hyperchlorhydria and peptic ulcer. • 2) Protectives for intestinal inflammation • 3) Adsorbents for intestinal toxins • 4) Cathartics or laxatives for constipation

  3. Acidifying Agents • Achlorhydria is the absence of HCl in the gastric secretion. Lt is common in otherwise normal individual after age 50 years. • Gastric HCl functions by killing the bacteria in ingested food& drink, softening fibrous food, promoting formation of the proteolytic enzyme, pepsin.

  4. The symptoms of achlorhydria • 1-mild diarrhea( frequent bowel movement) • 2-epigastreic pain ( upper abdominal pain ). • 3- sensitive to food ( spicy ).

  5. Treatment of Achlorhydria • Dilute HCl solution ( 200ml ) prepared . • Dose 15ml for each . • The use of dil HCl because to avoid exposure of dental enamel

  6. Antacids • Agents are given or administered to neutralize excess HCl which may be causing pain & possible ulceration.

  7. When anatcids are described? • 1- uncomfortable feeling from over eating • 2-heartburn • 3-A growing hungry feeling between meals.

  8. Treatment of hyperacidity • 1- Anticholinergic agents. • 2- Inorganic antacids ( Aluminum hydroxide and Magnesium hydroxide ). • 3-In case of ulceration, H2 –antagonist • Cimetidine, Ranitidine, … • 4-Bed rest • 5- Surgical if necessary ( Bleeding ).

  9. Hyperacidity developed , the result can range from gastritis ( inflammation of gastric mucosal to peptic ulcer.A peptic ulcer can be located in the lower end of the esophagus. • Also, stomach ulcer( gastric ulcer), duodenum ulcer.

  10. Patients suffering from burn, which is due to gastric acid entering the esophagus either a blechor upon lying in bed ( Reflux ). • Frequently, these people obtained relief by sleeping in a bed elevated at the head to reduce the flow of gastric fluid from the stomach into esophagau.

  11. Types of peptic ulcers • There are TWO types. • 1- chronic ulcer. • 2- acute ulcer. • Chronic ulcer rather than acute , • Complications will include hemorrhage , may be leads to other disease ( CA).

  12. Treatment of Ulcer • Range from diet • Antacids • Anticholinergic agents.

  13. Antacids Therapy • Antacids are alkaline bases used to neutralized the excess gasrtic HCl associated with gastric & peptic ulcers.

  14. Antacids Products( drugs) • * Sodium bicarbonate Na2HCO3 • **Aluminum antacid products • *** Magnesium antacid products. • Combination therapy( Al + Mg) products. • Maloox . • There is no ideal antacids

  15. Selection of pharmaceutical Anatcids • The antacid should not be absorbable or cause systemic alkalosis. •  It should not be laxative or cause constipation •  It should buffer in the pH 4-6 range •  It should be rapidly effective and maintain its effect over a long period of time. •  It should probably inhibit pepsin but should not completely inactivate peptic digestion. •  It should not produce rebound acidity or excessive eructation (belching). •  It should not cause large evolution of gas by reacting with gastric HCl. •  It should not affect the absorption of food, nutrient and vitamin. •  It should be non-irritant to stomach, intestine and should not cause diarrhea. •  It should be non-toxic, and palatable. •  It should be cheap and available.

  16. Criteria for antacid products • In order for a product to be labeled an antacid according to FDA Antacid Panel it must consist of one or more approved (active) ingredients. • Each active ingredient must contribute at least 25% of the total acid-neutralizing capacity of the product. •  The finished product must contain at least 5mEq/dose unit of acid-neutralizing capacity and raise the pH of gastric secretions to 3.5 or greater within 15 minutes. •  No more than four active antacid ingredients can be combined in any one product

  17. Classification of Antacids • Antacids are commonly classified in two groups: • Systemic Antacids & Nonsystemic antacids • Systemic Antacids: • Antacids(water soluble) which are absorbed in the systemic circulation (usually from the gut) and may cause metabolic alkalosis are called systemic antacids. • Common systemic antacids are: Sodium Bicarbonate, Sodium citrate, Sodium acetate, and Potassium citrate

  18. On systemic Antacids: • Antacids which are not absorbed from the gut and does not interrupt acid base balance (metabolic alkalosis) are called nonsystemic antacids. • Non systemic antacids are divided into-Buffer antacid & Non-buffer antacid. • Buffer antacid:They limit the rise in pH of the gastric contents to below neutrality. • e.g. Aluminum Hydroxide Gel [Al(OH)3], Magnesium hydroxide [Mg(OH)2], Magnesium Trisilicate [2MgO.3SiO2.xH2O] • Non-buffer antacid:They potentially permit the elevation in pH even above neutrality. • e.g. Calcium carbonate [CaCO3], Calcium phosphate [Ca3(PO4)2], Magnesium oxide [MgO], Magnesium Carbonate [MgCO3]

  19. Sodium bicarbonate NaHCO3 • Sodium bicarbonate USP ( Baking Soda ) • Used as antacids it can cause sharp increase in gastric pH up to 7 • HCl + NaHCO3 NaCl + H2O + CO2 • It is readily absorbed and sodium retention can result with continued use.

  20. Sodium bicarbonate USP • Usual Dose ; 300mg- 2g four times daily • May be found in many combination therapy

  21. Side effects of Sodium bicarbonate • 1- it is readily absorbed. • 2- it will inhibit the absorption of tetracyclines. • 3- increase blood pressure. • 4- Bad taste and form gases.

  22. .To overcome this problem • Combination therapy between the sodium bicarbonate + Citric acid • May form effervescent

  23. Aluminum containing antacids • Widely used, they are nonsystemic & • pH =3- 5 • Because of libration of astringent aluminum cations Al +++, they ten to be constipation • Most cause increased fecal phosphate excreation due to formation of insoluble Aluminum phosphate in the intestine tract.

  24. Types of Aluminium products • There are TWO types • 1- Aluminum hydroxide gel ( suspension) • 2- Aluminum hydroxide gel Tablets • Both gel and dry aluminum are popular antacids ( Famous) • Dose 5ml to 30 ml for suspension • 1 to 4 chewable tablets.

  25. The onset of action of the latter (Dried gel..)is slower, deepening on patient must first chew the tablet or simply suck on the tablet. • The degree of chewing will determine how finely divided will be the particles.

  26. A problem with the gels is that of a loss of antacids properties on aging .This is more of a problem with dried gel than with the liquid suspension and seems to be related to the manufacturing process. • The rate of loss of antacids action is de-pendent upon pH used to ppt the gel.

  27. The Al hydroxide gels are nonabsorbable and exert little. • If the gel is formed by ppt in a carbonate,/bicarbonate system, they may be some evolution in of CO2 ,due to reaction between HCl and HCO3-

  28. Al hydroxide gel may be adsorb pepsin and interfere with adsorption with other drugs. • May be cause constipation , nausea, vomiting,. • For long period may be cause phosphate deficiency.

  29. Calcium containing Antacids • Those used in medicine as CaCO3 are poorly absorbed salts which will only go into solution • CaCO3 Ca +2 +CO3 H2CO3 • H2O + CO2

  30. Disadvantages • Make gases • Constipation • Contraindicated in patients with renal disease. gastric hemorrhage , hypertension, dehydration of electrolytes.

  31. Magnesium containing Antacids • There are a large number of official magnesium antacids . They are porrly soluble salts & rate of dissolution is slow. • The problem is Magnesium carbonate • (MgCO3)4. Mg(OH)2.5H2O are laxatives • Dose ; 500 mg four times daily.

  32. Magnesium Hydroxide Mg(OH)2 • It is white powder, insoluble iun water,alcohol,only dissolve in dil acids • Mg(OH)2 = Mg +2 + 2OH- -- 4H2O • At high doses, magnesiumhydtoxide used as Laxative. • When used as antacid usually found as combination therapy with Al. • Dose 300-600mg

  33. Combination Therapy • Because no single antacids meets all the criteria for an ideal antacids, several combination therapy products of antacids • 1-Aluminum hydroxide gel+ Magnesium hydroxide ( Aludrox) ( Maalox ) • Found as Tablet or suspension ( Not laxative and not constipation)

  34. Maalox Tablet or Suspension

  35. Gaviscon • Alginic acid + Sodium bicarbonate mixture • Attempt to provide relife of reflux esiphagus . • The bulk tablet is chewed. • Alginic acid is hydrophilic colloidal carbohydrate obtained from sea weed. • It make foam which floate on the top pf stomach.

  36. Chewable Tablet

  37. Protective's & Adsorbents • Agent are used for treat mild diarrhea • Diarrhea is a symptom and not a disease • Diarrhea may be acute or chronic • Acute diarrhea can be caused by bacteria , toxin, chemical poisons, drugs, allergy, disease

  38. Damage or irritation to that of causing electrolytes to flow from body fluids into intestinal tract.( Short Time ) • Electrolytes should be given to the patients.

  39. Diarrhea is a serious condition, particularly for very young or elderly patients. • The loss of fluids & electrolytes can quickly lead to dehydration and electrolyte imbalances. • It is believed that some of the bacterial toxins stimulate the flow of electrolytes into the intestine.

  40. Thereby increasing the intestinal osmoticload.

  41. Chronic diarrhea • Can result from gastrointestinal surgery, carcinoma, chronic inflammation. • The chronic diarrhea for long time • The loss of electrolytes and fluids can quickly lead to dehydration and electrolytes imbalance.

  42. Drugs used for treatment • 1- Adsorbent • 2-Antispasodic agent (organic agent ) • 3-Antibacterial ( Tetracycline)

  43. 1- Adsorbents • Protective agents supposed to adsorb toxins, bacteria & viruses. • Bismuthsalts. [Bi(OH)2NO3]]4.BiO(OH). • Clays • Activated charcoal

  44. Bismuth products • Milk of Bismuth ( Bismuth cream ) • A suspension contains bismuth hydroxide and bismuth subcarbonate . • Are water insoluble, may act as mild astringent and antiseptic action.

  45. Bismuth subcarbonate • It is USP, the chemical formula is: • [(BiO)2CO3]2 .H2O • Insoluble in H2O,but soluble in acids. • It is protective agent.

  46. clays • Kaolin is a native hydrate aluminum silicate • It is found in earth as clay, some times added to pectin used for children

  47. It occurs as a soft,white or fait tyellow, when mix with H2O assumes a darker color and clay odor. • It is insoluble with H2O .It is usually found together with the vegetable bcarbohydrate pectin . • It is used as adsorbent. • It is interfer with Lincomycin

  48. Activated Charcoal USP • Used as adsorbent in the treatment diarrhea • Now the drug of choice for poisoning as antidote. • Activated charcoal is recommended as a component of first aid kits. • Also, may be used as filter in gas mask. • It adsorb CO2,N2O, O2, N2, Amines,NH3,

  49. Activated Charcoal is used in filters of gas masks because of its ability to adsorb gases.

More Related