Antacids and controlling agents

1. Antacids andAntacids and
Acid-Controlling AgentsAcid-Controlling Agents
AntacidsAntacids
HH
22 Antagonists Antagonists
Proton Pump InhibitorsProton Pump Inhibitors

2. Acid-Related PathophysiologyAcid-Related Pathophysiology
The stomach secretes:The stomach secretes:
•Hydrochloric acid (HCl)Hydrochloric acid (HCl)
•BicarbonateBicarbonate
•PepsinogenPepsinogen
•Intrinsic factorIntrinsic factor
•MucusMucus
•ProstaglandinsProstaglandins

3. Glands of the StomachGlands of the Stomach
•CardiacCardiac
•PyloricPyloric
•Gastric*Gastric*
*The gastric glands are the largest in number*The gastric glands are the largest in number

4. Cells of the Gastric GlandCells of the Gastric Gland
•ParietalParietal
•ChiefChief
•MucoidMucoid

5. Cells of the Gastric GlandCells of the Gastric Gland
Parietal CellsParietal Cells
•Produce and secrete HClProduce and secrete HCl
•Primary site of action for many acid-controller drugsPrimary site of action for many acid-controller drugs

6. Cells of the Gastric GlandCells of the Gastric Gland
Chief CellsChief Cells
•Secrete pepsinogen, a proenzymeSecrete pepsinogen, a proenzyme
•Pepsinogen becomes PEPSIN when activated by Pepsinogen becomes PEPSIN when activated by
exposure to acidexposure to acid
•Pepsin breaks down proteins (proteolytic)Pepsin breaks down proteins (proteolytic)

7. Cells of the Gastric GlandCells of the Gastric Gland
Mucoid CellsMucoid Cells
•Mucus-secreting cells (surface epithelial cells)Mucus-secreting cells (surface epithelial cells)
•Provide a protective mucous coat Provide a protective mucous coat
•Protects against self-digestion by HClProtects against self-digestion by HCl

8. Hydrochloric AcidHydrochloric Acid
•Secreted by the parietal cellsSecreted by the parietal cells
•Maintains stomach at a pH of 1 to 4Maintains stomach at a pH of 1 to 4
•Secretion stimulated by:Secretion stimulated by:
–Large, fatty mealsLarge, fatty meals
–Excessive amounts of alcoholExcessive amounts of alcohol
–Emotional stressEmotional stress

9. Acid-Related DiseasesAcid-Related Diseases
•Caused by imbalance of the three cells of Caused by imbalance of the three cells of
the gastric gland and their secretionsthe gastric gland and their secretions
•Most common:Most common:HyperacidityHyperacidity
•Most harmful:Most harmful:Peptic ulcer disease (PUD)Peptic ulcer disease (PUD)
•Lay terms for overproduction of HCl by the Lay terms for overproduction of HCl by the
parietal cells: indigestion, sour stomach, parietal cells: indigestion, sour stomach,
heartburn, acid stomachheartburn, acid stomach

10. Antacids: Mechanism of ActionAntacids: Mechanism of Action
Promote the gastric mucosal defense Promote the gastric mucosal defense
mechanismsmechanisms
•Secretion of:Secretion of:
–Mucus: Protective barrier against HClMucus: Protective barrier against HCl
–Bicarbonate: Helps buffer acidic properties of Bicarbonate: Helps buffer acidic properties of
HClHCl
–Prostaglandins: Prevent activation of proton Prostaglandins: Prevent activation of proton
pumppump

11. Antacids: Mechanism of ActionAntacids: Mechanism of Action
•Antacids DO NOT prevent the Antacids DO NOT prevent the
overproduction of acid.overproduction of acid.
•Acids DO neutralize the acid once it’s in Acids DO neutralize the acid once it’s in
the stomach.the stomach.

12. Antacids: Drug EffectsAntacids: Drug Effects
Reduction of pain associated with acid-related Reduction of pain associated with acid-related
disordersdisorders
•Raising gastric pH from 1.3 to 1.6 neutralizes 50% Raising gastric pH from 1.3 to 1.6 neutralizes 50%
of the gastric acid.of the gastric acid.
•Raising gastric pH 1 point (1.3 to 2.3) neutralizesRaising gastric pH 1 point (1.3 to 2.3) neutralizes
90% of the gastric acid.90% of the gastric acid.

13. AntacidsAntacids
•OTC formulations available as:OTC formulations available as:
Capsules and tabletsCapsules and tablets PowdersPowders
Chewable tabletsChewable tablets SuspensionsSuspensions
Effervescent granules and tabletsEffervescent granules and tablets

14. AntacidsAntacids
•Aluminum saltsAluminum salts
•Magnesium saltsMagnesium salts
•Calcium saltsCalcium salts
•Sodium bicarbonateSodium bicarbonate
Used alone or in combinationUsed alone or in combination

15. AntacidsAntacids
Aluminum SaltsAluminum Salts
•Forms: carbonate, hydroxide, phosphateForms: carbonate, hydroxide, phosphate
•Have constipating effectsHave constipating effects
•Often used with magnesium to counteract Often used with magnesium to counteract
constipationconstipation
Example: aluminum carbonate (Basaljel)Example: aluminum carbonate (Basaljel)

16. AntacidsAntacids
Magnesium SaltsMagnesium Salts
•Forms: carbonate, hydroxide, oxide, trisilicateForms: carbonate, hydroxide, oxide, trisilicate
•Commonly cause a laxative effectCommonly cause a laxative effect
•Usually used with other agents to counteract this Usually used with other agents to counteract this
effecteffect
•Dangerous when used with renal failure—the failing Dangerous when used with renal failure—the failing
kidney cannot excrete extra magnesium, resulting in kidney cannot excrete extra magnesium, resulting in
accumulationaccumulation
Examples: magnesium hydroxide (MOM); Examples: magnesium hydroxide (MOM);
combination products such as Maalox, Mylanta combination products such as Maalox, Mylanta
(aluminum and magnesium)(aluminum and magnesium)

17. AntacidsAntacids
Calcium SaltsCalcium Salts
•Forms: many, but carbonate is most commonForms: many, but carbonate is most common
•May cause constipationMay cause constipation
•Their use may result in kidney stonesTheir use may result in kidney stones
•Long duration of acid action may cause increased Long duration of acid action may cause increased
gastric acid secretion (hyperacidity rebound)gastric acid secretion (hyperacidity rebound)
•Often advertised as an extra source of dietary Often advertised as an extra source of dietary
calciumcalcium
Example: Tums (calcium carbonate)Example: Tums (calcium carbonate)

18. AntacidsAntacids
Sodium BicarbonateSodium Bicarbonate
•Highly solubleHighly soluble
•Quick onset, but short durationQuick onset, but short duration
•May cause metabolic alkalosisMay cause metabolic alkalosis
•Sodium content may cause problems in patients Sodium content may cause problems in patients
with CHF, hypertension, or renal insufficiencywith CHF, hypertension, or renal insufficiency

19. Antacids and AntiflatulentsAntacids and Antiflatulents
•Antiflatulents: used to relieve the painful Antiflatulents: used to relieve the painful
symptoms associated with gassymptoms associated with gas
•Several agents are used to bind or alter Several agents are used to bind or alter
intestinal gas, and are often added to intestinal gas, and are often added to
antacid combination products.antacid combination products.

20. Antacids and AntiflatulentsAntacids and Antiflatulents
OTC AntiflatulentsOTC Antiflatulents
•activated charcoalactivated charcoal
•simethiconesimethicone
–Alters elasticity of mucus-coated bubbles, Alters elasticity of mucus-coated bubbles,
causing them to break.causing them to break.
–Used often, but there are limited data to support Used often, but there are limited data to support
effectiveness.effectiveness.

21. Antacids: Side EffectsAntacids: Side Effects
Minimal, and depend on the compound usedMinimal, and depend on the compound used
•Aluminum and calciumAluminum and calcium
–ConstipationConstipation
•MagnesiumMagnesium
–DiarrheaDiarrhea
•Calcium carbonateCalcium carbonate
–Produces gas and belching; often combined Produces gas and belching; often combined
with simethiconewith simethicone

22. Antacids: Drug InteractionsAntacids: Drug Interactions
•ChelationChelation
–Chemical binding, or inactivation, of another drugChemical binding, or inactivation, of another drug
•Chemical inactivationChemical inactivation
–Produces insoluble complexesProduces insoluble complexes
•Result: reduced drug absorptionResult: reduced drug absorption

23. Antacids: Drug InteractionsAntacids: Drug Interactions
Increased stomach pHIncreased stomach pH
•Increased absorption of basic drugsIncreased absorption of basic drugs
•Decreased absorption of acidic drugsDecreased absorption of acidic drugs
Increased urinary pHIncreased urinary pH
•Increased excretion of acidic drugsIncreased excretion of acidic drugs
•Decreased excretion of basic drugsDecreased excretion of basic drugs

24. Antacids: Nursing ImplicationsAntacids: Nursing Implications
•Assess for allergies and preexisting Assess for allergies and preexisting
conditions that may restrict the use of conditions that may restrict the use of
antacids, such as:antacids, such as:
Fluid imbalancesFluid imbalancesRenal diseaseRenal diseaseCHFCHF
PregnancyPregnancy GI obstructionGI obstruction
•Patients with CHF or hypertension should Patients with CHF or hypertension should
use low-sodium antacids such as Riopan, use low-sodium antacids such as Riopan,
Maalox, or Mylanta II.Maalox, or Mylanta II.

25. Antacids: Nursing ImplicationsAntacids: Nursing Implications
•Use with caution with other medications due Use with caution with other medications due
to the many drug interactions.to the many drug interactions.
•Most medications should be given 1 to 2 Most medications should be given 1 to 2
hours after giving an antacid.hours after giving an antacid.
•Antacids may cause premature dissolving of Antacids may cause premature dissolving of
enteric-coated medications, resulting in enteric-coated medications, resulting in
stomach upset.stomach upset.

26. Antacids: Nursing ImplicationsAntacids: Nursing Implications
•Be sure that chewable tablets are chewed Be sure that chewable tablets are chewed
thoroughly, and liquid forms are shaken well thoroughly, and liquid forms are shaken well
before giving.before giving.
•Administer with at least 8 ounces of water to Administer with at least 8 ounces of water to
enhance absorption (except for the “rapid enhance absorption (except for the “rapid
dissolve” forms).dissolve” forms).
•Caffeine, alcohol, harsh spices, and black Caffeine, alcohol, harsh spices, and black
pepper may aggravate the underlying GI pepper may aggravate the underlying GI
condition.condition.

27. Antacids: Nursing ImplicationsAntacids: Nursing Implications
•Monitor for side effects:Monitor for side effects:
–Nausea, vomiting, abdominal pain, diarrheaNausea, vomiting, abdominal pain, diarrhea
–With calcium-containing products: constipation, With calcium-containing products: constipation,
acid reboundacid rebound
•Monitor for therapeutic response:Monitor for therapeutic response:
–Notify heath care provider if symptoms are not Notify heath care provider if symptoms are not
relieved.relieved.

28. Histamine Type 2 (HHistamine Type 2 (H
22) Antagonists) Antagonists

29. HH
22 Antagonists Antagonists
•Reduce acid secretionReduce acid secretion
•All available OTCAll available OTC
•Most popular drugs for treatment of acid-Most popular drugs for treatment of acid-
related disordersrelated disorders
cimetidine (Tagamet)cimetidine (Tagamet) famotidine (Pepcid)famotidine (Pepcid)
nizatidine (Axid)nizatidine (Axid) ranitidine (Zantac)ranitidine (Zantac)

30. HH
22 Antagonists: Antagonists:
Mechanism of ActionMechanism of Action
•Block histamine (HBlock histamine (H
22) at the receptors of acid-) at the receptors of acid-
producing parietal cellsproducing parietal cells
•Production of hydrogen ions is reduced, Production of hydrogen ions is reduced,
resulting in decreased production of HClresulting in decreased production of HCl

31. HH
22 Antagonists: Drug Effect Antagonists: Drug Effect
•Suppressed acid secretion in the stomachSuppressed acid secretion in the stomach

32. HH
22 Antagonists: Therapeutic Uses Antagonists: Therapeutic Uses
•Shown to be effective for:Shown to be effective for:
Gastric ulcerGastric ulcer Gastroesophageal reflux Gastroesophageal reflux
disease (GERD)disease (GERD)
Upper GI Upper GI Duodenal ulcer (with or Duodenal ulcer (with or
bleeding bleeding without H. pylori) without H. pylori)
•May be effective for:May be effective for:
–Stress ulcersStress ulcersPeptic esophagitisPeptic esophagitis
–Prevention and management of allergic Prevention and management of allergic
conditions, when used with Hconditions, when used with H
11 blockers blockers

33. HH
22 Antagonists: Side Effects Antagonists: Side Effects
•Overall, less than 3% incidence of side Overall, less than 3% incidence of side
effectseffects
•Cimetidine may induce impotence and Cimetidine may induce impotence and
gynecomastiagynecomastia

34. HH
2 2 Antagonists: Drug InteractionsAntagonists: Drug Interactions
•CimetidineCimetidine
–Binds with P-450 microsomal oxidase system in Binds with P-450 microsomal oxidase system in
the liver, resulting in inhibited oxidation of many the liver, resulting in inhibited oxidation of many
drugs and increased drug levelsdrugs and increased drug levels
–All HAll H
22 antagonists may inhibit the absorption of antagonists may inhibit the absorption of
drugs that require an acidic GI environment for drugs that require an acidic GI environment for
absorption.absorption.

35. HH
22 Antagonists: Drug Interactions Antagonists: Drug Interactions
•SMOKING has been shown to decrease SMOKING has been shown to decrease
the effectiveness of H the effectiveness of H
22 blockers blockers

36. HH
22 Antagonists: Nursing Implications Antagonists: Nursing Implications
•Assess for allergies and impaired renal or Assess for allergies and impaired renal or
liver function.liver function.
•Use with caution in patients who are Use with caution in patients who are
confused, disoriented, or elderly.confused, disoriented, or elderly.
•Take 1 hour before or after antacids.Take 1 hour before or after antacids.
•Ranitidine may be given intravenously; follow Ranitidine may be given intravenously; follow
administration guidelines.administration guidelines.

37. Proton Pump InhibitorsProton Pump Inhibitors

38. Proton Pump InhibitorsProton Pump Inhibitors
•The parietal cells release positive hydrogen The parietal cells release positive hydrogen
ions (protons) during HCl production.ions (protons) during HCl production.
•This process is called the “proton pump.”This process is called the “proton pump.”
•HH
22 blockers and antihistamines do not stop blockers and antihistamines do not stop
the action of this pump.the action of this pump.

39. Proton Pump Inhibitors: Proton Pump Inhibitors:
Mechanism of ActionMechanism of Action
Irreversibly bind to H+/K+ ATPase enzyme.Irreversibly bind to H+/K+ ATPase enzyme.
•This bond prevents the movement of hydrogen ions This bond prevents the movement of hydrogen ions
from the parietal cell into the stomach.from the parietal cell into the stomach.
•Result: Achlorhydria—ALL gastric acid secretion Result: Achlorhydria—ALL gastric acid secretion
is blocked.is blocked.
–In order to return to normal acid secretion, the In order to return to normal acid secretion, the
parietal cell must synthesize new H+/K+ ATPase.parietal cell must synthesize new H+/K+ ATPase.

40. Proton Pump Inhibitors: Drug EffectProton Pump Inhibitors: Drug Effect
•Total inhibition of gastric acid secretionTotal inhibition of gastric acid secretion
lansoprazole (Prevacid)lansoprazole (Prevacid)omeprazole (Prilosec)omeprazole (Prilosec)
rabeprazole (Aciphex)rabeprazole (Aciphex)pantoprazole (Protonix)pantoprazole (Protonix)
esomeprazole (Nexium)esomeprazole (Nexium)

41. Proton Pump Inhibitors: Proton Pump Inhibitors:
Therapeutic UsesTherapeutic Uses
•GERD maintenance therapyGERD maintenance therapy
•Erosive esophagitisErosive esophagitis
•Short-term treatment of active duodenal and Short-term treatment of active duodenal and
benign gastric ulcersbenign gastric ulcers
•Zollinger-Ellison syndromeZollinger-Ellison syndrome
•Treatment of H. pylori-induced ulcersTreatment of H. pylori-induced ulcers

42. Proton Pump Inhibitors: Side EffectsProton Pump Inhibitors: Side Effects
•Safe for short-term therapySafe for short-term therapy
•Incidence low and uncommonIncidence low and uncommon

43. Proton Pump Inhibitors: Proton Pump Inhibitors:
Nursing ImplicationsNursing Implications
•Assess for allergies and history of liver Assess for allergies and history of liver
diseasedisease
•Pantoprazole is the only proton pump Pantoprazole is the only proton pump
inhibitor available for parenteral inhibitor available for parenteral
administration, and can be used for patients administration, and can be used for patients
who are unable to take oral medicationswho are unable to take oral medications
•May increase serum levels of diazepam, May increase serum levels of diazepam,
phenytoin, and cause increased chance for phenytoin, and cause increased chance for
bleeding with warfarinbleeding with warfarin

44. Proton Pump Inhibitors: Proton Pump Inhibitors:
Nursing ImplicationsNursing Implications
Instruct the patient taking omeprazole:Instruct the patient taking omeprazole:
•It should be taken before meals.It should be taken before meals.
•The capsule should be swallowed whole, not The capsule should be swallowed whole, not
crushed, opened or chewed.crushed, opened or chewed.
•It may be given with antacids.It may be given with antacids.
•Emphasize that the treatment will be short-term.Emphasize that the treatment will be short-term.

45. Other DrugsOther Drugs
•sucralfate (Carafate)sucralfate (Carafate)
•misoprostol (Cytotec)misoprostol (Cytotec)

46. Sucralfate (Carafate)Sucralfate (Carafate)
•Cytoprotective agentCytoprotective agent
•Used for stress ulcers, erosions, PUDUsed for stress ulcers, erosions, PUD
•Attracted to and binds to the base of ulcers Attracted to and binds to the base of ulcers
and erosions, forming a protective barrier and erosions, forming a protective barrier
over these areasover these areas
•Protects these areas from pepsin, which Protects these areas from pepsin, which
normally breaks down proteins (making normally breaks down proteins (making
ulcers worse)ulcers worse)

47. Sucralfate (Carafate)Sucralfate (Carafate)
•Little absorption from the gutLittle absorption from the gut
•May cause constipation, nausea, and dry May cause constipation, nausea, and dry
mouthmouth
•May impair absorption of other drugs, May impair absorption of other drugs,
especially tetracyclineespecially tetracycline
•Binds with phosphate; may be used in Binds with phosphate; may be used in
chronic renal failure to reduce phosphate chronic renal failure to reduce phosphate
levelslevels
•Do not administer with other medicationsDo not administer with other medications

48. misoprostol (Cytotec)misoprostol (Cytotec)
•Synthetic prostaglandin analogueSynthetic prostaglandin analogue
•Prostaglandins have cytoprotective activity:Prostaglandins have cytoprotective activity:
–Protect gastric mucosa from injury by enhancing Protect gastric mucosa from injury by enhancing
local production of mucus or bicarbonatelocal production of mucus or bicarbonate
–Promote local cell regenerationPromote local cell regeneration
–Help to maintain mucosal blood flowHelp to maintain mucosal blood flow

49. misoprostol (Cytotec)misoprostol (Cytotec)
•Used for prevention of NSAID-induced Used for prevention of NSAID-induced
gastric ulcersgastric ulcers
•Doses that are therapeutic enough to treat Doses that are therapeutic enough to treat
duodenal ulcers often produce abdominal duodenal ulcers often produce abdominal
cramps, diarrheacramps, diarrhea