27. Antacids
Antacids do not decrease acid production;
they just neutralize the gastric acid
They raise the gastric pH
Disadvantage : If gastric pH goes above
4 it stimulates G - cells to release
gastrin which induces acid production
but this effect is short lasting.
( Not applicable in case of Peptic ulcers)
G - cell will help you to
re-establish normal gastric pH
34. Do not prescribe systemic antacids
to the patient, if he/she suffering
from Peptic ulcers
35. Mild acidity
Antacids do not decrease acid production; they just
neutralize the gastric acid
They raise the gastric pH above 7
Disadvantage : If gastric pH goes above 4 it
stimulates G - cells to release gastrin which
induces acid production but this effect is short
lasting.
39. Sodium bicarbonate
NaHCO₃
1. Large dose may cause
alkalosis
2. Produces CO2 ; Belching
3. It may cause acid rebound
4. Na+ overload ; Increases
risk of CHF and edema
Systemic Absorbable
Demerits :
40.
41. Welcome to Webseries on Pharmacology
'Knowledge is the key that unlocks all the doors’
Episode 3
42. St. Wilfred’s Institute of Pharmacy, Panvel.
DTE CODE: 3485
TOPIC : Antacids
Presented by : Mr.Vijay Ikale(Ass.Professor Pharmacology)
44. 1. These are insoluble
2. Poorly absorbable
3. Basic compounds
4. Reacts with stomach acid
to form chloride salt.
Characteristics :
Nonsystemic Non - absorbable
50. What to do now ????
Magnesium Compounds Aluminium Compounds
I am Laxative in action
I will cause you
Constipation
O bhaiiiiiii……. Maroo
Mujhe Maroo
51. Combination of Magnesium Compounds and Aluminium Compounds
Magnesium salts are laxative, while
aluminium salts are constipating BUT
combination of both will cancel out each
others effect and bowel movement least
affected.
Hence most of the time antacids given in
combination
Antagonistic effect
52. Non systemic antacids : Calcium Compound
Calcium carbonate
CaCO3
Speed…..
Potent and Rapidly
acting acid neutralizer
a. CO2 Liberation
b. HCL Secretion
Disadvantages
54. Drug interactions
1. Raise gastric pH
2. Forms insoluble
complexes
Decreases absorption of many drugs such as :
1. Tetracyclines (Antimicrobial agent)
2. Fluoroquinolones (Antimicrobial agent)
3. Ketoconazole (Antifungal)
4. Diazepam(Sedative Hypnotic)
5. H2 blockers (Antihistamines)
6. Phenytoin(Anticonvulsant)
7. Isoniazid and Ethambutol (Anti-TB)
55. Uses
Say No to antacids if you
are suffering from Peptic
ulcers
Treatment of acidity
and heartburn.
56. Open sores (Injuries) occurs when
stomach acid damages the lining of
the digestive tract
1. Burning stomach pain
2. Feeling of fullness
3. Bloating or belching
4. Heartburn
5. Nausea
6. Vomiting
Peptic ulcers
66. Cimetidine
Histamine Receptor Blockers ( H2 antagonist )
H2
X Ca++
and Phosphorylation
Deactivation of
H+ - K+ ATPase Pump (Proton
Pump)
H+
K+
• Absorption : 60-80 %
• Distribution : It can cross Placenta , Poor BBB penetration
• Metabolism : Liver ; Hepatic enzymes Cytochrome P - 450
• Excretion : Urine
• Duration of action : 24 hr
Happy
X
67. Mild : Headache, Dizziness, Dry mouth, Rashes,
Bowel upset
Long term use : Antiandrogenic Action
Gynaecomastia, Loss of libido, Impotency,
Temporary decrease in sperm count
Side effects : No major side effects
68. Cimetidine
( Imidazole ring )
Interactions
X
Cytochrome P - 450
Metabolism of many
drugs which will leads to
toxicity
1. Theophylline
2. Phenytoin
3. Carbamazepine
4. Metronidazole
Absorption of ketoconazole
due to reduced gastric acidity
Antacids decreases absorption of all H2 blockers
69. Ranitidine
( Furan ring )
Histamine Receptor Blockers ( H2 antagonist )
• 5 times more potent than
Cimetidine
• No antiandrogenic action
• No effect on male sexual function or
gynaecomastia
• Less inhibition of Hepatic enzymes
• Mild side effects
Advantages over Cimetidine
70. Famotidine
( Thiazole ring )
Histamine Receptor Blockers ( H2 antagonist )
• 5 to 8 times more potent than ranitidine
• No antiandrogenic action
• No effect on male sexual function or
gynaecomastia
• Less inhibition of Hepatic enzymes
• Mild side effects
• 70 % ; Excreted through kidney
• Used to treat ZE syndrome
Zollinger-Ellison
71. Roxatidine
(Piperidine ring)
Histamine Receptor Blockers ( H2 antagonist )
• Pharmacokinetics and Pharmacodynamics
is similar to that of ranitidine
• 2 times more potent than ranitidine and
long duration of action
• No antiandrogenic action
• No effect on male sexual function or
gynaecomastia
• Less inhibition of Hepatic enzymes
72. USES
Treatment of :
1. Duodenal ulcers (Acid reflux )
2. Gastric ulcers (Acid reflux )
3. Stress ulcers
4. Gastritis
5. Zollinger Ellison syndrome (Tumor ; secreting gastrin)
6. GERD ( Gastroesophageal reflux disease)
7. Prophylaxis of aspiration pneumonia
8. Urticaria (A skin rash triggered by a reaction to food, medicine or other irritants.)
Peptic ulcers
76. Omeprazole
(Benzimidazole ring)
Proton Pump inhibitors ( PPIs )
Below pH 5
a. Sulphenic acid
b. Sulphenamide
H+
K+
X
Parietal cell
Deactivation of
H+ - K+ ATPase Pump
(Proton Pump)
Happy
Omeprazole
(Benzimidazole ring)
77. Omeprazole
(Benzimidazole ring)
• All Proton Pump Inhibitors are administered
orally in enteric coated form to protect them
from molecular transformation in the acidic
gastric juice
• Should be taken on empty stomach because its
absorption (BA) affected by food
• Metabolism : Liver
• Excretion : Urine
Inhibition of HCL secretion within 1hr
Proton Pump inhibitors ( PPIs )
79. Adverse Effects
Mild
1. Nausea
2. Headache
3. Abdominal pain
4. Muscle and joint pain
5. Dizziness
6. No harmful effects in Pregnancy
Prolong use of Omeprazole leads to
Gynaecomastia and Erectile dysfunction
84. Prostaglandin Analogue : It is a compound having a structure
similar to that of another compound, but differing from it in respect
to a certain component
Misoprostol (
Exogenous)
Prostaglandin
(Endogenous)
86. Anticholinergics : Atropinic drugs, Pirenzepine, Oxyphenonium, Propantheline
Banned in India and USA
Invariably produced intolerable
side effects
1. Dry mouth
2. Blurry vision
3. Constipation
4. Decreased sweating
5. Decreased saliva
6. Sedation
7. Confusion
8. Hallucinations
9. Memory problems
10. Drowsiness
11. Trouble urinating
12. Delirium
87. Welcome to Webseries on Pharmacology
'Knowledge is the key that unlocks all the doors’
Episode 5
88. St. Wilfred’s Institute of Pharmacy, Panvel.
DTE CODE: 3485
TOPIC : Antacids
Presented by : Mr.Vijay Ikale(Ass.Professor Pharmacology)
89. Treatment of Peptic ulcers
Proton Pump Inhibitors
H2-Antihistamines
Prostaglandin analogue Anticholinergics
Ulcer Protectives Anti H. Pylori drugs
90. Ulcer Protectives : These are the substances which forms protective
coat on the surface of ulcers and prevents damage from acid, pepsin,
bile, H.Pylori bacteria
Hello …..it's Sucralfate Myself CBS
91. Sucralfate : Basic aluminium salt of sulfated sucrose (Prodrug)
Below pH 4 it polymerizes i.e forms cross links and transformed into gel like matrix which
forms protective coat over ulcer surface and prevents damage from acid, pepsin, bile,
H.Pylori bacteria
Description :
1. It does not neutralize acid
2. Not used now ; Due to effective action of H2 blockers and PPIs
3. Side effects : Constipation, Nausea, Dry mouth
4. Interactions : Affects absorption of Tetracycline, Fluoroquinolone, Phenytoin,
Digoxin and Cimetidine
93. Colloidal bismuth subcitrate
1. Water soluble compound
2. Below pH 5 it gets precipitated
3. Forms protective coat but does not neutralize acid
4. Mechanism of action is not clear
a. May increase PGE2 , Bicarbonate ions secretion
b.May forms coat over ulcer surface
c. May detach or inhibit H.Pylori directly
Side effects : Diarrhoea,
Headache, Dizziness
Patient acceptance is
compromised :
Blackening of tongue
95. Helicobacter pylori
Gram-negative, Helically-shaped ( Spiral ) Bacterium usually found in the stomach mucosa
The bacteria are believed to cause stomach problems when they penetrate the stomach’s mucous lining and this
makes the stomach cells more vulnerable to the harsh acids. Stomach acid and H. pylori together irritate the
stomach lining and may cause ulcers in your stomach or duodenum
The spiral shape of H. pylori allows them to penetrate your stomach lining, where they’re protected by mucus and
your body’s immune cells are not able to reach them.