1. Dr.Jannatul Ferdoush
Assistant Professor
Department Of Pharmacology
*

2. •
• Diarrhoea is a frequent passage of liquid feces
resulting from an imbalance between secretion
& reabsorption of fluid & eletrolites.
• Causes:
1 .Infective
2.gut motility disorder.
3.IBS & malabsorption due to disease.
4.secretory tumour of GIT-
carcinoid tumour & vipoma.

3. •
• 1.For mild to moderate diarrhoea
Maintenance of fluid and electrolyte balance .
• 2.For severe acute diarrhoea
Maintenance of fluid and electrolyte balance.
Antimotility & antispasmotic drug.
antiinfective agents.

4. •
*Oral rehydration therapy with glucose-electrolite solution to
maintain the fluid & electrolite balance is the first priority.
*Composition of Oral rehydration salt:
*Na 75mmol/l
*Cl 69mmol/l
*Glucose 75mmol/l
*K 20mmol/l
*Citrate 10mmol/l
*Advantages:
Simple,effective,cheap,readily administered therapy for a
potentially fatal condition.
Hypotonic solution, so can cause more Na and water retension.

5. •
• Antimotility drug—
opioid agonist
• Antispasmotic drug—
M-R antagonist
Direct acting muscle relaxant
• Antiinfective agent—
Erythromycin,ciprofloxacin.
• Adsorbent—
kaolin,pectin,charcoal,methylcellulose.
• Octreotides

6. •
*Opioid agonist—
loperamide
Diphenoxylate
codeine
Role in GIT motility—
tone & rythmic contraction of the intestine.
propulsive activity.
tone of the large intestine.
secretion of intestine.
All sphincter are contracted.

7. *
• Advantages:
Cannot cross the blood brain barrier, so use only
for their action on GIT.
• Disadvantages:
Constipation,abdominal cramp,drowsiness,dizziness.
Large dose Diphenoxylate produces typical opoid effect.
So small dose of Atropine is used in combination to
discourage overdose.
• Contraindication:
Acute diarrhoea in children—cross BBB—respiratory
depression.
IBS—toxic dilatation of the colon.

8. *
*M-R antagonist—
Atropine
hyoscine
propantheline
dicycloverine
Role in GIT:
Inhibit M-R in the enteric nerve plexus & on smooth
muscle.
Inhibit parasympathetic activity.
Decreases spasm of intestine.

9. *
*Direct acting muscle relaxant:
Mebeverine—derivatives of reserpine.
Role in GIT:
direct relaxation action on smooth muscle of intestine.

10. *
* Diarrhoea
• Mostly viral in origin—
No antibiotic required.
Only fluid & electrolite replacement.
• Bacterial origin---mostly campylobacter species
Rx– erythromycin or ciprofloxacin.
• Travellers diarrhoea:
E.coli common.
Rx—no antibiotic required.
Only fluid & electrolite replacement

11. *
• Octreotides :synthetic analogue of somatostatin.
• Role in GIT:
It enhances Intestinal fluid secretion.
slows GIT motility in high doses.
• Use:
after vagotomy.
AIDS .
•Disadvantages:
steatorrhoea leads to deficiency of fat soluble vitamins.
Alteration of GIT motility causes nausea,
abdominal pain,flatulence.

12. •