Loperamide is an antidiarrheal drug that acts as an opioid agonist in the gut but does not cross the blood-brain barrier. It works by inhibiting the release of acetylcholine and prostaglandins, reducing peristalsis and increasing intestinal transit time. This favors water and electrolyte absorption. Loperamide is also used to reduce anal sphincter incontinence and urgency. It is effective for treating mild to moderate diarrhea, diarrhea associated with inflammatory bowel disease, and irritable bowel syndrome with predominant diarrhea. As an opioid restricted to the gut, loperamide has no analgesic effects and no potential for addiction.

1. Mechanism of action and synthesis of
antidiarrheal drug
Md. Matiur Rahman
20121207051
Department of ACCE
BSMRSTU

2. Definition of Antidiarrheal Drugs
Antidiarrheal drugs are medicines that relieve diarrhea.
Or ,
A drug or dietary fiber forming agent that relieves the symptoms of
diarrhea. The most effective antidiarrheal drugs areopioid derivatives,
which slow intestinal motility to permit greater time for the absorption of
water and electrolytes.

3. List Of Antihiarrhoeal Drugs
1. Diasorb
2. Difenoxin Hcl/Atropine
3. Diphenoxylate Attapulgite
4. Bismuth Subsalicylate
5. Crofelemer
6. Diaraid
7. Hcl/Atropine
8. Imodium
9. Imodium Multi-Symptom Relief
10.K-Pek
11. Loperamide
12. Lomotil
13. Loperamide/Simethicone
14. Maalox Total Relief
15. Motofen
16. Mytesi
17. Neodiaral
18. Octreotide
19. Opium Paregoric
20. Opium Tincture

4. Mechanism of action
•Ampicillin is able to penetrate Gram-
positive and some Gram-negative
bacteria.
•It differs from penicillin G,only by the
presence of an amino group. That
amino group, present on both
ampicillin and amoxicillin, helps them
enter the pores of the outer membrane
of Gram-negative bacteria, such as E.
coli, Proteus mirabilis
Synthesis
Ampicillin
Mechanism & Synthesis Of Antihiarrhoeal Drugs

5. Loperamide
Trade Name: generic, Imodium ®
Drug Class: Antidiarrheal, Opioid Agonist (OTC, non-prescription)

6. Mechanism of Action:
• opioid agonist
• does not cross the blood-brain barrier, has no analgesic or addictive properties)
• inhibits the release of acetylcholine and prostaglandins, thereby reducing
peristalsis, and increasing intestinal transit time, which also favorably affects
water and electrolyte movement through the bowel.
• increases the tone of the anal sphincter, reducing incontinence and urgency.
• Indications:
• mild to moderate diarrhea
• diarrhea associated with Inflammatory Bowel Disease (IBD)
• Off label: Irritable Bowel Syndrome with predominant diarrhea (IBS-D)
Side Effects: has no analgesic effects & no potential for addiction

7. Synthesis Anti-Diarrhoeal Drug
Loperamide

8. Question?