Loperamide chemical structure
Find information on thousands of medical conditions and prescription drugs.

Imodium

Loperamide, usually as hydrochloride, is a drug effective against diarrhea resulting from gastroenteritis or inflammatory bowel disease. In most countries it is available generically under brand names such as Lopex®, Imodium®, Dimor® and Pepto® Diarrhea Control. more...

Home
Diseases
Medicines
A
B
C
D
E
F
G
H
I
Ibuprofen
Idarubicin
Idebenone
IFEX
Iloprost
Imatinib mesylate
Imdur
Imipenem
Imipramine
Imiquimod
Imitrex
Imodium
Indahexal
Indapamide
Inderal
Indocin
Indometacin
Infliximab
INH
Inosine
Intal
Interferon gamma
Intralipid
Invanz
Invirase
Iontocaine
Iotrolan
Ipratropium bromide
Iproniazid
Irbesartan
Iressa
Irinotecan
Isocarboxazid
Isoflurane
Isohexal
Isoleucine
Isomonit
Isoniazid
Isoprenaline
Isordil
Isosorbide
Isosorbide dinitrate
Isosorbide mononitrate
Isotretinoin
Itraconazole
Ivermectin
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z

Mode of action

Loperamide is an opioid receptor agonist and acts on the mu opioid receptors in the myenteric plexus large intestines; it does not affect the central nervous system like other opioids.

It works by decreasing the activity of the myenteric plexus which decreases the motility of the circular and longitudinal smooth muscles of the intestinal wall. This increases the amount of time substances stay in the intestine, allowing for more water to be absorbed out of the fecal matter. Loperamide also decreases colonic mass movements and suppresses the gastrocolic reflex.

Loperamide does not cross the blood-brain barrier and has no analgesic properties or addictive potential. Tolerance in response to long-term use has not been reported.

Contraindications

Treatment should be avoided in the presence of fever or if the stool is bloody. Treatment is not recommended for patients who could suffer detrimental effects from rebound constipation. If there is a suspicion of diarrhea associated with organisms that can penetrate the intestinal walls, such as E. coli O157:H7 or salmonella, loperamide is contraindicated.

Side-effects

Side effects can include the following: drowsiness, constipation, abdominal pain or discomfort, dry mouth, fatigue, and in rare cases toxic megacolon.

Read more at Wikipedia.org


[List your site here Free!]


Drugs, pregnancy, and lactation: GI agents: part I
From OB/GYN News, 11/15/05 by Gerald G. Briggs

Gastrointestinal complaints are common in pregnancy and the postpartum period. They include conditions such as nausea and vomiting, constipation, diarrhea, heartburn, and erosive gastroesophageal reflux disease, which may be treated with the following products:

Antiemetics. Nausea and vomiting is the most frequent GI complaint in pregnancy. A wide range of oral and parenteral antiemetics is available to treat nausea and vomiting of pregnancy (NVP). All are considered low risk for developmental toxicity (growth retardation, structural defects, functional and behavioral deficits, or death). The most commonly prescribed over-the-counter agent for this condition is doxylamine (Unisom), usually combined with vitamin [B.sub.6] (pyridoxine). These two drugs were the components of Bendectin, which was removed from the market by its manufacturer in 1983, but classified by the Food and Drug Administration as safe and effective. Other common oral medications for NVP include prochlorperazine (Compazine), metoclopramide (Reglan), trimethobenzamide (Tigan), promethazine (Phenergan), and ondansetron (Zofran).

Hyperemesis gravidarum, requires intravenous antiemetics, such as droperidol (Inapsine), prochlorperazine, and ondansetron.

Laxatives. There are seven types of products that act as laxatives: saline (phosphates and magnesium hydroxide and its salts), stimulants/irritants (cascara, bisacody1, casanthranol, senna, and castor oil), bulking agents (methylcellulose, polycarbophil, and psyllium), emollient (mineral oil), fecal softeners (docusate), hyperosmotics (glycerin, lactulose), and tegaserod (Zelnorm).

With the exception of lactulose and tegaserod, these products are available over the counter. Most do not cause direct embryo/fetal toxicity. However, castor oil, which is converted to ricinoleic acid in the gut, is an irritant that may induce premature labor. Improper use of saline laxatives can cause electrolyte imbalances, and mineral oil will prevent absorption of fat-soluble vitamins.

Of the laxatives, bulking agents and fecal softeners are the best in pregnancy. Cascara sagrada and senna are excreted into breast milk and are compatible with breast-feeding, although they may cause diarrhea in a nursing infant.

Tesgaserod, a serotonin type-4 receptor agonist, is approved for women with irritable bowel syndrome whose primary bowel symptom is constipation (and for idiopathic constipation in those under age 65). Limited animal and human data suggest a low risk for embryo/fetal toxicity.

Antidiarrheal agents. The antidiarrheal agents diphenoxylate and its active metabolite, difenoxin, are meperidine-related narcotics. Available as Lomotil and Motofen when combined with atropine to prevent abuse, they present low risk in pregnancy. Although there is potential for toxicity in a nursing infant, infrequent use is probably compatible with nursing. Loperamide (Imodium) is low risk in pregnancy and lactation. Alosetron (Lotronex), a serotonin antagonist, has both antiemetic and antidiarrheal properties. It is indicated only in women with IBS whose primary symptom is severe, chronic diarrhea. Based only on animal data, it is considered low risk in pregnancy. Because severe GI toxicity has been reported in adults, it should be avoided during lactation. Bismuth subsalicylate, such as Pepto-Bismol and Kaopectate, should not be used in pregnancy or lactation since metabolism releases salicylate.

Antacids. Types to treat heartburn include calcium carbonate, magnesium hydroxide and oxide, and aluminum hydroxide and carbonate. Since systemic absorption of antacids is negligible, recommended doses are safe in pregnancy and lactation. Sodium bicarbonate should be avoided because it is absorbed systemically and could cause alkalosis.

Antisecretory agents. These agents, used for heartburn and GERD, include the histamine [H.sub.2] antagonists cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid), and ranitidine (Zantac) and the proton pump inhibitors esomeprazole (Nexium), lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), and rabeprazole (Aciphex).

Low strengths of the histamine antagonists are available over the counter, but omeprazole is the only PPI that is available without a prescription. All of these antisecretory agents are low risk in pregnancy. The histamine antagonists are also compatible with breast-feeding. In contrast, the PPIs have carcinogenic and mutagenic properties, so prolonged use during lactation should be avoided.

Misoprostol (Cytotec), another anti-secretory agent and a prostaglandin [E.sub.1] (PG[E.sub.1]) analogue, is a proven human teratogen. It should only be used in pregnancy for its off-label indications: uterine stimulation and cervical ripening.

BY GERALD G. BRIGGS, B. PHARM.

GERALD G. BRIGGS, B.PHARM., is pharmacist clinical specialist, Women's Pavilion, Miller Children's Hospital, Long Beach, Calif.; clinical professor of pharmacy, University of California, San Francisco; and adjunct professor of pharmacy, University of Southern California, Los Angeles. He is also coauthor of the reference book "Drugs in Pregnancy and Lactation."

COPYRIGHT 2005 International Medical News Group
COPYRIGHT 2005 Gale Group

Return to Imodium
Home Contact Resources Exchange Links ebay