Opioids
Loperamide
-
Loperamide is a synthetic piperidine opioid
-
It is an opiate analogue with weak anticholinergic property.
-
Because of poor water solubility little is absorbed form the intestine.
-
Entry into brain is negligible.
-
In addition to its opiate like action on motility, it also inhibits secretion.
-
It improves fecal continence by enhancing anal sphincter tone.
Mechanism of action
Codeine
-
Antidiarrheal action is primarily attributed to its peripheral action on small intestine and colon.
-
It does not have central effects , buit produce dependance.
-
It should be used only for a short period.
Diphenoxylate
-
It is an opioid chemically related to pethidine: used exclusively as constipating agent.
-
The antidiarrheal action is prominent, but because it is absorbed systemically and crosses blood brain barrier CNS effects may occur.
-
Atropine is added in a non-pharmacological dose to discourage abuse.
-
Abuse liability is rated low and overdose will produce disturbing atropinic side effects.
-
Use: Opiates are effective in the symptomatic treatment of acute diarrhea.
Administration
-
Paregoric is administered orally 2-3 times daily to dogs and cats once daily to calves and foals
-
Diphenoxylate is administered orally 2-3 times daily to dogs and cats
-
Loperamide is administered orally 1-2 times daily to dogs and cats
-
Codeine is administered orally 2-3 times daily to dogs and cats.
-
Adverse effects: bacterial overgrowth in the intestinal lumen of animals with infectious diarrhea may result from slowed intestinal transit time.
-
In cats, excitatory reactions render opiate use controversial.
-
Paregoric is a camphorated tincture of opium.
-
Diphenoxylate is a synthetic congener of mepridine.
-
Lomotil is diphenoxylate plus atropine.
|
Last modified: Wednesday, 25 April 2012, 10:30 AM