Opioids antidiarrheals

These dm may produce withdrawal symptoms in those physically dependent on the narcotics. The patient must not have taken any opiate for the last 7 to 10 days. Naloxone may prevent die action of opioid antidiarrheals, antitussives, and analgesics. This drug is used cautiously during lactation. 

Diphenoxylate + Atropine (Lomotil, Lonox) [C V] [Opioid Antidiarrheal] Uses D Action Constipating m CTidine congener, X GI motihty Dose Adults. Initial, 5 mg PO tid—qid until controlled, then 2.5-5 mg PO bid 20 mg/d max Peds >2 y. 0.3-0.4 mg/kg/24 h (of diphenoxylate) bid-qid, 10 mg/d max Caution [C, +] Contra Obstructive jaundice, D d/t bacterial Infxn children <2 y Disp Tabs, Liq SE Drowsiness, dizziness, xCTostomia, blurred vision, urinary retention, constipation Interactions T Effects W/ CNS depressants, opioids, EtOH, T risk HTN crisis W7 MAOIs EMS Monitor for Sxs of electrolyte disturbances and hypovolemia d/t D OD May cause Szs, hypotension, and anticholinergic effects (xerostomia [dry mouth], urine retention, flushed skin) activated charcoal may be effective for OD... 

Loperamide is, therefore, the opioid antidiarrheal of first choice. The prolonged contact time for intestinal contents and mucosa may also improve absorption of fluid. With overdosage, there is a hazard of ileus. The drug is contraindicated in infants below age 2 years. 

L The answer is a. (Hardman, p 922) Lactulose is a synthetic disaccharide (galactose-fructose) that is not absorbed. In moderate doses, it acts as a laxative. In higher doses, it is capable of binding ammonia and other toxins that form in the intestine in severe liver deficiency and that are believed to cause the encephalopathy. Loperamide is an antidiarrheal opioid lorazepam is a CNS depressant loxapine is a heterocyclic antipsychotic. 

Opioids. Activation of opioid receptors in the enteric nerve plexus results in inhibition of propulsive motor activity and enhancement of segmentation activity. This antidiarrheal effect was formerly induced by application of opium tincture (paregoric) containing morphine. Because of the CNS effects (sedation, respiratory depression, physical dependence), derivatives with peripheral actions have been developed. Whereas diphenoxylate can still produce clear CNS effects, loperamide does not Lullmann, Color Atlas of Pharmacology... 

Diphenoxylate Lomotil) is a meperidine derivative used as an antidiarrheal. It exhibits no morphinelike effects at low doses, but it produces mUd opioid effects, such as sedation, euphoria, and dependence, at higher doses. Its salts are highly insoluble in water, which reduces recreational use. Preparations often include atropine. 

The dangers of dependency and addiction clearly preclude the use of such compounds as morphine, meperidine, and methadone as treatment for diarrhea. Antidiarrheal specificity therefore is of paramount importance in choosing among the synthetic opioids and their analogues (e.g., diphenoxylate and loperamide). 

The antidiarrheal activity of codeine results from two actions. First, there is a decrease in the propulsive contractile activity of the small and large intestines, which delays the forward movement of the contents of the intestines. Second, codeine causes an increase in the absorption of water from the intestinal contents. These gastrointestinal effects are mediated by specific opioid receptors in the gut (as we will see in... 

The opioids contain natural and synthetic compounds that are medicinally used as analgesic, antidiarrheal, and antitussive agents. Opioids are CNS depressants and decrease blood pres-... 

As previously noted, opioids have significant constipating effects (see Chapter 31). They increase colonic phasic segmenting activity through inhibition of presynaptic cholinergic nerves in the submucosal and myenteric plexuses and lead to increased colonic transit time and fecal water absorption. They also decrease mass colonic movements and the gastrocolic reflex. Although all opioids have antidiarrheal effects, central nervous system effects and potential for addiction limit the usefulness of most. 

Shook, J.E., Lemcke, P.K., Gehrig, C.A., Hruby, V.J., Burks, T.F. Antidiarrheal properties of supraspinal mu and delta and peripheral mu, delta and kappa opioid receptors inhibition of diarrhea without constipation, J. Pharmacol. Exp. Ther. 1989, 249, 83-90. 

Schedule V. These drugs have the lowest relative abuse potential. Drugs in this category consist primarily of low doses of opioids that are used in cough medications and antidiarrheal preparations. 

The well-known antidiarrheal effect of opioids has been therapeutically exploited for many years. Diarrhea involves both an increase in the motility of the gastrointestinal tract and a decrease in the absorption of fluid and thus a loss of electrolytes (particularly sodium) and water. 

Pharmacological studies with selective agonists have shown that opioid control of intestinal electrolyte transport is predominantly mediated by delta opioid receptors [58], while the gastrointestinal propulsion is under the control of mu receptors [59,60]. The antidiarrheal effects of NEP inhibitors, such as acetorphan, the prodrug of thiorphan, have been compared to those of an opiate agonist, loperamide, in a model of castor oil-induced diarrhea in rats. When administered peripherally, they produced a delayed onset of diarrhea with no reduction in the gastrointestinal transit [61,62], as is commonly observed with loperamide [63],... 

Narcotic analgesics (narcotic agonists) such as opioids act on the central nervous system to treat moderate and severe pain, suppress respiration and coughing by acting on the respiratory and cough centers in the medulla of the brain stem. All narcotic analgesics relieve pain. All except meperidine (Demerol) are also antitussive (cough suppression) and antidiarrheal. 

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