***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background : The enkephalins , endogenous opiate substances , act as neurotransmitters along the entire digestive tract where they elicit intestinal antisecretory activity without affecting intestinal transit time or motility . Racecadotril , through inhibition of enkephalinase , reinforces the physiological activity of endogenous enkephalins and , therefore , shows intestinal antisecretory activity . Aim : We conducted the study to determine the role of racecadotril as an adjunct to the st and ard treatment of cholera in adults . Methods : The study was a double blind , r and omised , placebo controlled clinical trial involving 110 adult male cholera patients who received either racecadotril or placebo in addition to st and ard cholera treatment .  The major outcome measures ( stool output , oral rehydration solution ( ORS ) intake , requirements for unscheduled intravenous fluid infusion , and duration of diarrhoea ) were compared between the groups . Results : Of 110 patients enrolled , 54 received racecadotril and 56 received placebo . Admission clinical characteristics were comparable between the groups . There was no significant difference in ( mean ( SD ) ) total stool output  ( racecadotril v placebo 315 ( 228 ) v 280 ( 156 ) g/kg ) , total ORS intake ( 390 ( 264 ) v 369 ( 240 ) ml/kg ) , or duration of diarrhoea ( 35 ( 15 ) v 32 ( 13 ) hours ) between the groups . Clinical success , defined as resolution of diarrhoea within 72 hours of initiation of study intervention , was similar in both groups ( racecadotril v placebo 96 % v 89 % ) . The number of patients receiving unscheduled intravenous infusions was not significantly different between the groups ( racecadotril v placebo 22 % v 14 % ) . No drug related adverse effect was noted . Conclusion : The study demonstrated that racecadotril therapy , although found to be safe , does not provide additional benefit in the treatment of severe cholera in adults We compared the relative potencies of sinorphan and retorphan , the S- and R-enantiomers of acetorphan a potent inhibitor of enkephalinase ( EC 3.4.34.11 ) , to inhibit membrane metalloendopeptidase in vivo and to protect exogenous and endogenous ANF after oral administration . In mice , sinorphan was 2 - 3 fold as potent as retorphan in inhibiting the specific in vivo binding of [3H]acetorphan to kidney enkephalinase . The same potency ratio was found for the enhancement of trichloroacetic acid-precipitated radioactivity in kidneys of mice that had received 125I-ANF , which is used as a test for the protection of the hormone against inactivation in vivo . In nine healthy human volunteers who had received a low oral dosage of sinorphan or retorphan in a double-blind , placebo-controlled , r and omized trial , sinorphan was also 2 - 3 fold more potent than retorphan in inhibiting plasma enkephalinase activity . These effects were accompanied by a related rise in plasma ANF immunoreactivity , which also reflected the difference in the effectiveness of the two compounds . Sinorphan was also more potent than retorphan in enhancing urinary cyclic GMP excretion and sodium excretion in five of these subjects . These data indicate that , in humans as in rodents , enkephalinase plays a crucial role in the inactivation of ANF , its partial inhibition in vivo being accompanied by a significant protection of the exogenous or endogenous hormone as well as by typical ANF-like responses . Thus orally administered sinorphan appears to be a promising compound for therapeutic use in cardiovascular and renal diseases in which ANF has been postulated to exert beneficial effects Permeability-glycoprotein ( P-gp ) , an efflux transporter in several organs , acts at the blood – brain barrier to protect the brain from exogenous toxins . P-gp almost completely blocks brain entry of the PET radiotracer 11C-N-desmethyl-loperamide ( 11C-dLop ) . We examined the ability of 11C-dLop to quantify P-gp function in humans after increasing doses of tariquidar , an inhibitor of P-gp . Methods : Seventeen healthy volunteers had a total of 23 PET scans with 11C-dLop at baseline and after increasing doses of tariquidar  ( 2 , 4 , and 6 mg/kg intravenously ) . A subset of subjects received PET with 15O-H2O to measure cerebral blood flow . Brain uptake of 11C-dLop  was quantified in 2 ways . Without blood data , uptake was measured as area under the time – activity curve in the brain from 10 to 30 min ( AUC10–30 ) . With arterial blood data , brain uptake was quantified with compartmental modeling to estimate the rates of entry into ( K1 ) and efflux from ( k2 ) the brain . Results : Brain uptake of radioactivity was negligible at baseline and increased only slightly ( ∼30 % ) after 2 mg of tariquidar per kilogram . In contrast , 4 and 6 mg of tariquidar per kilogram increased brain uptake 2- and 4-fold , respectively . Greater brain uptake reflected greater brain entry ( K1 ) , because efflux ( k2 ) and cerebral blood flow did not differ between tariquidar-treated and untreated subjects . In the subjects who received the highest dose of tariquidar ( and had the highest brain uptake ) , regional values of K1 correlated linearly with absolute cerebral blood flow , consistent with high single-pass extraction of 11C-dLop . AUC10–30 correlated linearly with K1 . Conclusion : P-gp function at the blood – brain barrier in humans can be quantified using PET and 11C-dLop . A simple measure of brain uptake ( AUC10–30 ) may be used as a surrogate of the fully quantified rate constant for brain entry ( K1 ) and thereby avoid arterial sampling . However , to dissect the function of P-gp itself , both brain uptake and the influx rate constant must be corrected for radiotracer delivery ( blood flow ) AIM Racecadotril is a specific enkephalinase inhibitor that exhibits intestinal antisecretory activity without affecting intestinal transit . Loperamide is an effective anti-diarrheal agent , but it usually induces constipation . This study is to compare the efficacy , safety , and tolerability of racecadotril versus loperamide in the outpatient treatment of acute diarrhea in adults . METHODS A two-center , r and omized , parallel-group , single-blind study was carried out to compare the efficacy , tolerability , and safety of racecadotril ( 100 mg thrice daily ) and loperamide ( 2.0 mg 2 twice daily ) in 62 adult patients suffering from acute diarrhea . The main efficacy criterion used was the duration of diarrhea after beginning the treatment ( in hours ) . Other signs and symptoms were also evaluated . RESULTS The clinical success rates for these anti-diarrheal treatments were 95.7 % and 92.0 % for racecadotril and loperamide respectively . Patients on racecadotril had a median duration of diarrhea of 19.5 h compared with a median of 13 h for patients on loperamide . Rapid improvement in anal burn and nausea was found for each drug . However , more patients on loperamide suffered from reactive constipation ( 29.0 % vs 12.9 % ) . Itching , another adverse event was notably higher in the racecadotril group ( 28.6 % vs 0 % ) . With regard to other adverse events , the two medications showed similar occurrence rates and similar concomitant medication usage rates . CONCLUSION Racecadotril and loperamide are rapid , equally effective treatments for acute diarrhea in adults , but loperamide treatment is associated with a higher incidence of treatment-related constipation Delayed diarrhea is the main toxicity of irinotecan at the currently recommended dose of 350 mg/m2 30-minute intravenous infusion , once every 3 weeks . This phase II , multicenter , open-label , r and omized study was primarily design ed to evaluate the effect of a 15-day Tiorfan ( racecadotril ) treatment on the incidence and severity of irinotecan-induced  delayed diarrhea .  One hundred thirty-six patients with metastatic colorectal cancer who failed to respond to a 5-fluorouracil-based treatment received 714 cycles of  irinotecan . The patients were r and omly allocated either to group A ( 68 patients ) and received Tiorfan ( 300 mg/day ) from D0 to D15 or to group B ( 68 patients ) with no prophylactic treatment .  Delayed diarrhea occurred in 197 of 355 cycles ( 55 % ) in Group A and 203 of 344 cycles ( 59 % ) in Group B. grade III-IV diarrhea was reported in 17 of 40 compliant patients ( 42 % ) in group A and 31 of 68 evaluable patients ( 45 % ) in group B. No difference was observed between the two groups for delayed diarrhea characteristics , incidence , or severity . The response rate in 99 evaluable patients was 12.1 % ( 6.4%-20.2 % ) . This study has shown that Tiorfan given prophylactically at 300 mg/day has no effect on delayed diarrhea OBJECTIVE To assess the efficacy of single dose of octreotide and compare it with another antisecretory agent racecadotril in the management of acute infective diarrhea .  METHODS A r and omized control study was done in the Department of Medicine and Infectious Disease Hospital ( Department of Preventive and Social Medicine ) of SMS Medical College and Hospital . 150 patients with moderate to severe acute diarrheal illness needing hospitalization were r and omly allotted into 3 categories of 50 patients each . The control group received only fluids and antibiotics , the racecadotril group received fluid , antibiotics and oral racecadotril at dose of 1.5 mg/kg three times a day and the octreotide group received octreotide ( 100 microgram stat ) along with fluid and antibiotics . The following end points of the study were compared , namely- frequency , quantity and consistency of stools and fluid requirement per day . RESULTS The mean ( + /- SE ) frequency of stools was significantly less ( p < 0.001 ) from day 2 onwards in the octreotide group compared to the control and racecadotril group . Diarrhea stopped in half of the patients in the octreotide group by day 3 . The consistency of stools changed significantly in the octreotide group ( p < 0.001 ) . No significant difference was seen between the racecadotril and control group ( p > 0.05 ) in terms of the frequency and consistency of stools . The mean ( + /- SE ) quantity of stools was significantly decreased in the octreotide group ( p < 0.001 ) on day 2 compared to the other two groups . The mean ( + /- SE ) quantity of fluid required was almost the same in all 3 groups on day 1 ( p > 0.05 ) but it was significantly less in the octreotide group on day 2 ( p < 0.001 ) . No significant difference was seen with respect to the fluid requirement between the control and racecadotril group ( p > 0.05 ) . CONCLUSION Patients who received single dose of octreotide fared better than those patients in control and racecadotril group in terms of frequency , quantity and consistency of stools passed . The fluid requirement was also less in octreotide group . However more trials need to be done to substantiate this finding before octreotide becomes a st and ard of therapy in acute infective diarrhea BACKGROUND AND OBJECTIVES Acute chemotherapy-induced diarrhoea may require reducing or even stopping subsequent therapy . Antidiarrhoeal drug efficiency has not been extensively studied and the effects of the new antisecretory compound acetorphan -- a potent enkephalinase inhibitor active in acute diarrhoea -- are unknown . The aim of this study was to investigate the possible effects of acetorphan on 5 FU-induced  diarrhoea in man . MATERIAL AND METHODS Fifteen patients reporting acute diarrhoea following chemotherapy were included in this study . They presented with metastatic colo-rectal cancer ( n = 14 ) or pancreatic carcinoma ( n = 1 ) and were treated , once weekly , by an 8-hour IV infusion of folinic acid 200 mg/m2 and 5 FU 1,800 to 3,000 mg/m2 . In each patient , number and consistency of stools were assessed every day during the week following chemotherapy , once without ( control period ) and once with acetorphan p.o . 300 mg/d/7d . RESULTS During the control period , 3 out of 15 patients did not have significant diarrhoea , but 2 out of 3 patients had abdominal pain which was relieved by acetorphan without appearance of constip 
    Output:
    
In six r and omized studies in out patients comparing racecadotril to loperamide , resolution of symptoms occurred with similar speed and efficacy ; however , racecadotril treatment was associated with less rebound constipation and less abdominal discomfort .
In direct comparison with Saccharomyces boulardii treatment , racecadotril exhibited similar tolerability but was more efficacious .
One study compared racecadotril to octreotide in patients with acute diarrhea requiring hospitalization , rehydration , and antibiotic treatment ;  in this cohort , octreotide was more efficacious than racecadotril .
In conclusion , in adults with acute diarrhea , racecadotril is more efficacious than placebo or S. boulardii , similarly efficacious as loperamide and , in patients with moderate to severe disease as add-on to antibiotics , less than octreotide .
The tolerability of racecadotril is similar to that of placebo or S. boulardii and better than that of loperamide , particularly with regard to risk of rebound constipation .
Taken together , these data demonstrate that racecadotril is a suitable treatment to alleviate symptoms of acute diarrhea in adults