Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Lactulose”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1975

Lactulose therapy in Shigella carrier state and acute dysentery.

Antibiotic-resistant shigella are increasingly prevalent. Lactulose, a non-absorbable disaccharide, was investigated as an alternative therapy for shigella infection on the hypothesis that the short-chain fatty acids (inhibitory to shigella) resulting from metabolism of lactulose by normal colonic flora would diminish shigella excretion. A long-term antibiotic-refractory carrier (large bowel) excreting 10(4) to 10(7)Shigella sonnei/g of feces was given two courses of lactulose (of 24 and 16 days duration). During lactulose therapy, excretion of shigella was greatly diminished (24-day course) or suppressed below detectable levels (16-day course), but returned to pretreatment levels upon discontinuation of lactulose. The volunteers who developed induced shigellosis during an efficacy test of oral Shigella flexneri 2a vaccine were randomly given oral ampicillin, lactulose, or placebo in double-blind fashion. Daily rectal cultures were taken. After 4 days of therapy, cultures were still positive in four out of four men on lactulose, three of three on placebo and none of three on ampicillin. Mean stool pH of men receiving lactulose (6.1) was significantly lower than those getting ampicillin (7.4), P < 0.01, or placebo (7.0), P < 0.05. Only in the lactulose group was mean stool pH during therapy significantly decreased compared with the level off therapy (6.1 versus 7.1), P < 0.02. Lactulose shows promise for the treatment of shigella carriers but appears ineffective in treatment of acute shigellosis.

Acute Disease↗
PubMed1979

The effect of lactulose on urea metabolism and nitrogen excretion in cirrhotic patients.

The mechanism of action of lactulose is not known, although in vitro evidence suggests that lactulose may increase ammonia utilization and decrease ammmonia production by gut flora. If these changes occur in patients, they should be reflected in altered urea metabolism and nitrogen excretion. In seven studies conducted in 6 cirrhotic patients, the effects of lactulose on the kinetics of urea metabolism and nitrogen excretion were determined. Lactulose caused a fall in urea production (-24%, P less than 0.005) that was reflected in a decrease in both urea degradation and urinary urea excretion. Likewise, lactulose caused a decrease in the total body urea pool. The fall in urinary urea was accompanied by a large (two- to threefold) increase in stool nitrogen that was of a similar magnitude of the fall in urinary urea. Although urea degradation fell after lactulose, the intestinal (extrarenal) clearance of urea did not, indicating that the fall in urea degradation was due to the observed fall in the urea pool. The results indicate that: (a) Lactulose decreases urea production by increasing the fecal output of nitrogen, a finding compatible with altered ammonia metabolism by gut flora. (b) Lactulose decreases urea degradation, although this effect is primarily the result of a fall in the urea pool and cannot be attributed to an inhibition of urea breakdown in the gut lumen.

Aged↗
PubMed1977

Comparison of lactulose and neomycin in the treatment of chronic portal-systemic encephalopathy. A double blind controlled trial.

A randomized double blind clinical comparison of neomycin and lactulose was performed in 33 cirrhotic patients with chronic portal-systemic encephalopathy (PSE) at seven cooperating hospitals. In order to maintain double blindness, sorbitol syrup was used as a control solution along with neomycin and was compared with lactulose syrup and placebo tablets in a double drug protocol. Twenty-nine patients were studied in a crossover investigation in which each received both therapeutic regimens preceded and followed by control periods. Four additional patients received one or the other agent, but did not receive both. Serial, semiquantitative assessments were made in all patients of mental status, asterixis, and the trailmaking test (TMT) and electroencephalograms (EEG) and arterial ammonia levels. Both neomycin-sorbitol and lactulose were effective in the majority of patients (83 and 90%, respectively). Each of these parameters (mental state, asterixis, TMT, EEG, and NH3) was improved significantly by neomycin-sorbitol and lactulose. The post-treatment levels for each of these measures were similar in the neomycin and lactulose-treated groups. Mean stool pH was reduced by neomycinsorbitol to 6.1 and by lactulose to 5.5. This difference was highly significant statistically. Bowel activity was similar in the two groups. Both drugs were free of toxicity. These investigations demonstrate that both lactulose and neomycin-sorbitol are effective in the treatment of chronic portal-systemic encephalopathy.

Aged↗
PubMed1978

Lactulose syrup assessed in a double-blind study of elderly constipated patients.

The laxative effects of 50% lactulose syrup and 50% glucose syrup were compared in a 12-week, double-blind study of 47 elderly constipated patients living in a nursing home. The dosage was 30 ml daily taken at bedtime; it was reduced to 15 ml if the initial dosage produced two or more bowel movements daily. The number of bowel movements during treatment in comparison to pretreatment was significantly increased in the 42 patients (19 lactulose, 23 glucose) who completed at least 8 weeks of the study. Laculose was superior to glucose in the mean number of bowel movements per day (p less than 0.02) and in the percentage of days in which at least one bowel movement occurred (p less than 0.05). Reduction in the severity of each 5 symptoms (cramping, griping, flatulence, tenesmus, bloating) was greater with lactulose. For relief of all 5 symptoms, lactulose was significantly more effective than glucose (p less than 0.04). The striking reduction in the number of fecal impactions (only 6 in the lactulose patients vs 66 in the controls) was highly significant (p less than 0.015). The lactulose patients needed fewer enemas than did the controls. No abnormal values were observed in laboratory tests.

Aged↗
PubMed1979

The lactulose hydrogen breath test as a diagnostic test for small-bowel bacterial overgrowth.

The lactulose hydrogen breath test has been evaluated as a diagnostic test for small-bowel bacterial overgrowth using the 14C-glycocholate breath test for comparison. Twenty-seven patients with suspected bacterial overgrowth and 37 control patients were studied. The lactulose test was positive in 8 out of 9 patients with Subsequently proven bacterial overgrowth, all of whom had positive 14C-glycocholate tests. However, 6 patients with ileal disease or resection had positive 14C-glycocholate tests but negative lactulose tests. subsequent bacteriological study of duodenal juice from these patients was negative. Negative results were obtained by both tests in the remaining 12 patients, none of whom were subsequently shown to have bacterial overgrowth. All 37 control subjects had negative lactulose tests. The lactulose breath test is a simple and promising diagnostic test for the detection of small-bowel bacterial overgrowth and, unlike the 14C-glycocholate test, has the advantage of being able to distinguish bacterial overgrowth from ileal disease.

Breath Tests↗
PubMed1978

Breath hydrogen concentrations after oral lactose and lactulose in tropical malabsorption and adult hypolactasia.

Thirty-six hospital in-patients in London had breath-hydrogen concentrations measured after 50 g lactose were given orally; in 23 or them serial blood glucose concentrations were also estimated. Eight had tropical malabsorption (TM), 14 were Europeans with no detectable disease (normal group) and 14 who also had no detectable disease, were from ethnic groups known to have a very high incidence of genetically determined adult hypolactasia (hl). In 21 of them breath-hydrogen concentrations were also measured after 33.5 g of lactulose were given orally. There was a good inverse correlation between breath-hydrogen production and blood-glucose rise after lactose. Correlations between the first appearance of hydrogen (T) and the area under the hydrogen curve between 0 and 120 min (A) were inversely significant both for lactose and lactulose. Mean T was earlier and mean A greater for lactose compared with lactulose. Correlation between individual values for A after lactase and after lactulose was significant. Indirect measurements of lactase are of no value in either detecting or assessing the severity of TM; that is largely due to the very high incidence of HL in individuals exposed to that disease.

Adult↗
PubMed1975

The rectal administration of lactulose.

A lactulose colonic washout (pH 4.5) was administered to six male patients with portal systemic encephalopathy. Estimation of blood ammonia levels and electroencephalography were performed before and after each treatment. Five patients recorded a significant fall in blood ammonia level as a result of lactulose therapy (P less than .025). In the sixth subject, an enema with buffered physiological saline, pH 4.5, induced a fall in ammonia which was not increased by subsequent lactulose solution. Improvement in the electroencephalogram was recorded in all periods where a lactulose colonic washout produced a fall in blood ammonia level.

Aged↗
PubMed1978

Neomycin-sorbitol and lactulose in the treatment of acute portal-systemic encephalopathy. A controlled, double-blind clinical trial.

In a double-blind, randomized study the efficacy of lactulose was compared with neomycin-sorbitol in 45 episodes of acute nitrogenous portal-systemic encephalopathy (PSE) induced by dietary protein, azotemia, or gastrointestinal hemorrhage. All patients had underlying cirrhosis, and at the time of randomization had encephalopathy of at least grade 2 severity and arterial ammonia concentrations greater than 150 microgram/100 ml. Two thirds of the patients in each group returned to normal mental status and more than 80% in each group showed at least one grade improvement in mental state. In addition, there was equivalent improvement in asterixis, in the performance of the Number Connection Test, in the electroencephalographic pattern, and in arterial ammonia concentration. The principal difference between the two groups was a greater reduction in stool pH after lactulose therapy than after neomycin-sorbitol therapy. One patient randomized to neomycin-sorbitol had to be withdrawn from the study because of persistent vomiting related to the administration of the medication. Otherwise there were no complications attributable to therapy in either group. These data suggest that neomycin-sorbitol and lactulose are equally effective in the treatment of acute nitrogenous portal-systemic encephalopathy.

Clinical Trials as Topic↗
PubMed1979

Absorption of lactulose from mammalian gastrointestinal tract.

1. The disaccharide lactulose (galactosyl-beta-1,4-fructose) was poorly absorbed from rat small intestine in vitro and human mouth in vivo. 2. These results confirm indirect clinical evidence of poor absorption from the intestine. 3. The presence of calcium ions, or absence of sodium ions, had no effect on lactulose absorption from buccal cavity. 4. The presence of ouabain, or absence of Na+, did not increase the absorption of lactulose from small intestine. 5. It is thought that the mode of transport, in both instances, is by passive diffusion with the concentration gradient.

Adult↗
PubMed1975

Effect of lactulose on rabbits fed on a low residue diet.

The effect of lactulose (Duphalac) was tested for four months on six rabbits on a low residue diet representative of the diet ingested by the peoples of western civilization. A control group of six rabbits simply had the low residue diet and they developed a very low fecal output, with a mean wet fecal weight measured at monthly intervals varying between 2 and 4.6 gm.; increased transit times of 48 hours and intracolonic pressures which increased over four months from a colonic motility index (CMI) of 12,261 to a CMI of 28,084 in response to neostigmine. The rabbits on diet and lactulose did not develop diarrhea but produced three times the wet fecal weight of the rabbits on diet alone, with a range of mean values from 9.4-12.4 gm.; transit times remained at 24 hours which is normal transit time for rabbits on regular laboratory diet; intracolonic pressures in response to neostigmine rose only from a CMI of 11,652 to a CMI of 14,263 during the four months on diet with lactulose.

Animals↗
PubMed1978

Effect of lactulose on ammonia production in a fecal incubation system.

An in vitro fecal incubation system was used to demonstrate how lactulose influences ammonia metabolism in the colon. Lactulose and other fermentable substrates (glucose, mannitol, and sorbitol), pH and organic acid were varied independently so that their different effects could be determined. Fermentable substrate caused a fall in ammonia concentration during the period of fermentation. Acidification to pH 5.0 or less, with hydrochloric acid or a lactic-acetic acid mixture, significantly reduced ammonia generation, but unlike fermentable substrates, did not lower the existing ammonia concentration. The lactic-acetic acid mixture did not reduce ammonia generation significantly below that found with acidification by hydrochloric acid. The effect of lactulose in reducing ammonia concentration is attributed to its role as a bacterial substrate in either increasing bacterial assimilation of ammonia or reducing deamination of nitrogenous compounds. The effect of low pH in reducing generation of ammonia appears to be part of a general reduction in bacterial metabolism.

Ammonia↗
PubMed1979

Effect of lactulose, neomycin and antacid on colonic pH recorded continuously with an implanted electrode.

Colonic pH was continuously monitored by a pH electrode implanted in the transverse colon of rats over a 24-hour period. Lactulose significantly reduced the colonic pH to 5.37 +/- .39 from a fasting value of 6.77 +/- .75. Pretreatment with neomycin or concomitant use of a nonabsorbable antacid prevented lactulose-induced reduction in the colonic pH. The clinical implication of the study is that combined use of lactulose with neomycin or high doses of non-absorbable antacids in the treatment of chronic portasystemic encephalopathy may be undesirable.

Animals↗
PubMed1976

Intestinal pH and propulsion: an explanation of diarrhoea in lactase deficiency and laxation by lactulose.

Subjects deficient in lactase may experience bloating, cramps and diarrhoea after ingesting milk, due to the unhydrolysed and poorly-absorbed lactose. The diarrhoea may result from an osmotic effect of the lactose itself or its poorly-absorbed acidic products of fermentation (Weijers, van de Kamer & others, 1961; Christopher & Bayless, 1971), possibly together with an alteration of sodium and water absorption due to the lowered colonic pH (Rousseau & Sladen, 1971). Laxation by lactulose (1-4-beta-galactosidofructose) may operate through an analogous mechanism. The drug is a synthetic dissaccharide which, in oral doses of 10-20 g, relieves chronic constipation (Wesselius-de Casparis, Braadbaart & others, 1968). It is neither hydrolysed by intestinal dissaccharidase (Dahlqvist & Gryboski, 1965) nor absorbed in the gut, but it is converted in the colon mainly to lactic and acetic acids by various bacteria including Lactobacillus acidophilus. Apart from the increased osmotic effect, the pH in the proximal colon falls markedly (Bown, Gibson & others, 1974), and larger doses may reduce stool pH. Weijers & others (1961) inferred that the acidic products formed from lactose in the colon stimulate propulsion, and K.S. Liem (Philips-Duphar) suggested to us that lactulose may relieve constipation partly by stimulation of propulsion due to the lowered pH. The experiments described below support this view.

Animals↗
PubMed1978

Acidification of rat colon with lactulose. Its effects on the healing of colonic anastomoses.

Preoperative preparation of rats with lactulose, 2.5 ml/kg of a 52.5% w/w solution, for two days resulted in increased bursting pressure and bursting wall tension of low colonic anastomoses three days postoperatively when compared with unprepared controls (85.8, viz, 36.1 mm Hg and 0.55, viz, 0.19 dynes/cm X 10(-5). After seven days, there was no appreciable difference in the rats with colonic acidification and in the controls.

Animals↗
PubMed1979

Control of endotoxinemia in liver disease by lactulose and paromomycin.

Through the use of the Limulus test research has been carried out on gram-negative endotoxin in patients with hepatic cirrhosis, chronic hepatitis, acute hepatitis, and in a control group. The positivity of this test in patients with cirrhosis and chronic hepatitis was 93.3% and in cases of acute hepatitis it was 90.9%. The effect of the combined administration of lactulose and paromomycin on endotoxin blood levels has been evaluated in a group of 9 patients with acute hepatitis, 8 with cirrhosis, 1 in hepatic coma, and 1 patient with chronic persistent hepatitis: in 18 of the 19 patients the Limulus test became negative. The results have been discussed in relation to clinical and laboratory data, and to recent data concerning the interaction between intestinal bacterial flora, endotoxin, and liver. Hypotheses have been proposed regarding the hepatocellular c-AMP mediated mechanism of endotoxin action.

Chronic Disease↗