Probiotic potential of Lacticaseibacillus rhamnosus VHProbi M15 on sucralfate-induced constipation in mice.

The main objective of this study was to investigate the potential probiotic properties of Lacticaseibacillus rhamnosus VHProbi®M15 (M15). This study examined the effects of M15 on sucralfate-induced constipation in a mouse model. The BALB/c mice were randomly divided into four groups: the normal group (NOR) was without any treatment, while the constipation (CON), phenolphthalein (PHE), and probiotic (PRO) treatment groups were fed with sucralfate until the appearance of constipation symptoms. Afterward, the NOR and CON groups were given 1 ml saline orally every day until the end of the experiment; the PHE and PRO groups were given phenolphthalein or M15 suspension in 1 ml orally, respectively. Compared with the CON group, the fecal water content and intestinal peristalsis improved in the PRO group. Here, intake of M15 effectively attenuated sucralfate-induced constipation, recuperated colonic epithelial integrity, and increased serum levels of gastrointestinal excitatory neurotransmitters (motilin, gastrin, substance P). Analysis of the intestinal microbiota of mice by 16S rRNA metagenomic revealed an increase in the relative abundance of Bacteroides and a decrease in Sclerotinia, Verrucosa and Proteus in the PRO group. Compared with the CON group, the constipation-induced intestinal microecological changes were partially recovered in the PHE and PRO groups. These results demonstrate that M15 enhanced gastrointestinal transit and alleviated in mice with sucralfate-induced constipation.

Topical sucralfate for prevention of peristomal wound reaction related to percutaneous endoscopic gastrostomy in children: A randomized controlled trial.

There are no standard protocols for peristomal skin care in children with percutaneous endoscopic gastrostomy (PEG) tubes. This clinical study aimed to evaluate the efficacy of topical sucralfate as a prophylactic intervention in the peristomal wound reaction (PWR)/infection-associated PEG insertion in children. This study was a randomized, single-blind, controlled trial recruiting child under 18 years old who submitted for PEG insertion. Patients were randomly divided to receive topical sucralfate + peristomal wound care (intervention) or peristomal wound care alone (control). In the intervention group, the participants used topical 4% sucralfate cream four times a day for 2 months. Participants were assessed using the total peristomal infection score and PWR grading system at baseline week 1, and monthly up to 5 months after the initiation of the study. Forty-four children after PEG insertion were randomly assigned to two groups. Baseline characteristics of both groups were statistically similar (p > 0.05). Friedman test demonstrated statistically significant differences in grades of PWR during the follow-up period in the control group (p = 0.01); while there was not significantly different in the intervention group (p = 0.47). This finding suggests that the intervention had a prophylaxis effect. Also, there were statistically differences in the score of erythema (p = 0.001) and exudate (p = 0.06) at the seven-time points in the control group. Topical 4% sucralfate can be considered an affordable and available prophylactic treatment for reducing the PWR/infection associated with PEG insertion in children.

Randomized controlled trial of topical mupirocin versus mupirocin with sucralfate combination in chronic skin ulcers.

OBJECTIVES: The objective of this study was to carry out a head-to-head comparison of topical sucralfate combined with mupirocin versus mupirocin alone in the treatment of chronic skin ulcers with respect to both effectiveness and safety. MATERIALS AND METHODS: A parallel-group, open-label, randomized, controlled trial (CTRI/2015/12/006443) was carried out with patients suffering from skin ulcers of Wagner grading 1 or 2 persisting for over 4 weeks. Ninety-six patients were recruited in total, and the modified intention-to-treat analysis dataset included 44 participants treated with mupirocin 2% and 46 treated with combined mupirocin 2% and sucralfate 7% ointment. Both medications were applied topically thrice daily for 6 weeks. Ulcer area assessed using millimeter graph paper and wound infection score assessed on a three-point scale were effectiveness measures. Treatment-emergent adverse reactions that were reported by patients or observed by the investigators were recorded. RESULTS: The median ulcer area was significantly reduced in the combined treatment group at the end of treatment. Clinically, 41.3% of the participants in the combined group showed complete ulcer healing at 6 weeks compared to 18.18% in the mupirocin alone group (P = 0.022). The wound infection score declined significantly from baseline by the end of 3 weeks of treatment in both the groups. The frequency of qualitative wound attributes, namely pain, discharge, and erythema, remained comparable between the groups except for discharge which disappeared completely from all remaining ulcers in the combined group but was still present in 11.36% of the participants treated with mupirocin alone (P = 0.025) at 6 weeks. Adverse events were few, all local, mild, and tolerable. CONCLUSIONS: The wound healing effect of topical sucralfate adds to the antimicrobial effect of mupirocin toward the overall improvement of chronic skin ulcers. The effect of combined topical treatment needs comparison with other topical medications and wound healing strategies.

STRESS ULCER PROPHYLAXIS AS A RISK FACTOR FOR TRACHEAL COLONIZATION AND HOSPITAL-ACQUIRED PNEUMONIA IN INTENSIVE CARE PATIENTS: IMPACT ON LATENCY TIME FOR PNEUMONIA.

Stress ulcer prophylaxis is associated with bacterial colonization of respiratory tract. The aims of our study were to determine risk factors for trachea colonization (TC), colonization of pharynx (CP) or stomach (CD) and hospital-acquired pneumonia (HAP), and divide the factors into those with high risk and low risk. The study population (ventilated intensive care unit (ICU) patients eligible to receive stress ulcer prophylaxis) was randomized to receive one of three different treatment protocols: ranitidine, sucralfate, and no stress ulcer prophylaxis (control group). Clinical data relative to pre-specified risk factors for TC or HAP were recorded, as follows: APACHE II score (second risk factor), duration of intubation or tracheotomy (third risk factor), duration of mechanical ventilation (fourth risk factor) and duration of hospitalization in the ICU (fifth risk factor). Gastric pH was recorded and microbiological data regarding stomach, pharynx and trachea were collected on the 1st, 2nd, 3rd and 5th day. Fifty-eight out of 81 patients developed HAP (including ventilator-associated pneumonia), which occurred later in patients with gastric content pH <4 or those that were tracheotomized. Stress ulcer prophylaxis was not associated with HAP; however, it was proved as a risk factor for TC. TC was detected in tracheotomized patients and was caused by gram-negative pathogens. CP was associated with TC, since the majority of patients had CP before TC. A combination of risk factors (APACHE II >18, age >65, mechanical ventilation and sedation) caused a higher incidence of HAP and lower incidence of TC. HAP was more frequent in patients staying in the ICU for >10 days and those with cardiovascular disease as the underlying disorder. Sedation and previous antibiotic therapy correlated with longer latent period (LAT), while higher values of gastric content pH were related to shorter LAT. The longest LAT was found in patients colonized with Acinetobacter spp. Risk factors that accelerated the occurrence of HAP were found to have caused previous colonization. A combination of risk factors increased the likelihood of TC and HAP, and shortened LAT between TC and HAP.

[Mechanisms and risk factors for type 1 food allergies: the role of gastric digestion]. / Mechanismen und Risikofaktoren für Typ 1 Nahrungsmittelallergien: Die Rolle der gastrischen Verdauung.

True food allergens are considered as digestion stable proteins, which are absorbed through the gastrointestinal epithelium in an intact form leading to sensitization and causing systemic symptoms. According to classifications, allergens, which are digestion-labile, cause local symptoms by their cross-reactivity towards inhalative allergens. Our recent studies revealed that digestion labile allergens can also have sensitizing capacity if gastric digestion is hindered. The increase of gastric pH via acid-suppression by proton pump inhibitors, sucralfate or antacids, interferes with protein digestion, and leads to sensitization and allergic reaction in mouse models as well as in human patients. Furthermore, the inhibition of digestion increases the risk for anaphylactic responses in sensitized individuals.Even though also other factors, such as sphingolipid metabolites, are associated with the development of food allergies, it is without any doubt that the stomach has an important gate keeping function against food allergies.

Peptic ulcer disease with related drug treatment in pregnant women and congenital abnormalities in their offspring.

Peptic ulcer disease (PUD) is a common disease which can also occur in pregnant women. However, the possible association of PUD and related drug treatments in pregnant women with the risk of structural birth defects (i.e. congenital abnormalities [CA]) in their offspring has not been estimated in controlled population-based epidemiological studies. Thus, the prevalence of PUD in pregnant women who later delivered babies (cases) with different CA and in pregnant women who delivered newborns without CA (controls) was compared in the Hungarian Case-Control Surveillance of Congenital Abnormalities. Controls were matched to cases. Of 22,843 cases with congenital abnormalities, 182 (0.80%) had mothers with reported/recorded PUD, while of 38,151 controls, 261 (0.68%) were born to mothers with reported/recorded PUD. However, PUD(?) based on maternal information and/or unspecified diagnostic criteria, and PUD(!) based on endoscopic diagnosis showed different variables of mothers and newborn infants. Thus, finally, 20 case mothers and 58 control mothers with PUD(!) and related drugs were evaluated in detail. There was no higher risk for total CA group in the offspring of mothers with PUD during pregnancy (adjusted OR with 95% CI: 0.6, 0.3-0.9). Specific CA groups in cases were also assessed versus controls, but specified CA had no higher risk in the offspring of pregnant women with PUD and related drug treatments. In conclusion, a higher rate of CA was not found in the offspring of mothers with PUD.

Effect of histamine-2-receptor antagonists versus sucralfate on stress ulcer prophylaxis in mechanically ventilated patients: a meta-analysis of 10 randomized controlled trials.

INTRODUCTION: We conducted a meta-analysis in order to investigate the effect of histamine-2-receptor antagonists (H2RA) versus sucralfate on stress ulcer prophylaxis in mechanically ventilated patients in the intensive care unit (ICU). METHODS: A systematic literature search of Medline, EMBASE, Cochrane Central Register of Controlled Trials (1966 to January 2010) was conducted using specific search terms. A review of Web of Science and a manual review of references were also performed. Eligible studies were randomized control trials (RCTs) that compared H2RA and sucralfate for the prevention of stress ulcer in mechanically ventilated patients. Main outcome measures were rates of overt bleeding, clinically important gastrointestinal (GI) bleeding, ventilator-associated pneumonia, gastric colonization and ICU mortality. RESULTS: Ten RCTs with 2,092 participants on mechanical ventilation were identified. Meta-analysis showed there was a trend toward decreased overt bleeding when H2RA was compared with sucralfate (OR = 0.87, 95% CI: 0.49 to 1.53). A total of 12 clinically important GI bleeding events occurred among 667 patients (1.8%) in the H2RA group compared with 26 events among 673 patients (3.9%) in the sucralfate groups. Prophylaxis with sucralfate decreased the incidence of gastric colonization (OR = 2.03, 95% CI: 1.29 to 3.19) and ventilator-associated pneumonia (OR = 1.32, 95% CI: 1.07 to 1.64). Subgroup analysis showed H2RA was not superior to sucralfate in reducing early-onset pneumonia (OR = 0.62, 95%CI: 0.36 to 1.07) but had a higher late-onset pneumonia rate (OR = 4.36, 95%CI: 2.09 to 9.09) relative to sucralfate. No statistically significant reduction was observed in mortality of ICU between groups (OR = 1.08, 95% CI: 0.86 to 1.34). CONCLUSIONS: In patients with mechanical ventilation, H2RA resulted in no differential effectiveness in treating overt bleeding, but had higher rates of gastric colonization and ventilator-associated pneumonia. Additional RCTs of stress ulcer prophylaxis with H2RA and sucralfate are needed to establish the net benefit and risks of adverse effect in mechanically ventilated patients.

Acute vomiting in cats: rational treatment selection.

PRACTICAL RELEVANCE: The control of nausea and vomiting in cats is important in order to prevent the development of food aversion, anorexia (with its associated complications of weight loss and dehydration), and hepatic lipidosis. CLINICAL CHALLENGES: There are several antiemetic drugs that are clinically effective in cats. Making a rational choice from the available options requires knowledge of the likely cause of the vomiting, and the mechanisms of action and side effects of each drug. For example, a drug such as prochlorperazine, which can cause sedation, may be a useful first-line choice in a hospitalized cat that requires mild sedation to be handled, but would be undesirable in a critically ill cat. AUDIENCE: For companion animal and feline practitioners, the vomiting cat is a common presentation. EVIDENCE BASE: The guidance provided in this review draws on the findings of clinical trials in humans, experimental studies in cats, some clinical trials in cats, and clinical experience.

Aluminium per se and in the anti-acid drug sucralfate promotes sensitization via the oral route.

BACKGROUND: Aluminium (ALUM) is used as experimental and clinical adjuvant for parenteral vaccine formulation. It is also contained in anti-acid drugs like sucralfate (SUC). These anti-acids have been shown to cause sensitization to food proteins via elevation of the gastric pH. The aim of this study was to assess the oral adjuvant properties of ALUM, alone or contained in SUC, in a BALB/c mouse model. METHODS: Mice were fed SUC plus ovalbumin (OVA) and compared with groups where ALUM or proton pump inhibitors (PPI) were applied as adjuvants. The humoral and cellular immune responses were assessed on antigen-specific antibody and cytokine levels. The in vivo relevance was investigated in skin tests. RESULTS: The highest OVA-specific immunoglobulin G1 (IgG1) and IgE antibody levels were found in mice fed with OVA/SUC, followed by OVA/ALUM-treated animals, indicating a T helper 2 (Th2) shift in both groups. Antibody levels in other groups revealed lower (OVA/PPI-group) or baseline levels (control groups). Positive skin tests confirmed an allergic response in anti-acid or adjuvant-treated animals. CONCLUSIONS: Our data show for the first time that ALUM acts as a Th2-adjuvant via the oral route. This suggests that orally applied SUC leads to an enhanced risk for food allergy, not only by inhibiting peptic digestion but also by acting as a Th2-adjuvant by its ALUM content.

Altered intestinal absorption of L-thyroxine caused by coffee.

OBJECTIVE: To report eight case histories, and in vivo and in vitro studies showing coffee's potential to impair thyroxine (T4) intestinal absorption. DESIGN: Of eight women with inappropriately high or nonsuppressed thyroid-stimulating hormone (TSH) when T4 was swallowed with coffee/espresso, six consented to the evaluation of their T4 intestinal absorption. This in vivo test was also administered to nine volunteers. In three separate tests, two 100 microg T4 tablets were swallowed with coffee, water, or water followed, 60 minutes later, by coffee. Serum T4 was assayed over the 4-hour period of the test. Two patients and two volunteers also agreed on having tested the intestinal absorption of T4 swallowed with solubilized dietary fibers. In the in vitro studies, classical recovery tests on known concentrations of T4 were performed in the presence of saline, coffee, or known T4 sequestrants (dietary fibers, aluminium hydroxide, and sucralfate). MAIN OUTCOME: For the in vivo test, average and peak incremental rise of serum T4 (AIRST4 and PIRST4), time of maximal incremental rise of serum T4 (TMIRST4), and area under the curve (AUC) were determined. In patients and volunteers, the four outcome measures were similar in the water and water + coffee tests. In patients and volunteers, compared to water, coffee lowered AIRST4 (by 36% and 29%), PIRST4 (by 30% and 19%), and AUC (by 36% and 27%) and delayed TMIRST4 (by 38 and 43 minutes); bran was a superior interferer. In the in vitro studies, coffee was weaker than known T4 sequestrants. CONCLUSION: Coffee should be added to the list of interferers of T4 intestinal absorption, and T4 to the list of compounds whose absorption is affected by coffee.

[Handling of the gastroesophageal reflux disease (GERD) during pregnancy--a review]. / Management der gastroösophagealen Refluxkrankheit (GERD) in der Schwangerschaft.

Gastroesophageal reflux disease (GERD) is common during pregnancy. The pathogenesis is a decrease in lower oesophageal sphincter pressure caused by female sex hormones, especially progesterone. The most common symptom of GERD is heartburn. Nevertheless, serious reflux complications during pregnancy are rare. In contrast to non-pregnant patients, GERD during pregnancy should be managed with a step-up algorithm beginning with lifestyle modifications and dietary changes. Antacids or sucralfate are considered the first-line on-demand drug therapy. If symptoms persist, any of the histamine-2-receptor antagonists can be used. Proton pump inhibitors are reserved for women with intractable symptoms or complicated reflux disease. Usually, heartburn during pregnancy resolves soon after delivery but little is known about the late sequelae or, respectively, an influence on subsequent pregnancies. Accordingly a prospective study (longitudinal cohort analysis) is currently underway.

Review article: the management of heartburn in pregnancy.

Heartburn is a normal consequence of pregnancy. The predominant aetiology is a decrease in lower oesophageal sphincter pressure caused by female sex hormones, especially progesterone. Serious reflux complications during pregnancy are rare; hence upper endoscopy and other diagnostic tests are infrequently needed. Gastro-oesophageal reflux disease during pregnancy should be managed with a step-up algorithm beginning with lifestyle modifications and dietary changes. Antacids or sucralfate are considered the first-line drug therapy. If symptoms persist, any of the histamine2-receptor antagonists can be used. Proton pump inhibitors are reserved for women with intractable symptoms or complicated reflux disease. All but omeprazole are FDA category B drugs during pregnancy. Most drugs are excreted in breast milk. Of systemic agents, only the histamine2-receptor antagonists, with the exception of nizatidine, are safe to use during lactation.

[Pharmacobezoar in a patient operated on for pyloric stenosis]. / Farmacobezoar en un paciente intervenido de estenosis pilórica.

Bezoars are concretions made up of a variety of partially digested materials seen in several portions of the gastrointestinal tract; they may result in gastrointestinal obstruction. Bezoar types described in the scientific literature include bezoars resulting from drugs. Their development is usually associated with some predisposing risk factor. The case of a patient is described, who was admitted to the hospitals Emergency Department because of a clinical event suggesting a gastrointestinal bleeding episode. After admission, endoscopy demonstrated the presence of a bezoar whose components included a great number of Adalat Oros tablets. A review of the drugs that induced bezoar formation is made, and associated risk factors, formation mechanisms, bezoar appearance, and treatments used are all described.

Oral medication-induced esophageal injury in elderly patients.

SUMMARY: ABSTRACT Although oral medication induced esophageal injury (OMIEI), is a well-known and preventable condition, many cases are still missed, particularly in the elderly patients. OBJECTIVE To determine the frequency and outcome of oral medication-induced esophageal injury in elderly patients. METHODS Records of 390 patients aged over 65 years, with diagnoses of dysphagia, odynophagia, and noncardiac chest pain, over the period of 11 years, were selected for a retrospective review. Patients who had barium studies only, in whom endoscopy was not done or was unsuccessful, and those with incomplete data were excluded, leaving 250 patients for further review. RESULTS Diagnosis of OMIEI was made in 27% (68 of 250) patients. Fifty-one of 68 (75%) patients with OMIEI responded to conservative management, including H2 blockers, proton pump inhibitors, antacids, or sucralfate. The remaining 17 patients (25%) developed esophageal strictures requiring dilation. CONCLUSIONS A high index of clinical suspicion and low threshold for empiric treatment and diagnostic measures (endoscopy, barium swallow study), may be helpful, if indicated, for early diagnosis and prompt therapy of OMIEI.

Sucralfate versus mesalazine versus hydrocortisone in the prevention of acute radiation proctitis during conformal radiotherapy for prostate carcinoma. A randomized study.

PURPOSE: To assess whether the topical use of steroids or 5-aminosalicylic acid (5-ASA) is superior to sucralfate in preventing acute rectal toxicity during three-dimensional conformal radiotherapy (3DCRT) to 76 Gy. PATIENTS AND METHODS: Patients undergoing 3DCRT for prostate carcinoma at our institution were offered to be randomized to sucralfate 3 g in 15 ml suspension enema (Antepsin, mesalazine 4 g gel enema (Enterasyn, or hydrocortisone 100 mg foam enema (Colifoam. Randomization was blind to the treating physician but not to the patient. Sucralfate was chosen as control arm. Topical treatment had to be performed once daily, starting on day 1 of 3DCRT. Acute rectal toxicity was scored weekly according to RTOG criteria. Time to occurrence of grade 2+ acute rectal toxicity was taken as endpoint. RESULTS: The trial was opened in August 1999, and after the first 24 patients had been treated, arm 2 was discontinued because of eight patients receiving mesalazine, seven actually developed acute rectal toxicity (five patients grade 3 and two patients grade 2). Until May 2001, 134 consecutive patients were randomly assigned to sucralfate (63 patients), mesalazine (eight patients) or hydrocortisone (63 patients). The cumulative incidence of acute rectal toxicity at the end of treatment by arm is 61.9 +/- 6.1%, 87.5 +/- 11.7%, and 52.4 +/- 6.2% for arms 1, 2, and 3, respectively. The difference between the mesalazine group and the sucralfate group is highly significant (hazard ratio [HR] 2.5, 95% confidence interval [CI] 1.1-5.7; p = 0.03). At both uni- and multivariate analysis taking into account several patients and treatment covariates, the difference between hydrocortisone and sucralfate is not significant (HR 0.7, 95% CI 0.5-1.2; p = 0.2). CONCLUSION: Topical mesalazine is contraindicated during radiotherapy. Hydrocortisone enema is not superior to sucralfate in preventing acute rectal toxicity.

Evidence-based analysis: postoperative gastric bleeding: etiology and prevention.

Although the incidence of stomach hemorrhage is declining, stress-related gastric bleeding remains an important source of morbidity and mortality in cancer patients undergoing major surgical procedures to remove tumor. Prevention of stress-related bleeding is desirable; however, the optimal use of drugs to prevent gastric bleeding is unclear. Prophylaxis is recommended for surgical patients who require prolonged mechanical ventilation or have a coaguloathy. Histamine-2 receptor antagonists and sucralfate will reduce the likelihood of clinically important gastric-bleeding. Sucralfate appears to be less effective than H-2 blockers, but it is associated with fewer side effects such as nosocomial pneumonia. Preliminary studies show that proton pump inhibitors are most effective, have few side effects, but are most expensive. Intravenous proton pump inhibitors may be the drugs of choice for stress ulcer prophylaxis (SUP) in high-risk patients.

ABT-773: pharmacokinetics and interactions with ranitidine and sucralfate.

We assessed the pharmacokinetics and interaction of ABT-773 in 12 volunteers receiving ABT-773 alone or concomitantly with ranitidine or sucralfate. Data for 150 mg of ABT-773 were as follows: the maximum concentration of the drug in plasma (C(max)) was 318 ng/ml, its half-life was 5.66 h, and its area under the plasma concentration-time curve from 0 h to infinity (AUC(0- infinity )) was 1,662 ng. h/ml. Coadministration of ranitidine, reduced the C(max) (-25.7%) and AUC(0- infinity ) (-15.8%) significantly. Sucralfate had no impact on the bioavailability of ABT-773.

Interacciones medicamentosas de los antiulcerosos / Drug interactions of anti-ulcus drugs

La interacción es la alteración en el efecto de un fármaco producida por la administración de otro fármaco. Los antiulcerosos pueden presentar interacciones con otros fármacos por cuatro mecanismos: 1. Alteración de la absorción intestinal (antiácidos, sucralfato y antisecretores); 2. Unión competitiva a la citocromo P450 (anti-H2 e inhibidores de la bomba de protones); 3. Alteración del aclaramiento renal (anti-H2); 4. Inhibición de la alcohol-deshidrogenasa (anti-H2). Se revisan las interacciones de antiácidos, sucralfato, anti-H2, agente procinéticos (metoclopramida, betanecol, cisaprida), inhibidores de la bomba de protones, misoprostol y sales de bismuto. Se destaca que pantoprazol es el inhibidor de la bomba de protones que menos interacciones medicamentosas presenta. Por último se hacen unas recomendaciones para evitar la aparición de interacciones (AU)

Use of sucralfate in renal failure.

OBJECTIVE: To assess the potential for the development of aluminum toxicity in patients with renal insufficiency or chronic renal failure who are taking sucralfate. DATA SOURCES: Clinical literature accessed through MEDLINE (1966-December 1999) and International Pharmaceutical Abstracts (1970-December 1999). Key search terms included sucralfate, renal failure, renal insufficiency, and end-stage renal disease. DATA SYNTHESIS: Urinary excretion is an important route of elimination for systemically absorbed aluminum. Accumulation of aluminum in patients with impaired renal function may lead to significant toxicity. A potential source of aluminum is the antiulcer medication sucralfate. Studies and case reports evaluating the use and toxicity of sucralfate in patients with normal renal function, as well as those with renal failure or renal insufficiency, were reviewed. CONCLUSIONS: Aluminum accumulation and toxicity have been reported with the use of sucralfate in patients with compromised renal function. The risk of toxicity most likely represents a long-term complication of sucralfate use in this patient population. Toxicity may be enhanced by concurrent use of other aluminum-containing medications, such as phosphate binders or antidiarrheal preparations. These medications, in addition to sucralfate, should be avoided if possible in patients with end-stage renal disease. Patients with renal failure or renal insufficiency who are undergoing prolonged sucralfate therapy should be monitored for potential signs of aluminum toxicity.