Uso de loperamida en pacientes pediátricos con falla intestinal por síndrome de intestino corto / Use of loperamide in pediatric patients with intestinal failure due to short bowel syndrome

INTRODUCCIÓN: Este documento técnico se realizó en el marco de la Guía de Práctica Clínica para pacientes pediátricos con falla intestinal; la pregunta PICO fue la siguiente: P: pacientes de 0-18 años con falla intestinal por síndrome de intestino corto; I: loperamida; C: no uso de loperamida o uso de otros antidiarreicos; O: reducción del débito del estoma, eventos adversos, sobrecrecimiento bacteriano. a) Cuadro clínico: La falla intestinal es la reducción de la función intestinal por debajo del mínimo necesario para la absorción de nutrientes y/o agua y electrolitos, requiriendo suplementación intravenosa para mantener la salud y/o crecimiento. El síndrome de intestino corto (SIC) es la principal causa de falla intestinal. En pacientes pediátricos, las causas más comunes de SIC incluyen enterocolitis necrotizante, gastrosquisis, vólvulo intestinal, atresia intestinal, íleo meconial complicado y aganglionosis. La incidencia global de SIC es aproximadamente 24,5 por 100.000 nacidos vivos por año. Las consecuencias relacionadas con el SIC incluyen diarrea, enfermedad hepática asociada a falla intestinal, colelitiasis, nefropatía por oxalatos, y acidosis d-láctica. La diarrea tiende a ser el síntoma más debilitante y suele producirse por un aumento de la motilidad intestinal, hipersecreción gástrica, disminución de la reserva de sales biliares, reducción de los mecanismos de retroalimentación de hormonas intestinales, y sobrecrecimiento de bacterias en el intestino delgado. b) Tecnología sanitaria: Loperamida es un derivado de la fenilpiperidina con acción agonista de los receptores opioides µ. Ejerce su acción antidiarreica sobre los receptores opioides intestinales ralentizando el tránsito intestinal mediante la reducción de la actividad muscular circular y longitudinal. Asimismo, puede ayudar a disminuir las secreciones ácidas gástricas, biliares y pancreáticas reduciendo el volumen de líquido en la luz intestinal que debe ser absorbido. Las reacciones adversas asociadas a su uso incluyen calambres, náuseas, dispepsia, somnolencia, fatiga, cansancio, mareos, dolor de cabeza y sequedad de boca. Las dosis recomendadas en niños con SIC se estiman en 0.4-0.8 mg/kg/día, hasta un máximo de 8 mg/día. En Perú, cuenta con 37 registros sanitarios vigentes y dos registros con vigencia prorrogada provisional, como denominación comercial y genérica, en dosis de 2 mg, y en forma de tabletas, tabletas masticables y cápsulas. El precio mínimo en establecimientos farmacéuticos privados asciende a S/. 0.07 y S/. 0.20 en establecimientos de salud públicos. OBJETIVO: Describir la evidencia científica disponible sobre la eficacia y seguridad de loperamida en pacientes pediátricos con falla intestinal asociada a síndrome de intestino corto. METODOLOGÍA: La búsqueda de evidencia se desarrolló en Medline, The Cochrane Library y LILACS hasta el 29 de agosto de 2021, limitado a estudios en español o inglés. La búsqueda de guías de práctica clínica (GPC) y evaluaciones de tecnología sanitaria (ETS) se desarrolló en repositorios digitales de agencias elaboradoras de estos documentos. La calidad metodológica se valoró usando la herramienta de la Colaboración Cochrane para estudios aleatorizados y Newcastle-Ottawa para estudios no aleatorizados. RESULTADOS: Se identificó cinco estudios y cinco GPC. No se identificaron estudios en población pediátrica, por lo que se consideró como evidencia indirecta a estudios desarrollados en población adulta. No se identificaron ETS, ni evaluaciones económicas realizadas en países de América Latina. Reducción del débito del estoma: Todos los estudios reportaron una disminución del débito del estoma durante el tratamiento con loperamida, comparado con placebo o no uso de antidiarreicos. Comparado con placebo, Kristensen & Qvist observaron una reducción de 16.5% (p<0.02), Tytgat reportó una disminución desde un volumen inicial de 660 gr. hasta un volumen final de 500 gr. (p<0.001) y el estudio de King reportó una disminución desde 633 + 253 gr. hasta 464 + 116 gr. (p<0.02). Comparado con el no uso de antidiarreicos, el estudio de Stevens reportó una reducción del 45% (p<0.0001), mientras que el estudio de Rodrigues observó una reducción desde un volumen inicial de 923 + 213 gr. hasta un volumen final de 847 + 167 gr. Finalmente, un estudio no reportó diferencias estadísticamente significativas entre codeína y loperamida (524 + 200 gr. vs. 464 + 116 gr, respectivamente). Eventos adversos: Tres estudios reportaron ningún evento adverso durante la terapia con loperamida. Un estudio reportó vómitos al cuarto día de administración de loperamida en un paciente, mientras que un estudio reportó dolor durante la apertura de la ileostomía por incremento de la consistencia de las heces en un paciente. Sobrecrecimiento bacteriano: Ningún estudio incluido reportó información sobre este desenlace. Recomendaciones en GPC: Dos GPC de ESPEN recomiendan el uso de loperamida. En la GPC sobre nutrición parenteral del 2009, se considera a loperamida como uso de primera línea, mientras que en la GPC del 2016 sobre el manejo de falla intestinal aguda se incluye el uso de loperamida y codeína fosfato. La GPC de Cleveland Clinic para el manejo de pacientes con síndrome de intestino corto recomienda el uso de antidiarreicos incluyendo a loperamida sin una preferencia explícita. La GPC de la BSC sobre manejo de pacientes con intestino corto incluye a loperamida para el tratamiento de la diarrea, pudiendo emplearse ocasionalmente codeína fosfato. Evaluación de la calidad metodológica: Todos los ensayos clínicos aleatorizados tuvieron riesgo de sesgo alto en al menos una dimensión evaluada. El único estudio no aleatorizado incluido obtuvo una calificación de cinco estrellas sobre un máximo de nueve posibles en la escala de Newcastle-Ottawa. El nivel de confianza de la evidencia mediante la metodología GRADE, fue consideró muy bajo para los desenlaces de debito del estoma y eventos adversos, por tratarse de evidencia indirecta y con alto riesgo de sesgo. CONCLUSIONES: No se encontró evidencia sobre la eficacia y seguridad de loperamida en pacientes pediátricos con falla intestinal por síndrome de intestino corto. La evidencia procedente de cinco estudios en adultos muestra que loperamida redujo significativamente el débito del estoma cuando se comparó con placebo o el no uso de antidiarreicos. Sin embargo, no se hallaron diferencias cuando se empleó como referencia un comparador activo como codeína. Los eventos adversos asociados a loperamida fueron leves y relativamente poco frecuentes, con tres estudios que reportaron ningún evento adverso durante el periodo de observación. No se encontró evidencia que evalúe el sobrecrecimiento bacteriano. Los estudios incluidos tuvieron alto riesgo de sesgo e importantes limitaciones metodológicas, destacando un seguimiento corto (entre 1 y 7 días), y un reducido número de participantes (entre 6 y 22). El nivel de confianza de la evidencia fue considerado muy bajo. Las cinco GPC incluidas en el presente informe coinciden en recomendar el uso de loperamida, al igual que otros medicamentos antidiarreicos, para reducir la motilidad y pérdidas intestinales en pacientes con falla intestinal por síndrome de intestino corto.

Thallium-sensitive fluorescent assay reveals loperamide as a new inhibitor of the potassium channel Kv10.1.

BACKGROUND: Ion channels have been proposed as therapeutic targets for different types of malignancies. One of the most studied ion channels in cancer is the voltage-gated potassium channel ether-à-go-go 1 or Kv10.1. Various studies have shown that Kv10.1 expression induces the proliferation of several cancer cell lines and in vivo tumor models, while blocking or silencing inhibits proliferation. Kv10.1 is a promising target for drug discovery modulators that could be used in cancer treatment. This work aimed to screen for new Kv10.1 channel modulators using a thallium influx-based assay. METHODS: Pharmacological effects of small molecules on Kv10.1 channel activity were studied using a thallium-based fluorescent assay and patch-clamp electrophysiological recordings, both performed in HEK293 stably expressing the human Kv10.1 potassium channel. RESULTS: In thallium-sensitive fluorescent assays, we found that the small molecules loperamide and amitriptyline exert a potent inhibition on the activity of the oncogenic potassium channel Kv10.1. These results were confirmed by electrophysiological recordings, which showed that loperamide and amitriptyline decreased the amplitude of Kv10.1 currents in a dose-dependent manner. Both drugs could be promising tools for further studies. CONCLUSIONS: Thallium-sensitive fluorescent assay represents a reliable methodological tool for the primary screening of different molecules with potential activity on Kv10.1 channels or other K+ channels.

Poloxamer 188-Coated Ammonium Methacrylate Copolymer Nanocarriers Enhance Loperamide Permeability across Pgp-Expressing Epithelia.

Loperamide is a µ-opioid agonist with poor gastrointestinal absorption, mainly because of its modest aqueous solubility and being a P-glycoprotein (Pgp) efflux substrate. Nevertheless, studies associated with therapeutic effects strongly suggest that loperamide holds potential pharmacological advantages over traditional µ-opioid agonists commonly used for analgesia. Thus, in this Communication, we assessed in MDCK-hMDR1 cell lines the effects over loperamide uptake and efflux ratio, when loaded into Eudragit RS (ERS) nanocarriers coated with poloxamer 188 (P188). ERS was chosen for enhancing loperamide aqueous dispersibility and P188 as a potential negative Pgp modulator. In uptake assays, it was observed that Pgp limited the accumulation of loperamide into cells and that preincubation with P188, but not coincubation, led to increasing loperamide uptake at a similar extent of Pgp pharmacological inhibition. On the other hand, the efflux ratio displayed no alterations when Pgp was pharmacologically inhibited, whereas ERS/P188 nanocarriers effectively enhanced loperamide uptake and absorptive transepithelial transport. The latter suggests that loperamide transport across cells is significantly influenced by the presence of the unstirred water layer (UWL), which could hinder the visualization of Pgp-efflux effects during transport assays. Thus, results in this work highlight that formulating loperamide into this nanocarrier enhances its uptake and transport permeability.

Trial Evaluating Ambulatory Therapy of Travelers' Diarrhea (TrEAT TD) Study: A Randomized Controlled Trial Comparing 3 Single-Dose Antibiotic Regimens With Loperamide.

BACKGROUND: Recommended treatment for travelers' diarrhea includes the combination of an antibiotic, usually a fluoroquinolone or azithromycin, and loperamide for rapid resolution of symptoms. However, adverse events, postdose nausea with high-dose azithromycin, effectiveness of single-dose rifaximin, and emerging resistance to front-line agents are evidence gaps underlying current recommendations. METHODS: A randomized, double-blind trial was conducted in 4 countries (Afghanistan, Djibouti, Kenya, and Honduras) between September 2012 and July 2015. US and UK service members with acute watery diarrhea were randomized and received single-dose azithromycin (500 mg; 106 persons), levofloxacin (500 mg; 111 persons), or rifaximin (1650 mg; 107 persons), in combination with loperamide (labeled dosing). The efficacy outcomes included clinical cure at 24 hours and time to last unformed stool. RESULTS: Clinical cure at 24 hours occurred in 81.4%, 78.3%, and 74.8% of the levofloxacin, azithromycin, and rifaximin arms, respectively. Compared with levofloxacin, azithromycin was not inferior (P = .01). Noninferiority could not be shown with rifaximin (P = .07). At 48 and 72 hours, efficacy among regimens was equivalent (approximately 91% at 48 and 96% at 72 hours). The median time to last unformed stool did not differ between treatment arms (azithromycin, 3.8 hours; levofloxacin, 6.4 hours; rifaximin, 5.6 hours). Treatment failures were uncommon (3.8%, 4.4%, and 1.9% in azithromycin, levofloxacin, and rifaximin arms, respectively) (P = .55). There were no differences between treatment arms with postdose nausea, vomiting, or other adverse events. CONCLUSIONS: Single-dose azithromycin, levofloxacin, and rifaximin with loperamide were comparable for treatment of acute watery diarrhea. CLINICAL TRIAL REGISTRATION: NCT01618591.

Is it worth adding loperamide to antibiotic treatment of traveler’s diarrhea? / ¿Vale la pena agregar loperamida al tratamiento antibiótico de la diarrea del viajero?

Travelers' diarrhea is a frequent condition, especially in those traveling to high-risk areas. Although antibiotic treatment reduces the duration of diarrhea, it has been suggested adding loperamide could further reduce the symptoms. To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We identified two systematic reviews including 28 studies overall, of which 15 were randomized trials relevant for the question of interest. We extracted data from the systematic reviews, reanalysed data of primary studies and generated a summary of findings table using the GRADE approach. We concluded adding loperamide to antibiotic treatment might accelerate resolution of symptoms in traveler’s diarrhea with minimal or no adverse effects.

La diarrea del viajero es una patología frecuente, en especial en quienes se dirigen a regiones de alto riesgo. Si bien el tratamiento antibiótico reduce la duración del cuadro, se ha planteado que la asociación de loperamida podría reducir aún más los síntomas. Para responder esta pregunta utilizamos Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante búsquedas en múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Identificamos dos revisiones sistemáticas que en conjunto incluyen 28 estudios primarios, de los cuales 15 corresponden a ensayos aleatorizados. Extrajimos los datos desde las revisiones identificadas y preparamos tablas de resumen de los resultados utilizando el método GRADE. Concluimos que agregar loperamida al tratamiento con antibióticos podría acelerar la resolución del cuadro, sin asociarse probablemente a efectos adversos importantes.

Interference with P-glycoprotein improves ivermectin activity against adult resistant nematodes in sheep.

The in vivo co-administration of ivermectin (IVM) with P-glycoprotein (P-gp) modulator agents has been shown to enhance its systemic availability. However, there is no sufficient evidence on the impact that this type of drug-drug interaction may have on the in vivo efficacy against resistant nematodes in ruminant species. The current work reports on the effects of loperamide (LPM), a P-gp modulating agent, on both IVM kinetic behaviour and anthelmintic activity in infected lambs. Eighteen (18) lambs naturally infected with IVM-resistant gastrointestinal nematodes were allocated into three (3) experimental groups. Group A remained as untreated control. Animals in Groups B and C received IVM (200mug/kg, subcutaneously) either alone or co-administered with LPM (0.2 mg/kg, twice every 12h), respectively. Individual faecal samples were collected from experimental animals at days -1 and 14 post-treatment to perform the faecal eggs count reduction test (FECRT). Blood samples were collected between 0 and 14 days post-treatment and IVM plasma concentrations were determined by HPLC. Additionally, at day 14 post-treatment, lambs from all experimental groups were sacrificed and adult gastrointestinal nematode counts were performed. FECRT values increased from 78.6 (IVM alone) to 96% (IVM+LPM). Haemonchus contortus was highly resistant to IVM. The IVM alone treatment was completely ineffective (0% efficacy) against adult H. contortus. This efficacy value increased up to 72.5% in the presence of LPM. The efficacy against Trichostrongylus colubriformis increased from 77.9% (IVM alone) to 96.3% (IVM+LPM). The described favorable tendency towards improved anthelmintic efficacy was in agreement with the enhanced IVM plasma availability (P<0.05) and prolonged elimination half-life (P<0.05) induced by LPM in infected lambs. A LPM-induced P-gp modulation increases IVM systemic exposure in the host but also it may reduce P-gp efflux transport over-expressed in target resistant nematodes.

Cattle nematodes resistant to macrocyclic lactones: comparative effects of P-glycoprotein modulation on the efficacy and disposition kinetics of ivermectin and moxidectin.

The role of the drug efflux pump, known as P-glycoprotein, in the pharmacokinetic disposition (host) and resistance mechanisms (target parasites) of the macrocyclic lactone (ML) antiparasitic compounds has been demonstrated. To achieve a deeper comprehension on the relationship between their pharmacokinetic and pharmacodynamic behaviors, the aim of the current work was to assess the comparative effect of loperamide, a well-established P-glycoprotein modulator, on the ivermectin and moxidectin disposition kinetics and efficacy against resistant nematodes in cattle. Fifty (50) Aberdeen Angus male calves were divided into five (5) experimental groups. Group A remained as an untreated control. Animals in the other experimental Groups received ivermectin (Group B) and moxidectin (Group C) (200 microg/kg, subcutaneously) given alone or co-administered with loperamide (0.4 mg/kg, three times every 24 h) (Groups D and E). Blood samples were collected over 30 days post-treatment and drug plasma concentrations were measured by HPLC with fluorescence detection. Estimation of the anthelmintic efficacy for the different drug treatments was performed by the faecal egg count reduction test (FECRT). Nematode larvae were identified by pooled faecal cultures for each experimental group. Cooperia spp. and Ostertagia spp. were the largely predominant nematode larvae in pre-treatment cultures. A low nematodicidal efficacy (measured by the FECRT) was observed for both ivermectin (23%) and moxidectin (69%) in cattle, which agrees with a high degree of resistance to both molecules. Cooperia spp. was the most abundant nematode species recovered after the different drug treatments. The egg output reduction values increased from 23% to 50% (ivermectin) and from 69% to 87% (moxidectin) following their co-administration with loperamide. Enhanced systemic concentrations and an altered disposition of both ML in cattle, which correlates with a tendency to increased anthelmintic efficacy, were observed in the presence of loperamide. Overall, the in vivo modulation of P-glycoprotein activity modified the kinetic behavior and improved the efficacy of the ML against resistant nematodes in cattle. The work provides further evidence on the high degree of resistance to ML in cattle nematodes and, shows for the first time under field conditions, that modulation of P-glycoprotein may be a valid pharmacological approach to improve the activity and extend the lifespan of these antiparasitic molecules.

Loperamide plus azithromycin more effectively treats travelers' diarrhea in Mexico than azithromycin alone.

BACKGROUND: Because the combination of loperamide and some antimicrobials has proven to be more efficacious than the antimicrobial agent alone in the treatment of travelers' diarrhea, we set out to prove loperamide plus azithromycin was more efficacious than azithromycin alone. METHODS: During the summers of 2002 to 2003, 176 US adults recently arrived in Guadalajara, Mexico were enrolled in a prospective, double-blinded, randomized trial of the treatment of acute diarrhea. Subjects received single doses (1,000 or 500 mg) of azithromycin or a single 500 mg dose of azithromycin plus loperamide. Subjects gave a pre- and post-treatment stool sample for analysis and maintained daily diaries of symptoms and passage of stools. RESULTS: The duration of diarrhea was significantly (p=0.0002) shorter following treatment with azithromycin plus loperamide (11 h) than with either dose of azithromycin alone (34 h). In the first 24 hours, the average number of unformed stools passed was 3.4 (azithromycin alone) and 1.2 (combination) for a significant (p<0.0001) difference of 2.2 unformed stools. This difference equated with 20% of azithromycin-treated subjects continuing to pass six or more unformed stools in the first 24 hours post-treatment compared with only 1.7% of combination-treated subjects. CONCLUSIONS: For the treatment of travelers' diarrhea in an Escherichia coli predominant region of the world, a single 500 mg dose of azithromycin appeared as effective as a 1,000 mg dose. Loperamide plus 500 mg of azithromycin was safe and more effective than either dose of azithromycin. To realize the substantial clinical benefit that accrues to a subset of subjects, we feel loperamide should routinely be used in combination with an antimicrobial agent to treat travelers' diarrhea.

A multinational comparison of racecadotril and loperamide in the treatment of acute watery diarrhoea in adults.

BACKGROUND: Racecadotril (acetorphan) is an orally active, potent inhibitor of enkephalinase, which exerts an antihypersecretory effect without increasing intestinal transit time. The aim of this study was to compare the efficacy, safety and tolerability of racecadotril with those of loperamide by assessing their effects on the resolution of the signs and symptoms of diarrhoea in patients in developing countries who had acute watery diarrhoea of less than 5 days' duration. METHODS: 945 outpatients from 21 centres in 14 countries received racecadotril (100 mg) or loperamide (2 mg) three times daily in a single-blind study. Duration of diarrhoea was the primary measure of efficacy; secondary criteria were overall clinical response, occurrence and duration of abdominal pain and distension, and occurrence of other associated signs and symptoms. Occurrence of constipation and adverse events were the main safety assessments. RESULTS: Diarrhoea resolved rapidly with both racecadotril and loperamide (55.0 h in both groups), 92% of patients on racecadotril and 93% on loperamide being treatment successes. Racecadotril produced a significantly greater reduction in abdominal pain and distension than loperamide (P = 0.024 and 0.03, respectively). The duration of abdominal distension was significantly shorter with racecadotril (5.4 versus 24.4 h; P = 0.0001), and constipation was also significantly less frequent (16% versus 25%; P = 0.001). One-hundred-and-eighty patients (19%) experienced one or more adverse event during the study: 67 (14.2%) in the racecadotril group and 113 (23.9%) in the loperamide group (P = 0.001). CONCLUSIONS: Racecadotril resolved the symptoms of acute diarrhoea rapidly and effectively, and produced more rapid resolution of abdominal symptoms and less constipation than loperamide.

Loperamide-induced enhancement of moxidectin availability in cattle.

Moxidectin (MXD) is a milbemycin endectocide compound active at extremely low dosages against a wide variety of nematode and arthropod parasites. Different pharmacological approaches are currently being tested to delay the bile-faecal elimination and to obtain increased systemic availability for endectocide molecules in ruminants. Loperamide (LPM) is an opioid derivative, whose main pharmacological action is to abolish intestinal propulsive peristaltic waves. The influence of LPM on the pattern of faecal excretion of MXD and on its plasma disposition following intravenous (i.v.) and subcutaneous (s.c.) administrations to cattle was evaluated in the current work. Parasite-free calves were treated with MXD given either alone at 200 microg/kg by i.v. (Experiment 1) and s.c. (Experiment 2) administrations or coadministered with LPM subcutaneously injected at 0.4 mg/kg. Blood and faecal samples were collected over a period of 20 (Experiment 1) and 40 (Experiment 2) days post-treatment. The recovered plasma and faecal samples were extracted and analysed by high-performance liquid chromatography (HPLC) using fluorescence detection. Significantly higher MXD plasma concentrations were obtained after the coadministration of MXD + LPM compared with treatments with MXD alone by both routes. The higher MXD plasma concentration profiles measured after the coadministration with LPM accounted for the significantly higher AUC values obtained following the i.v. (> 46%) and s.c. (> 38%) treatments. A reduced MXD body clearance was observed in the presence of LPM. The appearance of MXD in faeces was significantly delayed after the i.v. and s.c. coadministrations of MXD with LPM (T(1/2app)=5.87 and 10.6 h, respectively) than that observed after the treatment with MXD alone (T(1/2app)=3.48 and 5.12 h). A delayed MXD peak concentration in faeces collected from MXD + LPM-treated animals compared with those receiving MXD alone, was observed. The delayed intestinal transit time caused by LPM and a potential competition between MXD and LPM for the P-glycoprotein-mediated bile/intestinal secretion processes, may account for the enhanced MXD systemic availability measured in cattle in the current work.

Treatment of traveler's diarrhea with sulfamethoxazole and trimethoprim and loperamide.

In a randomized, double-blind, placebo-controlled trial, 227 US adults with acute diarrhea in Mexico received a single dose of sulfamethoxazole and trimethoprim (1600/320 mg) or 3 days of therapy with loperamide hydrochloride (4-mg loading dose, then 2 mg orally after each loose stool), sulfamethoxazole-trimethoprim (800/160 mg orally twice daily), or the combination of both. Subjects treated with the combination had the shortest average duration of diarrhea compared with the placebo group (1 hour vs 59 hours), took the least amount of loperamide after the loading dose (3.8 mg), and had the shortest duration of diarrhea associated with fecal leukocytes or blood-tinged stools (4.5 hours). A single dose of sulfamethoxazole-trimethoprim was also efficacious (28 vs 59 hours), but loperamide alone was significantly effective only when treatment failures were treated with antibiotics (33 vs 58 hours). The combination of sulfamethoxazole-trimethoprim plus loperamide can be highly recommended for the treatment of most patients with traveler's diarrhea.