Henoch Schonlein purpura and antacids / 中国小儿急救医学

Henoch Schonlein purpura(HSP), also known as immunoglobulin A vasculitis, is the most common vasculitis in children, which involves skin, gastrointestinal tract, joints and kidney.Glucocorticoid is the conventional treatment for HSP patients with digestive system symptoms.Antacids, including H 2-receptor antagonists and proton pump inhibitors, are often used in combination with glucocorticoids in order to avoid the adverse reactions of glucocorticoids therapy.Antacids may play a role in the treatment of HSP patients by alleviating gastrointestinal symptoms, adjuvant treatment of secondary acute pancreatitis, inhibiting Helicobacter pylori and reducing the adverse reactions of glucocorticoids.However, there are few studies and more exploration is needed.

Histamine Excites Rat GABAergic Ventral Pallidum Neurons via Co-activation of H1 and H2 Receptors / 神经科学通报·英文版

The ventral pallidum (VP) is a crucial component of the limbic loop of the basal ganglia and participates in the regulation of reward, motivation, and emotion. Although the VP receives afferent inputs from the central histaminergic system, little is known about the effect of histamine on the VP and the underlying receptor mechanism. Here, we showed that histamine, a hypothalamic-derived neuromodulator, directly depolarized and excited the GABAergic VP neurons which comprise a major cell type in the VP and are responsible for encoding cues of incentive salience and reward hedonics. Both postsynaptic histamine H1 and H2 receptors were found to be expressed in the GABAergic VP neurons and co-mediate the excitatory effect of histamine. These results suggested that the central histaminergic system may actively participate in VP-mediated motivational and emotional behaviors via direct modulation of the GABAergic VP neurons. Our findings also have implications for the role of histamine and the central histaminergic system in psychiatric disorders.

Prevalencia de prescripción inapropiada de terapia supresora de ácido en adultos hospitalizados en un hospital general de Bogotá / Prevalence of Inappropriate Prescription of Acid Suppression Therapy among Adults Hospitalized at a General Hospital in Bogotá

Resumen Objetivo: determinar la prevalencia de prescripción de terapia supresora de ácido (TSA) conformada por los inhibidores de la bomba de protones (IBP) y los antagonistas de los receptores H2 (AR-H2) en pacientes adultos hospitalizados en el Hospital Universitario Fundación Santa Fe de Bogotá (HU-FSFB) que no corresponda con las indicaciones de las guías de práctica clínica (GPC). Métodos: estudio observacional descriptivo de corte transversal que incluyó pacientes adultos hospitalizados en el HU-FSFB con prescripción de TSA de novo, determinando las indicaciones de la TSA y comparándolas con las indicaciones validadas. Se excluyeron los pacientes con prescripción o consumo previo de TSA durante 2 semanas y pacientes internados en la unidad de cuidados intensivos (UCI) o con hospitalización menor de un día. Resultados: entre enero y julio de 2015 se incluyeron 306 pacientes con un promedio de edad de 56,6 (+38) años, con una prevalencia de prescripción de TSA sin indicación basada en la evidencia del 59,5%. Las indicaciones no basadas en la evidencia más comunes fueron profilaxis de sangrado por úlcera gastrointestinal en pacientes de bajo riesgo (64,9%) y causa no establecida (13,7%). Se encontró una asociación estadísticamente significativa entre el tiempo de hospitalización menor de 7 días (odds ratio [OR]: 2,39; intervalo de confianza [IC] 95%: 1,4-3,9) y edad menor de 60 años (OR: 1,9; IC 95%: 1,2-3,03) con prescripción inapropiada de TSA. Conclusión: existe una alta prevalencia (59,5%) de prescripción inapropiada de TSA en pacientes adultos hospitalizados con asociación positiva en menores de 60 años y corta hospitalización en el HU-FSFB.

Abstract Objective: This study's objective was to determine the prevalence of prescriptions of acid suppression therapy consisting of proton pump inhibitors (PPIs) or H2 receptor antagonists (H2RA) in adult patients hospitalized in the Hospital Universitario - Fundación Santa Fe de Bogotá (HU-FSFB - Santa Fe de Bogotá Foundation University Hospital) that are not in accordance with clinical practice guidelines (CPG). Methods: This is a cross-sectional descriptive observational study that included adult patients hospitalized in the HU-FSFB who were treated with acid suppressors for the first time. We determined the indications for prescriptions used and compared them with validated indications. We excluded patients who had previously taken acid suppressants for two weeks, patients admitted to the intensive care unit, and patients who stayed in the hospital for less than one day. Results: Between January and July 2015, 306 patients with an average age of 56.6 years were included in this study. The prevalence of acid suppression prescriptions without indications based on the evidence was 59.5%. The most common indications were prophylaxis of bleeding due to gastrointestinal ulcers in low risk patients (64.9%) and cause not established (13.7%). Statistically significant associations were found between inappropriate prescription of acid suppression and hospitalization times of less than seven days (OR: 2.39 95% CI 1.4-3.9) and ages of less than 60 years (OR: 1.9 95% CI 1.2-3.03). Conclusion: The prevalence of inappropriate prescriptions of acid suppression for adult patients hospitalized in the HU-FSFB was (59.5%). There were positive associations with ages under 60 years and short hospital stays.

Study on Synthetic Process of Roxatidine Acetate / 沈阳医学院学报

Objective: To synthesize roxatidine acetate and its salt. Methods: Using orthogonal test method, reactant ratio was made. Roxatidine acetate was synthesized. Excel was used to synthesize data and make statistics chart. Result: Salt of roxatidine ac?etate was synthesized in four steps with overall yield of 28?8%. Conclusion: The process is moderate and simple and the production cost is low.

A Study to Evaluate the Symptomatic Efficacy and Safety of LafaxidTM (Lafutidine 10mg) in Patients with Acid Peptic Disorders in India.

Aims: To evaluate the symptomatic efficacy and safety of Lafaxid™ (lafutidine 10 mg) in Indian patients with Acid Peptic disorder (APD). Study Design: An observational, prospective, uncontrolled, open-label multi-centric study. Place and Duration of Study: Patients were recruited from 12 cities across India by 61 investigators, between October 2010 and December 2011. Methodology: We included 1500 patients (973 men, 527 women; age range 15-85 years) with Acid Peptic disorder. Lafutidine (10 mg tablets) was prescribed by the physicians as once daily dose (OD) for 28 days. The efficacy was analysed based on the change in the symptom baseline score on the 100 point Visual Analogue Scale (VAS) for individual symptoms, and the safety was determined based on adverse events reported during the study with the prescribed usage of lafutidine on day 14 and day 28 after start of the treatment. Results: Lafutidine monotherapy was given to 1378 patients. A very high reduction in the mean VAS score was observed from baseline for individual symptoms, viz. nausea, vomiting, belching, heart burn, epigastric pain, acid regurgitation, abdominal bloating & loss of appetite at the end of the study. The global mean VAS score (a sum of individual symptom VAS score) of these patients decreased from 120.34 ± 67.58 to 14.18 ± 26.97 at the end of the study (P < .001). There were 124 APD patients, previously treated but uncontrolled, with acid inhibitors like PPIs, H2RAs etc., also showed a significant reduction (157.42 ± 83.88 to 26.47 ± 46.34) in the VAS score on day 28 (P<.001). During the entire study, adverse events of mild and moderate nature were observed in 0.4% (6 patients) of the total patient population. Conclusion: The present study demonstrates that therapy with Lafaxid™ is symptomatically effective and well tolerated in patients with APDs.

Quantitative determination of Cimetidine in both bulk and formulations using neutralization titrations.

Cimetidine is the selective H2 receptor antagonist and inhibits the secretion of hydrochloric acid in the stomach. In the present study, simple titrimetric method was developed. Respective quantities of Cimetidine were taken in aqueous methanol and acetic acid titrated against 0.1N hydrochloric acid and 0.1N perchloric acid using methyl orange and crystal violet as indicators for neutralization and non-aqueous titrations. All the titrations are carried out by running simultaneous blank determinations. The final titer values are subtracted from blank to get actual amount of acid consumed was determined. These methods were found to be sensitive and inexpensive, do not require any sample processing steps and can be utilized for estimation of cimetidine in bulk and formulations.

Two Cases of H2-Receptor Antagonist Hypersensitivity and Cross-Reactivity

H2-receptor antagonists, such as cimetidine, ranitidine and famotidine, are some of the most commonly prescribed medications for gastric acid-related disorders. These compounds are generally well-tolerated and anaphylactic reactions to them are rare. Here, we report two cases of H2-receptor antagonist-induced anaphylactic reactions: the first presented with sudden dyspnea, sneezing, urticaria, and swelling of the eyelids after ranitidine intake. The second presented with sudden severe urticaria, facial swelling, chest discomfort, dizziness, and hypotension. Possible cross-reactivity with other H2-receptor antagonists was assessed by oral challenge and skin tests. To date, only a few reports addressing cross-reactivity among H2-receptor antagonists have been published. We review the literature and summarize the data available on drug cross-reactivity in H2-receptor antagonist hypersensitivity.

Profilaxia dos sangramentos gastrintestinais em Medicina de Urgência / Prophylaxis of gastrointestinal bleeding in Emergency Medicine

JUSTIFICATIVA E OBJETIVOS: O sangramento gastrintestinal agudo é uma condição comum que, geralmente, demanda admissão em unidades de emergência, além de representar também complicação frequente naqueles pacientes previamente internados em unidades de terapia intensiva (UTI). A hemorragia digestiva alta (HDA) possui incidência anual de 50 a 150 para cada 100.000 habitantes, ocorrendo duas vezes mais em homens e aumenta com a idade; a hemorragia digestiva baixa (HDB) apresenta incidência de 20,5 a 27 para cada 100.000 habitantes e a úlcera por estresse é clinicamente evidente em 15% dos casos sem profilaxia e em 1,5% a 8% daqueles com profilaxia. Neste cenário, este estudo teve como objetivo apresentar os métodos profiláticos primários e secundários utilizados nos sangramentos gastrintestinais em Medicina de urgência, bem como suas indicações atuais baseadas em evidências. CONTEÚDO: Revisão narrativa com período delimitado entre os anos de 1970 a 2010, com busca de artigos disponíveis e resumos em bases de dados como Scielo, LILACS, Medline, Pubmed, Sumsearch, National Guideline Clearinghouse, assim como livros relacionados à área de Medicina intensiva e emergência. CONCLUSÃO: No manuseio das úlceras por estresse são utilizados os antagonistas do receptor H2 (AR2H) como método de escolha, seguidos do sucralfato, antiácidos e inibidores da bomba de prótons (IBP). Nos sangramentos gastrintestinais utilizam-se preferencialmente os IBP e nas roturas de varizes esofágicas, escleroterapia e ligaduras elásticas. Nestes casos, o ressangramento pode ser prevenido com betabloqueadores e nitrato.

BACKGROUND AND OBJECTIVES: Acute gastrointestinal bleeding is a common condition that usually requires admission to the emergency room and also represents a complication in patients previously hospitalized in intensive care units (ICU). The upper gastrointestinal bleeding (UGIB) has an annual incidence of 50-150 per 100,000 inhabitants, occurring twice as often in men and increases with age, the lower gastrointestinal bleeding presents incidence from 20.5 to 27 per 100,000 and the stress ulcer is clinically evident in 15% of cases without prophylaxis and 1.5% to 8% of those with prophylaxis. In this scenario, this paper had as objective to present the primary and secondary prophylactic methods to control gastrointestinal bleedings in Emergency Medicine, as well as your indications based on the best actual evidences. CONTENTS: Narrative bounded between the years 1970 to 2010, with search articles and abstracts available on databases such as Scielo, LILACS, Medline, Pubmed, Sumsearch, National Guideline Clearinghouse, as well as books related to area of critical care medicine and emergency. CONCLUSION: In the management of stress ulcers are used H2 receptor antagonists (AR2H) as a method of choice, followed by sucralfate, antacids and proton pump inhibitors (PPIs). In gastrointestinal bleeding are used preferentially IBPs and in ruptures of esophageal varices, sclerotherapy and elastic bandages. In these cases, rebleeding can be prevented with beta-blockers and nitrates.

Anaphylaxis Induced by Intravenous Ranitidine Injection: 2 Case Reports / 대한구급학회지

Histamine type 2 (H2) receptor antagonists are widely used for stress ulcer prophylaxis in critical and postoperative care. Though ranitidine is one of the most commonly used H2 receptor antagonists, with a low incidence of adverse reactions, a few anaphylactic reactions associated with ranitidine have been reported. This report describes 2 additional cases of anaphylaxis induced by ranitidine used for stress ulcer prophylaxis.

Rebamipide May Be Comparable to H2 Receptor Antagonist in Healing Iatrogenic Gastric Ulcers Created by Endoscopic Mucosal Resection: A Prospective Randomized Pilot Study

Endoscopic mucosal resection (EMR) results in the formation of iatrogenic gastric ulcers and the optimal treatments for such ulcers are still unclear. We aimed to evaluate the efficacy of rebamipide in the management of EMR-induced ulcers by comparing it with an H2 receptor antagonist. After EMR, patients were randomly assigned into either rebamipide or famotidine groups. All patients received a one-week lansoprazole 30 mg q.d. therapy followed by three-week famotidine (20 mg b.i.d.) or rebamipide (100 mg t.i.d.) therapy. Four weeks after the treatments, ulcer sizes, stages, bleeding rates, and ulcer-related symptoms were compared using endoscopy and a questionnaire. A total of 63 patients were enrolled in this study. Finally, 51 patients were analyzed, 26 in rebamipide and 25 in famotidine group. Baseline characteristics were not significantly different between the two groups. Four weeks after EMR, the two groups were comparable in terms of ulcer reduction ratio (P=0.297), and ulcer stage (P=1.000). Moreover, no difference was observed with regard to ulcer-related symptoms, drug compliance, adverse drug event rates, and bleeding rates. Our data suggest that rebamipide is not inferior to famotidine in healing iatrogenic gastric ulcers, and could be a therapeutic option in the treatment of such ulcers.

Therapeutic Effect of Low-Dose Omeprazole vs. Standard-Dose Ranitidine in Mild to Moderate Reflux Esophagitis / 대한소화기학회지

BACKGROUND/AIMS: Proton pump inhibitors (PPI) and H2-receptor antagonists (H2RA) are commonly prescribed for the treatment of mild to moderate reflux esophagitis (MMRE). There remains great controversy in their usefulness as the first choice and the appropriateness. We prospectively compared the efficacy and safety of the 8-week low-dose PPI vs. standard-dose H2RA in MMRE. METHODS: One hundred patients with MMRE were randomized to receive either low-dose of omeprazole (L-OMP: 10 mg, q.d.) or standard-dose of ranitidine (S-H2RA: 150 mg, b.i.d.) for 8 weeks. The H. pylori status using rapid urease test, histological examination and culture, reflux esophagitis (RE) grading, gastrointestinal symptoms using 4-point scale, adverse event and the standard laboratory examination were assessed at baseline and 8-week end point of therapy. RESULTS: Improvement rate of RE [intention to treat (n=82)/per protocol (n=72)] were shown in 69.1%/63.9% for L-OMP and 65.0%/63.9% for S-H2RA group (p=0.697, p=1.000). Complete healing rates of RE were 54.7%/50.0% for L-OMP and 42.5%/41.7% for S-H2RA. No significant difference in healing rate, the rapidity of symptom resolution, adverse events, and laboratory monitoring was found between the two groups. CONCLUSIONS: The low-dose omeprazole therapy produced similar healing rates and safety in the treatment of MMRE. In addition, L-OMP is advantageous in its once-a-day dosing and might be an alternative to S-H2RA, especially in Korean patients with MMRE.

The Comparative Study on the Efficacy of Ranitidine and Rabeprazole in Reflux Laryngitis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Reflux laryngitis gives rise to inflammatory change in the pharyngolaryngeal tissue with various otolaryngologic and respiratory symptoms. Histamine H2 receptor antagonists and H(+)-K(+)-Exchanging ATPase are currently used as therapeutic medications. However, the efficacy of those two drugs on reflux laryngitis has never been proven yet. Therefore, we intended to analyze and compare the efficacy of the two drugs on reflux laryngitis. MATERIALS AND METHOD: Among the patients who had visited the Department of Otolaryngology, those with the total score of greater than 6 and having more than 2 symptoms that score greater than 2, had undergone laryngoscopy. Of these, the patients who had shown greater than 7 on the Belafsky's Reflux Finding Score (RFS) were studied. The RAN (Ranitidine) group (59 subjects) with Ranitidine administered and RAB (Rabeprazole)group (66 subjects) with Rabeprazole were followed up for 12 weeks, and then the efficacy of each drug was evaluated at 2nd, 4th, and 12th week. Then, the Symptom Score Improvement (SSI) and RFS were compared and analyzed. RESULTS: In comparison the RAN group that had Histamine H2 receptor antagonists and prokinetic agents administered to the RAB group that had H(+)-K(+)-Exchanging ATPase and prokinetic agents administered for the improvement of symptoms caused by reflux laryngitis, no difference was observed till after the first 2 weeks. On the evaluation at 4th and 12th week, statistically higher therapeutic efficacy was shown to a great extent in the RAB group. The findings of laryngoscopy at the 12th week also showed higher therapeutic efficacy in the RAB group. In comparison of symptoms between the groups, there were significant differences in pharyngolaryngeal foreign body sense and chronic throat clearing, and laryngeal edema and injection as well. CONCLUSION: For therapy of reflux laryngitis patients with moderately severe symtpoms, the use of H(+)-K(+)-Exchanging ATPase and prokinetic agents were superior in improving symptoms and clinicopathologic findings of larynx than Histamine H2 receptor antagonists and prokinetic agents.

H2 Receptor Antagonists and Gastric Cancer in the Elderly: A Nested Case-Control Study / 예방의학회지

OBJECTIVE: To test if the intake of H2 receptor antagonists (H2-RAs) increases the risk of gastric cancer in the elderly. METHODS: The source population for this study was drawn from the responders to a questionnaire survey administered to the Korea Elderly Pharmacoepidemiological Cohort (KEPEC), who were beneficiaries of the Korean Medical Insurance Corporation, were at least 65 years old, and residing in Busan in 1993. The information on H2-RAs exposure was obtained from a drug prescription database compiled between Jan. 1993 and Dec. 1994. The cases consisted of 76 gastric cancer patients, as confirmed from the KMIC claims data, the National Cancer Registry and the Busan Cancer Registry. The follow-up period was from Jan. 1993 to Dec. 1998. Cancer free controls were randomly selected by 1:4 individual matching, which took in to consideration the year of birth and gender. Information on confounders was collected by a mail questionnaire survey. The odds ratios, and their 95% confidence intervals, were calculated using a conditional logistic regression model. RESULTS: After adjusting for a history of gastric ulcer symptoms, medication history, and body mass index, the adjusted OR (aOR) was 4.6 (95% CI=1.72-12.49). The odds ratio of long term use (more than 7 days) was 2.3 (95% CI=1.07-4.82). The odds ratio of short term use was 4.6 (95% CI=1.26-16.50). The odds ratio of parenteral use was 4.4 (95% CI=1.16-17.05) and combination use between the oral and parenteral routes (aOR, 16.8; 95% CI=1.21-233.24) had the high risk of gastric cancer. The aOR of cimetidine was 1.7 (95% CI=1.04-2.95). The aOR of ranitidine was 2.0 (95% CI=1.21-3.40). The aOR of famotidine was 1.7 (95% CI=0.98-2.80). CONCLUSION: The intake of H2-RAs might increase the risk of gastric cancer through achlorhydria in the elderly.

The Effects of Ranitidine (300mg) and Omeprazole (10, 20mg) on Gastroesophageal Reflux and Intragastric pH in Healthy Subjects / 대한소화관운동학회지

BACKGROUND/AIMS: This study was done to compare the effects of Omeprazole (OMD) 10 or 20 mg with Ranitidine(RAN) 300 mg on intragastric acidity and gastroesophageal reflux in healthy subjects. METHODS: Ten healthy male volunteers were studied after administrations of 5 days dosing with either RAN 300 mg, OMD 10 mg or 20 mg, once each morning. On the 5(th) day, intragastric pH and lower esophageal pH were measured by a dual channel antimony pH catheter for 10 hours. RESULTS: Gastroesophageal reflux was reduced after administrations of RAN 300 mg, OMD 10 mg or 20 mg (p 0.05). The gastric holding time of pH > 4 was significantly prolonged over fasting and postprandial periods after RAN 300 mg, OMD 10 mg or 20 mg administrations (p 0.05). OMD administrations (10 mg or 20 mg) exhibited a more potent effect on gastric acid suppression during the postprandial period than RAN 300 mg (p < 0.05). CONCLUSIONS: OMD 10 mg was as potent as RAN 300 mg on inhibition of gastric acid, but less potent than OMD 20 mg. There was no difference among the three drugs in regard to gastroesophageal reflux in healthy subjects.

Three Cases of Hepatitis Related to the Use of Famotidine and Ranitidine / 대한간학회지

H2-receptor blockers are widely used for therapy of peptic ulcer disease and gastroesophageal reflux disease. H2-receptor blockers infrequently cause adverse hepatic effects, and when they occur they are usually asymptomatic. There are several previous reports of liver injury related to ranitidine. Until now, only two cases of acute hepatitis associated with the use of famotidine were reported in the world. We report three cases of clinical hepatitis that followed administration of famotidine (2 cases) and ranitidine (1 case). First, a 54-year-old woman received famotidine, 40mg, daily for treatment of erosive gastritis. After 6 weeks of treatment with famotidine, jaundice and itching sense developed. Second, a 45-year-old man was hospitalized for jaundice. He had a long history of duodenal ulcer and had been intermittently treated with famotidine. He had 6 weeks of treatment with famotidine prior to admission. Third, a 19-year-old woman was hospitalized for nausea, vomiting and urticaria. She had a history of acute hepatitis B virus infection and was discharged 4 weeks prior to readmission. She had been received ranitidine, 300 mg, daily for treatment of gastritis. After 17 days of drug ingestion, whenever she had taken her medication, she developed these symptoms of nausea, vomiting and urticaria. Other causes of hepatitis were ruled out and all patients recovered after discontinuation of drug ingestion.

Three Cases of Hepatitis Related to the Use of Famotidine and Ranitidine / 대한간학회지

H2-receptor blockers are widely used for therapy of peptic ulcer disease and gastroesophageal reflux disease. H2-receptor blockers infrequently cause adverse hepatic effects, and when they occur they are usually asymptomatic. There are several previous reports of liver injury related to ranitidine. Until now, only two cases of acute hepatitis associated with the use of famotidine were reported in the world. We report three cases of clinical hepatitis that followed administration of famotidine (2 cases) and ranitidine (1 case). First, a 54-year-old woman received famotidine, 40mg, daily for treatment of erosive gastritis. After 6 weeks of treatment with famotidine, jaundice and itching sense developed. Second, a 45-year-old man was hospitalized for jaundice. He had a long history of duodenal ulcer and had been intermittently treated with famotidine. He had 6 weeks of treatment with famotidine prior to admission. Third, a 19-year-old woman was hospitalized for nausea, vomiting and urticaria. She had a history of acute hepatitis B virus infection and was discharged 4 weeks prior to readmission. She had been received ranitidine, 300 mg, daily for treatment of gastritis. After 17 days of drug ingestion, whenever she had taken her medication, she developed these symptoms of nausea, vomiting and urticaria. Other causes of hepatitis were ruled out and all patients recovered after discontinuation of drug ingestion.

Pressor Effect of Intracerebroventricular Diphenhydramine and Ranitidine in Rabbits

This study was undertaken to observe the effects of centrally administred antihistamines on the blood pressure. Diphenhydramine(DPH), a H1-receptor antagonist, and ranitidine(RAN), a H2-receptor antagonist were administered intracerebroventricularly(icv) on urethane-anesthetized rabbits. 1) Both DPH and RAN administered intraccebroventricularly increased blood pressure, however the intravenous(iv) adminstration of them did not affect blood pressure. The pressor response to icv DPH was dose-dependent, but that to icv RAN was not. 2) The pressor response to icv DPH(1mg) was either markedly attenuated or reversed to depressor response by the pretreatment with icv phentolamine(250,500ug), and iv chlorisondamine(0.1, 1mg/Kg) and iv phenoxybenzamine(1mg/Kg). In cord-sectioned rabbtis, icv RAN) 1mg) did not produce pressor response. 3) The pressor responsr to icv RAN(1mg) was not affected by the pretreatment with icv phentolamine(500ug), iv chlorisondamin(1mg/Kg) and iv phenoxybenzamine(1mg/Kg), and iv phenoxybenzamine(1mg/Kg). RAN also producted pressor response in cordsectioned rabbits. These results suggest that the pressor response to icv DPH is elecited by increasing peripheral sympathetic tone via the stimulation of central alpha-adrenoreceptors and the pressor response to icv RAN is produced by releasing some humoral facotr which can increase blood pressure.

Effect of H2-receptor Blockers on Antagonism of Vecuronium Neuromuscular Blockade / 대한마취과학회지

Recently, several studies have shown that the H2-receptor blockers can cause inhibition of cholinesstrase and neuromuscular blockade which suggest involvement of ion-chennel block in relatively large experimental dose. We investigated the effect of three H2-receptor blockers cimetidine, ranitidine, and famotidine on antagonism of vecuronium neuromuscular blockade. Forty ASA class 1 or 2 adult patients were studied. All patients were premedicated with hydroxyzine 1.5mg/kg and glycopyrrolat 0.2mg IM, 1hour before induction. Anesthesia was induced with thiopental sodium 5~6 mg/kg, succinylcholine 1mg/kg and was maintained with 02-N20(50%)-enflurane. Intraoperative muscle relaxation was maintained below 5% of control twitch height on TOF stimulation by combined bolus IV(0.08mg/kg) and contino=uous infusion(0.08mg/kg/hour) of vecuronium. Patients were divided into four groups according to use of H2-receptor blocker just after stop of vecuronium infusion as follows: Control group (n=10): no use of H2-receptor blocker, Cimetidine group (n=10): cimetidine 200mg IV, Rantitidine group (n=10): rantidine 50 mg IV, Famotidine group (n=10): famotidine 50 mg IV. Reversal of neuromuscular blockade with neostigmine(0.04mg/kg) was performed at 10% recovery of first twitch height (T1) in all cases. The recovery of T1 and T4 ratio after reversal was measured at 1min, interval for 20 min. The results were as follows: 1) The recovery of twitch height after administration of neostigmine was prolonged in all three H2-receptor blocker groups as compared to control group, but statistical significance was noted only in Famotidine group (p<0.05). 2) The changes of heart rate and mean arterial pressure after administration of neostigmine were similar in all groups.

The Effect of H2-receptor Blockers on the Duration of Action of Succinylcholine and Vecuronium / 대한마취과학회지

Cimetidine, and H2-receptor blocker, is associated with a direct inhibition of liver microsomal enzymes and a decrease in liver blood flow which results in a variety of clinically significant drug interactions, but its effects on the action of muscle relaxants have not been established. Recently, Kambam et al(1987) reported that the duraion of action of succinylcholine was prolonged 2~2.5 times by cimetidine. The effects of cimetidine, ranitidine, and famotidine, on duration of action of succinylcholine and vecuronium were studied. Sixty ASA class 1 or 2 patients scheduled for elective exploratory laprotomies were randomly divided into two groups as follows: Succinylcholine Group(n=40, 1mg/kg) control group(n=10), cimetidine group(n=10): 300mg ph hs & 1 hour before induction, ranitidine group(n=10): 150mg po hs & 1 hour before induction, famotidine group(n=10) : 40mg po hs only. Vecuronimu Group(n=20, 0.08mg/kg) control group(n=10), famotidine group(n=10): 40 mg po hs only. All patients were premedicated with hydroxyzine(1.5mg/kg) and Robinul 0.2mg IM, 1 hour before anesthesia. Anesthesia was induced with thiopental sodium 5~6mg/kg and succinylcholine 1mg/kg or vecuronium 0.08mg/kg. Tracheal intubation was performed at 75~!00% block as monitored by train-of-four stimulation of the ulnar nerve at 2Hz, 20 seconds apart(ABM, Datex). Anesthesis was maintained with 50% nitrous oxide, oxygen, and 2% enflurane. The duration of action of the muscle relaxants was measured from injection of muscle relaxant to the time of 25% recovery of first twitch height on train-of-four stimulation. The results were as follows: 1) The duration of succinylcholine was prolonged significantly by the H2-receptor blockers, 8.3+/-1.49 minutes with cimetidine, 9.8+/-1.98 minutes with ranitidine, and 10.3+/-2.48 minutes in the famotidine group as compared to 6.9+/-1.43 minutes in the control(p0.05).

The effect of histamine H_2 receptor blocker famotidine on the gastric function and ulcer-index in rats of hemorrhagic stress / 中国病理生理杂志

The effect of a histamine H_2 receptor blocker-famotidine on the changes of blood volume and oxygen saturation in the gastric mucosa of rats under hemorragic stress was studied with reflectance spectrophotometry. The effects of famotidine on the volume of gastric juice and gastric acid excreted and also stress uIceration were studied at the same time. Before hemorrhage, famotidine (3mg. kg~(-1), 8mg.kg~(-1iv)) did not alter the blood volume and oxygen saturation in the gastric mucosa. Under hemorrhagic state, famotidine could prevent the decrease of blood volume and oxygen saturation in the gastric mucosa and decreased the volume of gastric juice and gastric acid secretions, and could also protect the rats from formation of stress ulcer.