Ranitidine is a widely used histamine-2-receptor antagonist and it is usually well tolerated by patients with an excellent safety record. Anaphylactic reaction to ranitidine is rare event. We report here on 2 cases with anaphylactic reaction after the intravenous administration of ranitidine in an emergency medical center. Awareness of this rare, but life threatening adverse reaction to a commonly used ranitidine can help physicians avoid being caught unaware when they experience this medical situation. Although the incidences of anaphylactic reactions induced by these drugs are low, clinicians should be aware of this possibility of life threatening risk of anaphylactic reaction when administering ranitidine. Furthermore, the possibility of cross reactivity between drugs in the same antihistamine group should be considered. (ED note: please check the part in the yellow.)
Administration, Intravenous ; Anaphylaxis ; Emergencies ; Histamine H2 Antagonists ; Humans ; Incidence ; Ranitidine

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.
Adolescent ; Adult ; Aged ; Anti-Ulcer Agents/*administration & dosage ; Comparative Study ; English Abstract ; Esophagitis, Peptic/*drug therapy/pathology ; Female ; Histamine H2 Antagonists/*administration & dosage ; Humans ; Male ; Middle Aged ; Omeprazole/*administration & dosage ; Ranitidine/*administration & dosage

This prospective, randomized, double-blinded study was performed to evaluate the effects of intravenous metoclopramide and ranitidine on preoperative gastric contents in outpatients receiving intravenous anesthesia for laparoscopic gynecologic surgery. Fifteen minutes before the induction of anesthesia, the Z-M group (n=20) received 50mg ranitidine and 10mg metoclopramide intravenously and the control group (n=20) received the same volume of normal saline. Before the surgery, a 14-F multiorifice nasogastric tube was inserted to aspirate the gastric contents of patients under sedation with propofol and midazolam. The mean pH values of the gastric fluid were 2.7+/-2.0 (SD) [median 1.6 (range: 1.2-7.2)] in the control group, and 6.1+/-1.9 [median 6.8 (range 1.4-7.8)] in the Z-M group. The mean aspirated volumes (mL) were 15.3+/-10.4 (SD) [median 11.0 (range: 5.0-44.0)] in the control group, and 6.9+/-10.0 (SD) [median 4.5 (range: 0-38.0)] in the Z-M group. There were significantly more high-risk (gastric fluid volumes > 25mL and pH < 2.5) patients in the control group (4/20, 20%) than in the Z-M group (1/20, 5%). In conclusion, intravenous prophylactic ranitidine and metoclopramide may be an easy and useful method to decrease the volume while increasing the pH of gastric contents, and therefore may reduce the number of patients at risk for aspiration pneumonitis in ambulatory laparoscopic procedures who receive an anesthesia.
Stomach/*drug effects ; Risk Factors ; Ranitidine/*administration & dosage ; Preoperative Care ; Pneumonia, Aspiration/epidemiology/*prevention & control ; Metoclopramide/*administration & dosage ; Injections, Intravenous ; Humans ; Antiemetics/*administration & dosage ; Anti-Ulcer Agents/*administration & dosage ; Ambulatory Surgical Procedures ; Adult

This prospective, randomized, double-blinded study was performed to evaluate the effects of intravenous metoclopramide and ranitidine on preoperative gastric contents in outpatients receiving intravenous anesthesia for laparoscopic gynecologic surgery. Fifteen minutes before the induction of anesthesia, the Z-M group (n=20) received 50mg ranitidine and 10mg metoclopramide intravenously and the control group (n=20) received the same volume of normal saline. Before the surgery, a 14-F multiorifice nasogastric tube was inserted to aspirate the gastric contents of patients under sedation with propofol and midazolam. The mean pH values of the gastric fluid were 2.7+/-2.0 (SD) [median 1.6 (range: 1.2-7.2)] in the control group, and 6.1+/-1.9 [median 6.8 (range 1.4-7.8)] in the Z-M group. The mean aspirated volumes (mL) were 15.3+/-10.4 (SD) [median 11.0 (range: 5.0-44.0)] in the control group, and 6.9+/-10.0 (SD) [median 4.5 (range: 0-38.0)] in the Z-M group. There were significantly more high-risk (gastric fluid volumes > 25mL and pH < 2.5) patients in the control group (4/20, 20%) than in the Z-M group (1/20, 5%). In conclusion, intravenous prophylactic ranitidine and metoclopramide may be an easy and useful method to decrease the volume while increasing the pH of gastric contents, and therefore may reduce the number of patients at risk for aspiration pneumonitis in ambulatory laparoscopic procedures who receive an anesthesia.
Stomach/*drug effects ; Risk Factors ; Ranitidine/*administration & dosage ; Preoperative Care ; Pneumonia, Aspiration/epidemiology/*prevention & control ; Metoclopramide/*administration & dosage ; Injections, Intravenous ; Humans ; Antiemetics/*administration & dosage ; Anti-Ulcer Agents/*administration & dosage ; Ambulatory Surgical Procedures ; Adult

BACKGROUND: Children undergoing general anesthesia are at increased risk of aspiration pneumonia. Cimetidine and ranitidine, specific histamine (H2-receptor) antagonists, markedly reduce the acidity and volume of gastric content when given 2 3h preoperatively. A newer compound, famotidine, is a more specific antagonist that has no inhibitory effect on the drug metabolizing microsomal enzyme systems of the liver (cytochrome P-450), in contrast to cimetidine. An additional clinical advantage is a possible longer duration of action. The aim of this study is to evaluate the lowest effective dose of famotidine on gastric pH and volume in children. METHODS: Fifty-five children, aged 2 to 14 years (ASA physical status I-II) were divided into four groups (Group I:placebo, normal saline 10 ml, Group II:famotidine 0.1 mg/kg, Group III:famotidine 0.15 mg/kg, Group IV:famotidine 0.2 mg/kg.). Doses were administered intravenously 2 or 3 hours before the operation. Following induction with oxygen, enflurane and pentothal sodium, anesthesia was maintained with N2O/O2 and enflurane. A nasogastric tube was passed into the stomach and the gastric contents were aspirated in a uniform manner. Gastric volume was recorded and pH values were measured with pH meter. The incidence of high risk for aspiration pneumonia, defined as gastric pH < 2.5 and gastric fluid volume > 0.4 ml/kg of gastric juice, was measured in all groups. RESULTS: In the placebo group, 10 of 13 children (77%) had a pH < 2.5 and gastric volume > 0.4 ml/kg. Group II (famotidine 0.1 mg/kg) was not found to produce a significant increase in the gastric pH. Groups III and IV (famotidine 0.15 mg/kg and 0.2 mg/kg) were found to produce a significant increase in the gastric pH. The gastric juice volume was reduced in all famotidine groups, but was not statistically significant compared with the placebo group. The incidences of high risk for aspirationpneumonitis decreased in all famotidine groups. CONCLUSIONS: The results suggest that the preoperative intravenous administration of famotidine 0.15 mg/kg is enough to decrease both gastric juice acidity and volume in this high-risk group.
Administration, Intravenous ; Anesthesia ; Anesthesia, General ; Child* ; Cimetidine ; Enflurane ; Famotidine* ; Gastric Juice ; Histamine ; Humans ; Hydrogen-Ion Concentration* ; Incidence ; Liver ; Oxygen ; Pneumonia, Aspiration ; Ranitidine ; Sodium ; Stomach ; Thiopental

OBJECTIVE: To observe the effect of ranitidine on gastric acid, plasma endothelin, and calcitonin gene-related peptide (CGRP) in patients undergoing the brain operation, and to explore the possible pathogenesis of ranitidine on preventing from gastric mucosal injury under the stress. METHODS: Thirty patients who underwent brain surgery were randomly divided into 2 groups: Fifteen patients in the control group did not use ranitidine and the other 15 in the treatment group received ranitidine 150 mg intravenously twice daily besides the routine therapy. We continuously monitored the gastric pH value from 4 hours pre-operatively to 72 hours post-operatively in the 30 patients. We also determined the plasma endothelin and CGRP levels of the patients at the 4th hour pre-operatively and at the 4th, 24th, and 72nd hours post-operatively. RESULTS: In the control group there was no significant difference between the mean intra-gastric pH values pre-operatively and post-operatively (P> 0.05). In the treatment group the level of intra-gastric pH was much higher than that in the control group (P< 0.05). In the control group, the level of plasma endothelin significantly higher and the level of calcitonin gene-related peptide significantly lower than that pre-operatively (P< 0.01), but the level of plasma endothelin significantly was lower and the level of calcitonin gene-related peptide obviously higher in the post-operative treatment group than that pre-operatively (P< 0.01). CONCLUSION The brain operation obviously influences the endogenous plasma endothelin and CGRP levels, but its influence on the intra-gastric acid is not visible. Ranitidine can obviously decrease the level of intra-gastric acid, and improve the macrocirculation of gastric mucous membrane by decreasing ET and increasing the CGRP level.
Adult ; Anti-Ulcer Agents ; administration & dosage ; therapeutic use ; Brain ; surgery ; Calcitonin Gene-Related Peptide ; blood ; Endothelin-1 ; blood ; Female ; Gastric Acid ; metabolism ; Humans ; Infusions, Intravenous ; Male ; Middle Aged ; Postoperative Complications ; prevention & control ; Ranitidine ; administration & dosage ; therapeutic use ; Stomach Ulcer ; prevention & control