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Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
The Effects of Increasing Doses of Ranitidine on Gastric pH in Children
Seema Khan1, Theresa M Shalaby, Susan R Orenstein
1Division of Pediatric Gastroenterology, University of Pittsburgh School of Medicine and Children's Hospital of Pittsburgh, Pittsburgh, Pennslyvania.
Insights
Higher doses of ranitidine (≥ 3 mg/kg) are more effective for controlling gastric acid in children with GERD, particularly for longer durations. Lower doses showed limited efficacy beyond six hours.
Area of Science:
- Pediatric Gastroenterology
- Pharmacology
- Clinical Trial Research
Background:
- Ranitidine is a common treatment for pediatric gastroesophageal reflux disease (GERD).
- Optimal weight-based dosing for ranitidine in children with GERD remains unclear.
- This study aimed to evaluate the efficacy of different ranitidine doses on gastric pH in pediatric GERD patients.
Purpose of the Study:
- To compare the effects of weight-based oral ranitidine doses on gastric pH in children diagnosed with GERD.
- To determine if higher ranitidine doses provide superior acid suppression compared to lower doses.
- To assess the duration of acid suppression provided by different ranitidine dosages.
Main Methods:
- A multi-center, prospective, randomized study involving children aged 4-11 years with clinical GERD.
- Gastric pH was measured after administering a fixed dose of ranitidine (Phase 1) and then weight-based doses (Phase 2).
- Two dose ranges were compared: Low Dose (< 3 mg/kg/dose) and High Dose (≥ 3 mg/kg/dose).
Main Results:
- While overall 6-hour gastric pH control was similar (50% vs. 57%), High Doses (≥ 3 mg/kg) significantly improved pH control in the last two hours (89% vs. 29%).
- All High Dose regimens maintained gastric pH > 4 for > 60% of the time during the final two hours, unlike Low Doses (P = 0.03).
- Extended monitoring showed High Dose ranitidine maintained gastric pH > 4 for over 40% of the total time in most patients.
Conclusions:
- Ranitidine doses of 3 mg/kg or higher are potentially necessary for effective acid suppression lasting longer than six hours in children with GERD.
- Higher weight-based doses of ranitidine demonstrate superior efficacy in maintaining gastric acid control.
- These findings suggest a need to reconsider current ranitidine dosing guidelines for pediatric GERD.
Background:
Ranitidine is widely used for gastroesophageal reflux disease (GERD) in children, but optimal dosing is unclear. We compared effects of weight-based doses of oral ranitidine on gastric pH in children with clinical GERD.
Methods:
Children ages 4-11 years with clinical GERD were enrolled in a multi-center prospective randomized study comparing a fixed dose of ranitidine (Zantac 75) with placebo after an overnight fast; gastric pH was measured for 6 h after the fixed dose (Phase 1). Of the six enrollees from our center, four received active drug during Phase 1; 12 h after the fixed dose, these four children received ranitidine 5 mg/kg (maximum 150 mg) and gastric pH was measured for another 6-12 hours (Phase 2). This report details the effects of two dose ranges (Low Dose, < 3 mg/kg/dose, and High Dose, ≥ 3 mg/kg/dose) on gastric pH in children.
Results:
The four children were 6.9-11.3 years old and weighed 20.4-49.5 kg. The Low Doses were 1.5-2.7 mg/kg; the High Doses were 3-5 mg/kg. Although the mean percentage of time with gastric pH > 4 during the entire 6 hours following dosing was similar after Low and High Dose (50% vs. 57%, NS), during the last two hours of this interval the mean percentage of time with gastric pH > 4 was only 29% for Low Dose vs. 89% for High Dose (P = 0.006). Moreover, during those two hours, none of the Low Doses kept gastric pH above 4 for > 60% of the time, while all of the High Doses kept pH above 4 for > 60% of the time (P = 0.03). In three of four patients who underwent extended (9-12 h) gastric pH monitoring after High Dose ranitidine, gastric pH was above 4 for more than 40% of total time.
Conclusions:
Doses of ranitidine ≥ 3 mg/kg/dose may be required for acid suppression lasting beyond 6 hours.
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