AIM:To assess the efficacy and safety of a compoundcontaining alginic acid plus antacid(Topaal)comparedto equal-strength antacid(Nacid)in patients with en-doscopy-negative reflux disease(ENRD).METHODS:A total of 121 patients with ENRD were ran-domized to receive Topaal(65 patients)or Nacid(56patients)for 6 weeks,with a consultation every 3 weeks.The primary end-point assessment was the change inthe severity of heartburn as evaluated using a visualanalog scale(VAS)at 6 weeks.The secondary end-pointassessments were the VAS at 3 weeks,the change offrequency of the reflux symptom,the change of qualityof life and the adverse effects.RESULTS:Demographics of randomized subjects ineach treatment group were comparable except thatthe Topaal group included more males.The baselinecharacteristics between the groups were similar.After 6weeks of treatment,the reduction of VAS of heartburnwas more prominent in the Topaal group(-6.29 cmvs-4.11 cm).At the 3~(rd) week,Topaal group showedgreater reduction of VAS for heartburn(P= 0.0016),regurgitation(P=0.0006),vomiting(P=0.0373),andbelching(P<0.0001).The patients of the Topaal grouphad lower frequency of heartburn(P= 0.0015)and pain(P=0.0163)at the end of the 6-week treatment period.From the doctor’s point of view,the Topaal group alsoshowed significant reduction in the severity of heart-burn(P=0.0020),regurgitation(P=0.0081),vomiting(P=0.0182),and belching(P=0.0018)at the end of thetreatment.The improvement of the quality of life was more remarkable in the Topaal group at the end of the6-week treatment period(P<0.0001).For the adverseeffect,there was no difference in both the groups.CONCLUSION:Topaal is more effective than Nacid forthe treatment of symptoms presented by patients withENRD. AIM: To assess the efficacy and safety of a compoundcontaining alginic acid plus antacid (Topaal) comparedto equal-strength antacid (Nacid) in patients with en-doscopy-negative reflux disease (ENRD) .METHODS: A total of 121 patients with ENRD were ran-domized to receive Topaal (65 patients) or Nacid (56 patients) for 6 weeks, with a consultation every 3 weeks. The primary end-point assessment was the change inthe severity of heartburn as evaluated using a visualanalog scale (VAS) at 6 weeks.The secondary end-pointassessments were the VAS at 3 weeks, the change offrequency of the reflux symptom, the change of qualityof life and the adverse effects .RESULTS: Demographics of randomized subjects ineach treatment group were comparable except that the Topaal group included more males The baseline characteristics between the groups were similar. After 6 weeks of treatment, the reduction of VAS of heartburn was more prominent in the Topaal group (-6.29 cmvs-4.11 cm) .A the the 3rd ~ (rd) week, Topaal group showedgreater reduction of VAS for heartburn (P = 0.0016), regurgitation (P = 0.0006), vomiting (P = 0.0373), andbellexing (P <0.0001) .The patients of the Topaal grouphad lower frequency of heartburn = 0.0163) at the end of the 6-week treatment period. From the doctor’s point of view, the Topaal group alsoshowed significant reduction in the severity of heart-burn (P = 0.0020), regurgitation (P = 0.0081) = 0.0182), and belching (P = 0.0018) at the end of the treatment. Improvement of the quality of life was more remarkable in the Topaal group at the end of the 6-week treatment period (P <0.0001) .For the adverse effect, there was no difference in both the groups. CONCLUSION: Topaal is more effective than Nacid forthe treatment of symptoms presented by patients with ENRD.