Safety and Efficacy Study of Axid Use in Infants Suffering From Gastroesophageal Reflux Disease (GERD)

Inclusion Criteria: * Male or female outpatients age 30 days up to 1 year at Visit 1. * Subjects must have a documented medical diagnosis of gastroesophageal reflux disease (GERD), confirmed by either endoscopy or pH monitoring, or by evaluation of baseline symptoms. * Subjects must be greater than the 3rd percentile of weight and height for their age. * Parents/guardians are competent and willing to provide consent and sign and date the institutional review board (IRB) approved consent form. * Parents/guardians are willing to adhere to study requirements, including applying the conservative GERD management methods. * Conservative GERD management methods have failed to adequately control GERD symptoms by Visit 2. * Parent/guardian and infant live in the same household. * Qualifying caregiver questionnaire score at Visits 1 \& 2. Exclusion Criteria: * Any known esophageal disease or disorder, other than reflux esophagitis. * Any active gastroduodenal ulceration, or clinical or endoscopic evidence of active gastrointestinal bleeding. * Any prior esophageal or gastric surgery. * Concurrent serious systemic disorders, including chronic respiratory disease, chronic neurologic disease, chronic renal disease, chronic liver disease. * Subjects with clinically significant abnormal laboratory findings at screening. * Premature infants \< 37 weeks gestation at birth. * Infants with prior neonatal intensive care unit admission for any reason. * Hematemesis or apparent life-threatening events (ALTE). * Concurrent treatment with any chronic medication except by permission of the study sponsor. * Treatment with a histamine 2 receptor antagonist (H2RA), antacid, sucralfate, prostaglandin, or motility agent within 3 days before Visit 1; treatment with a proton pump inhibitor within 7 days before Visit 1. * Requirement or likely requirement for a medical procedure or surgery during the study. * Known hypersensitivity to an H2RA including nizatidine. * Receipt of any investigational agent within the previous 30 days before randomization. * Poor medical or psychiatric risks for therapy with an investigational drug, in the opinion of the investigator. * Any condition in parent/guardian associated with poor subject compliance e.g., substance abuse); inability of parent/guardian to return for scheduled visits with their child.