Intervention: Ondansetron hydrochloride dihydrate
Trial phase: Phase 3
SMILES: Cc1nccn1CC1CCc2c(c3ccccc3n2C)C1=O.Cl.O.O
Sex: All
Age groups: Child | Adult | Older Adult
Healthy volunteers: No
Participants at risk: 193
Group description: 1 tablet containing 6 mg immediate release and 18 mg sustained release ondansetron, once daily for up to 4 days.
Eligibility criteria:
Inclusion Criteria:

Patients must have vomited at least twice in the 4 hours preceding signing informed consent. A vomiting episode is defined as an episode of forceful expulsion of stomach contents. Retching if a patient has already emptied his or her gastric contents is also considered vomiting episode. A distinct episode is characterized by a clear break in vomiting activity of at least 5 minutes
Emesis must have been nonbloody (streaks of blood presumed due to force of retching are allowed)
All patients (and a parent or guardian for patients <age 18) must sign informed consent.

Exclusion Criteria:

Severe dehydration. Severe dehydration is defined as two or more of the following criteria in the presence of decreased intake and increased output due to vomiting or diarrhea: Absent or severely decreased urine output; weak pulse and/or low blood pressure; parched mucous membranes; lethargy, confusion, delirium or loss of consciousness
Signs and symptoms severe enough to require immediate parenteral hydration and/or parenteral antiemetic medication
Temperature>39.0
Likely etiologies for acute vomiting and diarrhea other than acute infectious or toxic gastroenteritis or gastritis. This includes signs of an acute abdomen, which may require surgical intervention
Chemically-induced gastroenteritis, e.g., from alcohol, other drugs of abuse or other irritant chemicals
Use within 24 hours of study entry of specific medication for treatment of nausea and/or vomiting, e.g., 5-HT3 antagonists or phenothiazines, or receipt of any IV fluid for any reason. Nonspecific gastrointestinal remedies, such as antacids, proton pump inhibitors and homeopathic remedies, are permitted.
Congestive heart failure, bradyarrhythmia (baseline pulse<55/min), known long QT syndrome
Patient who have known QTc prolongation > 450 msec, noted on prior or screening ECG, or who are taking medication known to cause QT prolongation. Note: for current list of medications known to cause QT prolongation see: https://www.crediblemeds.org/healthcare-providers/drug-list/ Use list showing drugs with known risk TdP.
Known underlying disease which could affect assessment of hydration or modify outcome of treatment, e.g., renal failure, diabetes mellitus, liver disease, alcoholism. Patients with type 2 diet-controlled diabetes mellitus whose baseline blood glucose is <200 may be entered into the study
Abdominal surgery within the past 3 months
History of bariatric surgery or bowel obstruction at any time
Hypersensitivity or other known intolerance to ondansetron or other 5-HT3 antagonists
Patient has taken apomorphine within 24 hours of screening
Patient has previously participated in this study
Patient has participated in another interventional clinical trial, for any indication, in the past 30 days
For women of childbearing potential: documented or possible pregnancy.