t be exceeded.
Drug Abuse and Dependence
Animal studies have shown that ondansetron is not discriminated as a benzodiazepine nor does it substitute for benzodiazepines in direct addiction studies.
Overdosage
There is no specific antidote for ondansetron overdose. Patients should be managed with appropriate supportive therapy. Individual intravenous doses as large as 150 mg and total daily intravenous doses as large as 252 mg have been inadvertently administered without significant adverse events. These doses are more than 10 times the recommended daily dose.
In addition to the adverse events listed above, the following events have been described in the setting of ondansetron overdose: “Sudden blindness” (amaurosis) of 2 to 3 minutes’ duration plus severe constipation occurred in 1 patient that was administered 72 mg of ondansetron intravenously as a single dose. Hypotension (and faintness) occurred in a patient that took 48 mg of ondansetron HCl tablets. Following infusion of 32 mg over only a 4-minute period, a vasovagal episode with transient second-degree heart block was observed. In all instances, the events resolved completely.
Zuplenz Description
Zuplenz (ondansetron) oral soluble film is a white opaque orally dissolving film designed to be applied on top of the tongue where it will dissolve in 4 to 20 seconds and then is swallowed with saliva.
Zuplenz does not require water to aid dissolution or swallowing.
The active ingredient in Zuplenz is ondansetron base, the racemic form of ondansetron, and a selective blocking agent of the serotonin 5-HT 3 receptor type. Chemically it is (±) 1, 2, 3, 9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazol-1-yl)methyl]-4H-carbazol-4-one.
The empirical formula is C 18H19N3O representing a molecular weight of 293.3. Each 4 mg Zuplenz oral soluble film for oral administration contains 4 mg ondansetron base. Each 8 mg Zuplenz oral soluble film for oral administration contains 8 mg ondansetron base. Each Zuplenz oral soluble film also contains the inactive ingredients butylated hydroxyltoluene, calcium carbonate, colloidal silicon dioxide, erythritol, hydroxypropyl methylcellulose, monoammonium glycyrrhizinate, peppermint flavor, polyethylene oxide, sodium bicarbonate, sucralose, titanium dioxide and xanthan gum.
Zuplenz - Clinical Pharmacology
Mechanism of Action Section
Ondansetron is a selective 5-HT 3 receptor antagonist. While its mechanism of action has not been fully characterized, ondansetron is not a dopamine-receptor antagonist. Serotonin receptors of the 5-HT3 type are present both peripherally on vagal nerve terminals and centrally in the chemoreceptor trigger zone of the area postrema. It is not certain whether ondansetron’s antiemetic action is mediated centrally, peripherally, or in both sites. However, cytotoxic chemotherapy appears to be associated with release of serotonin from the enterochromaffin cells of the small intestine. In humans, urinary 5-HIAA (5-hydroxyindoleacetic acid) excretion increases after cisplatin administration in parallel with the onset of emesis. The released serotonin may stimulate the vagal afferents through the 5-HT3 receptors and initiate the vomiting reflex.
Pharmacodynamics
In normal volunteers, single intravenous doses of 0.15 mg/kg of ondansetron had no effect on esophageal motility, gastric motility, lower esophageal sphincter pressure, or small intestinal transit t |
