Ondansetron

Abstract

The use of ondansetron, a selective serotonin 5-HT3 receptor antagonist, is well established in patients with nausea and vomiting associated with cancer chemotherapy, radiotherapy or anaesthesia and surgery. The wide distribution of 5-HT3 receptors in the body and the role of these receptors in disease have provided the rationale for investigation of ondansetron in novel applications. Preliminary data have shown ondansetron to have clinical benefit in patients with nausea and vomiting associated with drug overdosage or poisoning, anti-infective or antidepressant therapies, uraemia or neurological trauma, and in patients with pruritus. Patients with gastrointestinal motility disorders (e.g. carcinoid syndrome, irritable bowel syndrome, diarrhoea associated with cryptosporidiosis or diabetes, and chronic refractory diarrhoea) have also shown some improvement when treated with ondansetron, as have patients with certain pain or CNS-related disorders [e.g. alcohol (ethanol) dependence, opiate withdrawal, vertigo, cerebellar tremor and Parkinson's disease treatment-related psychosis]. In contrast to conventional antiemetics, ondansetron is generally well tolerated with a lower incidence of sedation and only isolated case reports of extrapyramidal reactions. Furthermore, unlike dopamine receptor-blocking neuroleptics, ondansetron does not appear to worsen the symptoms of Parkinson's disease. Thus, in addition to its established indications, preliminary results suggest that ondansetron may be beneficial in a number of novel applications. This drug may represent a treatment alternative in patients with refractory disease, or an effective treatment of conditions for which current therapies are either poorly tolerated or not available. Further investigation of ondansetron in a range of potential new applications appears to be warranted.

Extrapyramidal side effects after metoclopramide administration in a post-anesthesia care unit -A case report-

“…However, although ondansetron does not bind to dopamine receptors, it does play an important role in dopaminergic transmission by reducing mesolimbic dopamine activity [11]. Our patient also used pregabalin before surgery, and pregabalin binds with high affinity to voltage-gated calcium channels in central nervous system and modulates the calcium-dependent releases of several neurotransmitters [12].…”

Assessment of Ondansetron-Associated Hypokalemia in Pediatric Oncology Patients

“…Several pharmacokinetic parameters were considered in this discussion [16, 17]. Pharmacokinetic data suggests that oral absorption of ondansetron is 100%, although bioavailability is reduced as low as 50% in the general population due to first pass metabolism in the liver.…”

Comparison of Alcoholism Subtypes as Moderators of the Response to Sertraline Treatment

“…Although Roache et al (2008) also found that age of onset was a better moderator of treatment response than the cluster-derived subtypes, in that study the differences seen between the two subtyping approaches were more evident than those seen here. This may reflect differences in the effects of the medications used, since sertraline has direct effects on serotonin reuptake via the serotonin transporter with secondary effects on postsynaptic receptors (McRae and Brady 2001), while the primary effects of ondansetron are on serotonin-3 receptors (Wilde and Markham 1996), with other postsynaptic receptors being affected as well (McNulty 2007). …”