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Dear Sir ,
I am sorry that your wife is having to endure such suffering to treat her
condition . From looking at the list of drugs that have been tried so far ,a
couple of possibilities come to mind . These could be discussed with her
Oncologist .
Sometime combinations of medications work where single agents have failed.An
example of a regimen used would include a dopamine antagonist with other
agents(decadron ) having no dopamine blocking effect in conjunction with
something to prevent dystonic reactions . The regimen you described fits that
description , with the exception of the agent to prevent dystonic reaction and
evidently that is not an issue with that particular dosage of phenergan.
It may take more fine tuning to make a certain regimen work . If the
doctor is aware it is not significantly controling symptoms , it might be
possible to adjust dosages and or add the dronabinol or zofran back into the
currents drug regimen .
Another possibility is to substitute a different dopaminergic
antagonist for the phenergan and if needed add diphenhydramine .
Several drugs that fall in the class of the Kytril and Zofran are
Dolasetron, Batanopride , and Tropisetron . These are considered seotonin
antagonists and are not known for treatment of delayed symptoms .The last two
were being evaluated sometime ago and I do not know of their current status in
that evaluation for usage . I attached a file about Dolasetron .
Several papers are out there on guided imagery and hypnosis but I
don't have them at hand .
This is all nothing but cook book medicine on my part and would not be
appropriate for me to make these suggestions , except under the premise that
you should be aware there are options and there is hope . Please talk to the
doctor and don't be afraid to say we need to do something more . The doctor
would be able to fit the specifics of the treatment to the specific patient
variables involved . The standard measure for predicting nausea and vomiting
is the higher the fractional daily dose and the greater the amount of tissue
involved the higher the side effects . He aslo can look for other conditions
that would be causing or influencing the nausea .
Take care and hang tough
Joseph Cane
Title: Dolasetron for Chemotherapy-induced Nausea
See the following entries in DrugDB for more information about drugs mentioned in this article.
dolasetron
ondansetron
granisetron
See the |
Dolasetron for Chemotherapy-induced NauseaFrom issue No. 242 (November, 1997 Special Edition) of Medical Sciences Bulletin
Following oral or intravenous administration, dolasetron is converted to its active metabolite, hydrodolasetron. Peak plasma levels occur in approximately 30 minutes following intravenous administration and about 1 hour following oral administration. The oral bioavailability of dolasetron ranges anywhere from 70-89% and is not affected by food. Hydrodolasetron is further metabolized by the liver into glucuronide and sulfate conjugates and excreted via the urine (59%) and the feces (25%). Dolasetron has a elimination half-life of 4-8 hours following intravenous administration and an elimination half-life of 5-10 hours following oral administration.
In another study performed by Kris et al, doses of 1.8 mg/kg, 2.4 mg/kg, 3 mg/kg and 5 mg/kg were administered 30 minutes prior to a cisplatin regimen as a 20 minute infusion. Vomiting was absent in 24%, 48%, 52% and 50% of the patients respectively. Also, nausea was not seen in 29%, 24%, 24%, and 32% of the patients respectively. The mean time to the first episode of vomiting for doses greater than 1.8 mg/kg was 20-24 hours. Audhuy et al performed a randomized, double-blind, multicenter study in 474 patients in which they evaluated the efficacy of dolasetron 1.8 mg, dolasetron 2.4 mg, and granisetron 3 mg. They noted that there was no significant difference seen between the 3 regimens. Complete response was obtained in 54% of the patients who were receiving dolasetron 1.8 mg/kg, 47% of the patients who were receiving 2.4 mg/kg, and 48% of the patients who were receiving granisetron. In a randomized, double-blind multicenter study performed by the dolasetron chemotherapy-induced emesis group, 609 patients were enrolled. These patients were randomized to receive one of three treatments: dolasetron 1.8 mg/kg, dolasetron 2.4 mg/kg or ondansetron 32 mg. Dolasetron was as effective as ondansetron in patients who were receiving high (91 mg/m2 or greater) or medium doses (70-90 mg/m2) of cisplatin. In clinical trials that evaluated the use of dolasetron, headache and diarrhea were the most prominent adverse effects. Other adverse effects that were observed included dizziness, fatigue and abnormal liver functions. Nausea and vomiting are common adverse effects of chemotherapy. At times these adverse effects can be so severe that they may prevent the use of that chemotherapeutic agent. Minimization of these unwanted effects may convince a patient to continue to remain compliant with their chemotherapeutic regimen. Since the introduction of ondansetron, serotonin antagonists have become the gold standard in managing chemotherapy induced nausea and vomiting. Clinical trials indicate that dolasetron is effective in controlling nausea and vomiting. In addition, it has been shown to be as effective as ondansetron and granisetron. Hence, dolasetron can serve as yet another option in the management of these unfortunate adverse effects.
© 1997 VirSci Corporation.
All rights reserved.
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