[Olanzapine use in cancer patients for refractory vomiting]

Pharmaceutical Excipients and Drug Metabolism: A Mini-Review

Conclusions from previously reported articles have revealed that many commonly used pharmaceutical excipients, known to be pharmacologically inert, show effects on drug transporters and/or metabolic enzymes. Thus, the pharmacokinetics (absorption, distribution, metabolism and elimination) of active pharmaceutical ingredients are possibly altered because of their transport and metabolism modulation from the incorporated excipients. The aim of this review is to present studies on the interaction of various commonly-used excipients on pre-systemic metabolism by CYP450 enzymes. Excipients such as surfactants, polymers, fatty acids and solvents are discussed. Based on all the reported outcomes, the most potent inhibitors were found to be surfactants and the least effective were organic solvents. However, there are many factors that can influence the inhibition of CYP450, for instance type of excipient, concentration of excipient, type of CYP450 isoenzyme, incubation condition, etc. Such evidence will be very useful in dosage form design, so that the right formulation can be designed to maximize drug bioavailability, especially for poorly bioavailable drugs.

Olanzapine for chemotherapy-induced nausea and vomiting: a systematic review

PURPOSE

Newer drugs incorporated in prophylactic regimens for chemotherapy-induced nausea and vomiting (CINV) have resulted in significantly reduced rates of this feared complication of cytotoxic chemotherapy. However, both delayed chemotherapy-induced nausea and breakthrough CINV remain difficult areas of management and require novel treatment strategies. Recent randomized trial evidence has suggested that olanzapine, an atypical antipsychotic, may have a role in both the prevention and treatment of CINV. A systematic review was conducted to assess the efficacy of olanzapine in (a) preventing CINV in highly emetogenic chemotherapy (HEC) and moderately emetogenic chemotherapy (MEC) and (b) the treatment of breakthrough CINV. The toxicity of olanzapine in this setting was also reviewed.

METHODS

MEDLINE, Embase and Cochrane Database of Systematic Reviews databases were searched to identify all randomized clinical trials (RCTs) investigating olanzapine in patients receiving chemotherapy.

RESULTS

A total of 488 patients from three trials of CINV prophylaxis and 323 patients from three trials of breakthrough CINV were included. Regimens including olanzapine were associated with significant improvements in CINV prevention with both HEC and MEC. Single agent olanzapine for breakthrough nausea was superior to standard alternative options.

CONCLUSION

Data from RCTs support the use of an olanzapine containing combination regimen as an option for CINV prophylaxis and single agent olanzapine for the treatment of breakthrough CINV. In the included trials, the short duration of olanzapine appears safe and well tolerated.

Olanzapine and Betamethasone Are Effective for the Treatment of Nausea and Vomiting due to Metastatic Brain Tumors of Rectal Cancer

Brain lesions originating from metastasis of colorectal cancer represent 3–5% of all brain metastases and are relatively rare. Of all distant metastases of colorectal cancer, those to the liver are detected in 22–29% of cases, while those to the lungs are detected in 8–18% of cases. In contrast, brain metastasis is quite rare, with a reported incidence ranging from 0.4 to 1.8%. Treatments for metastatic brain tumors include surgery, radiotherapy, chemotherapy and supportive care with steroids, etc. Untreated patients exhibit a median survival of only approximately 1 month. The choice of treatment for brain metastasis depends on the number of lesions, the patient's general condition, nerve findings and presence of other metastatic lesions. We herein report the case of a 78-year-old male who presented with brain metastases originating from rectal carcinoma. He suffered from nausea, vomiting, anorexia and vertigo during body movement. He received antiemetics, glycerol and whole brain radiation therapy; however, these treatments proved ineffective. Olanzapine therapy was started at a dose of 1.25 mg every night. The persistent nausea disappeared the next day, and the frequency of vomiting subsequently decreased. The patient was able to consume solid food. Olanzapine is an antipsychotic that has recently been used as palliative therapy for refractory nausea and vomiting in patients receiving chemotherapy. We consider that olanzapine was helpful as a means of supportive care for the treatment of nausea and vomiting due to brain metastasis.