Aprepitant in Preventing Nausea and Vomiting in Patients Who Are Undergoing a Stem Cell Transplant

Inclusion:

* 18 years of age or greater
* must be scheduled for an autologous or allogeneic bone marrow or peripheral stem cell transplant
* Eastern Cooperative Oncology Group(ECOG) performance status \< or = 2
* patients must have signed informed consent
* must be able to swallow tablets and capsules
* must be receiving a cyclophosphamide containing regimen.

Exclusion:

* patient has known sensitivity to aprepitant, ondansetron, or dexamethasone
* patient has received another investigational drug in the past 30 days
* patient has had emesis or requires antiemetic agents in the 48 hours prior to beginning conditioning therapy
* patient has taken neurokinin-1 antagonists for 14 days prior to enrollment
* patient is pregnant, has a positive serum human chorionic gonadotropin(hCg) or is lactating
* patient has serum creatinine level \> or = 2\*ULN
* patient has severe hepatic insufficiency (Child-Pugh score \>9)
* patient drinks \> 5 drinks/day for the last year
* patient with concurrent illness requiring systemic corticosteroid use other than planned dexamethasone during conditioning therapy