Inclusion Criteria:

1. Patients with multiple myeloma and lymphoma deemed by the treating institution to be candidates for high dose chemotherapy and autologous hematopoietic stem cell transplant.
2. Both males and females are eligible.
3. Patients should be 18 years old; multiple myeloma patients up to age 75 and lymphoma patients up to age 65 are eligible.
4. Patients with Karnofsky performance status of 60% or better.
5. Patients should have at least 2.5 x 106 cyropreserved CD34+ cells per kilogram available for transplantation.
6. Patients with adequate bone marrow function as defined as ANC ≥1000 cells/mm3 , platelet ≥ 75,000 cells/mm3.
7. Lymphoma patient must have adequate renal function as defined by a calculated creatinine clearance of 50% measured in ml/min.
8. The criteria for renal function does not apply for multiple myeloma patients. Multiple myeloma patients undergoing hemodialysis are eligible.
9. All patients must have a MUGA scan indicating a left ventricular ejection fraction (LVEF) of greater or equal to 48% within 42 days prior to registration.
10. Patients must have adequate pulmonary function as defined by room air pulse oximetry equal to or greater than 93%, and pulmonary function tests (FEV1 and DLCO) equal to or greater than 50% of predicted values.
11. Patients with adequate hepatic function as defined by serum bilirubin lower than 2.5 mg/dL and liver function tests to not exceed greater than 1.5x of the institutions ULN.
12. All patients must be informed of the investigational nature of this study and must sign and give written informed consent in accordance with the institutional and federal guidelines.
13. Patients must be able to complete the anti-emesis assessment questionnaire. A Spanish questionnaire will be available for Hispanic-speaking patients.

Exclusion Criteria:

1. Patients with nausea and have emetic episodes, and are receiving any anti-emetic medication taken within 24 hours of receiving antibiotics.
2. Active infection involving intravenous antibiotics.
3. Patients with known active hepatitis B and/or hepatitis C infections are excluded.
4. Patients with known HIV infection.
5. Primary or secondary brain neoplasms with increased intracranial pressure.
6. Received intrathecal chemotherapy within 24 hours of first dose of conditioning chemotherapy.
7. Patients who are nursing mothers or pregnant. Females of childbearing age are required to have a negative serum B-HCG pregnancy test 24 hours prior to enrollment on the study.
8. Patients with previous malignancies at other sites except surgically treated nonmelanomatous skin cancers, prostate cancer or superficial cervical cancers, or other cancer from which the patient had been disease free for 5 or more years.
9. Patients with uncontrolled medical problems such as diabetes mellitus, cardiac (i.e. congestive heart failure, coronary heart disease, arrhythmias), pulmonary hepatic and renal disease unless renal insufficiency is felt to be secondary to multiple myeloma,
10. Myocardial infarction within 6 months of enrollment in the study.
11. Major surgery within 4 weeks of enrollment.
12. Morbid obesity (BMI>40)
13. Patients with psychiatric or central nervous systems disorders interfering with ability to comply with study protocol.
14. Patients receiving therapeutic anticoagulant therapy for venous thromboembolic episode or other hypercoaguable states. Coumadin at 1 mg as prophylaxis for central venous catheter is allowed.
15. Known hypersensitivity to 5-HT3 antagonists and Aprepitant and their components.
16. Use of non-prescription and herbal-type medications within 72 hours of enrollment on the study. Their use are not allowed during the study.

Multivitamins, nutritional supplements such as Boost, and other electrolyte replacements are allowed.