Inclusion Criteria:

• Scheduled to receive FOLFOX chemotherapy with individual oxaliplatin doses of 85 mg/m^2 per cycle given in 2 week cycles (e.g. modified [m] FOLFOX6 or FOLFOX4)
• Adequate complete blood count (CBC) and creatinine values (per attending physician) obtained ≤ 28 days prior to registration
• Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0, 1 or 2
• Negative pregnancy test done ≤ 7 days prior to registration, for women of childbearing potential
• Ability to complete questionnaire(s) by themselves or with assistance
• Life expectancy ≥ 4 months
• Strong inhibitors of CYP3A4: > 5-fold increase in the plasma area under the curve (AUC) values or more than 80 % decrease in clearance
  • Indinavir (Crixivan®)
  • Nelfinavir (Viracept®)
  • Atazanavir (Reyataz®)
  • Ritonavir (Norvir®)
  • Clarithromycin (Biaxin®, Biaxin XL®)
  • Itraconazole (Sporanox®)
  • Ketoconazole (Nizoral®)
  • Nefazodone (Serzone®)
  • Saquinavir (Fortovase®, Invirase®)
  • Telithromycin (Ketek®) Inducers of CYP3A4
  • Efavirenz (Sustiva®)
  • Nevirapine (Viramune®)
  • Carbamazepine (Carbatrol®, Epitol®, Equetro™, Tegretol®, Tegretol-XR®)
  • Modafinil (Provigil®)
  • Phenobarbital (Luminal®)
  • Phenytoin (Dilantin®, Phenytek®)
  • Pioglitazone (Actos®)
  • Rifabutin (Mycobutin®)
  • Rifampin (Rifadin®)
  • St. John's wort

Exclusion Criteria:

Any of the following:

• Pregnant women
• Nursing women History of an allergic reaction to, or intolerance of, venlafaxine Treatment ≤ 7 days with other antidepressants, anticonvulsants, monoamine oxidase (MAO) inhibitors, or other neuropathic pain medication agents such as carbamazepine, phenytoin, valproic acid, gabapentin, lamotrigine, topical lidocaine patch or gel, capsaicin cream, or amifostine; in addition, they may not be taking other agents for the treatment of neuropathy, nor other known moderate or strong CYP 2D6 (which consist of Cinacalcet [Sensipar™], quinidine, and Terbinafine [Lamisil®, Lamisil AT®]), nor the strong inducer of CYP 2D6 terbinafine (Lamisil®, Lamisil AT®), nor the following drugs that substantially effect CYP 3A4 Moderate inhibitors of CYP3A4: > 2-fold increase in the plasma AUC values or 50-80% decrease in clearance
• Aprepitant (Emend®)
• Erythromycin (Erythrocin®, E.E.S. ®, Ery-Tab®, Eryc®, EryPed®, PCE®
• Fluconazole (Diflucan®)
• Grapefruit juice
• Verapamil (Calan®, Calan SR®, Covera-HS®, Isoptin SR®, Verelan®, Verelan PM®)
• Diltiazem (Cardizem®, Cardizem CD®, Cardizem LA®, Cardizem SR®, Cartia XT™, Dilacor XR®, Diltia XT®, Taztia XT™, Tiazac®) Other medical conditions which, in the opinion of the treating physician/allied health professional, would make this protocol unreasonably hazardous for the patient Prior neurotoxic chemotherapy Concurrent radiotherapy Current (within the last month) pre-existing peripheral neuropathy of any grade Uncontrolled hypertension (defined as 3 consecutive readings over the past year of over 160 systolic, and over 100 diastolic)