Patient description: A 46-year-old Asian woman with MDD complains of persistent feelings of sadness and loss of interest in daily activities. She states that her mood is still depressed most of the days. She complains of loss of energy and feelings of worthlessness nearly every day. She is on anti-depressants for the past 6 months, but the symptoms are still present. She does not drink alcohol or smoke. She used to exercise every day for at least 30 min., but she doesn't have enough energy to do so for the past 3 weeks. She also has some digestive issues recently. She is married and has 4 children. She is menopausal. Her husband was diagnosed with colon cancer a year ago and is undergoing chemotherapy. Her past medical history is unremarkable. Her family history is negative for any psychologic problems. Her HAM-D score is 20.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  To Determine the Bioavailability of Tranylcypromine Subjects will be normal, healthy adult men and women who volunteer to participate Is the individual healthy, nonsmoking, normal adult man or woman who volunteers to participate? Is s/he at least 18 years of age? Is his/her BMI between 19 and 30, exclusive? Is she willing to avoid pregnancy by abstaining from sexual intercourse, or by the use of barrier methods. (diaphragm, condom, foams/jellies, sponge), and IUD, or has she has been surgically sterile or post menopausal at least six months prior to entering into the study? Is s/he considered reliable and capable of understanding his/her responsibility and role in the study? Has/s/he provided written informed consent? A no answer to any of the above questions indicates taht the individual is ineligible for enrollment  Does the individual have a history of allergy or hypersensitivity to tranylcypromine? Does/ s/he have clinically significant laboratory abnormalities that would interface with the conduct or interpretation of the study or jeopardize his/her safety? Does s/he have significant history or clinical evidence of auto-immune, cardiovascular, gastrointestinal, hematopoietic, hepatic, neurological, ongoing infection, pancreatic, or renal diseases that would interface with the conduct or interpretation of the study or jeopardize his/her safety? Is she nursing? Does s/he have serious psychological illness? Does s/he have significant history ( within the past year) or clinical evidence of alcohol or drug abuse? Does s/he have a positive urine drug screen or saliva alcohol screen, or a positive HIV-1 , or hepatitis B or C screen, or a positive pregnancy test?-Is s/he unable to refrain from the use of alcohol or xanthine-containing foods or beverages during periods beginning 48 hours prior to study drug administration and ending when the alst blood sample has been taken? Is s/he unable to refrain from the ingestion of smoked meat, cheese (except cream cheese and cottage cheese), wine and beer during periods beginning 48 hours prior to study initiation and ending seven days after the last blood sample has been taken in study period two? Has s/he used any prescription drug during the 14-day period prior to study initiation, or any OTC drug during the 72-hour period preceding study initiation? Is s/he unable to refrain from the use of all concomitant medications during the study?