1. Able to provide informed consent.
2. Not pregnant
3. Willing to participate in follow up as part of the study
4. Diagnosis of MDD and/or GAD by MINI
5. Current depressive episode with a MADRS score of â‰¥15 or Current GAD episode with GAD-7
score of â‰¥8.
6. Able to understand and comply with the requirements of the study
7. Able to provide stool and blood samples.
1. History of chronic diarrhea
2. Need for regular use of agents that affect GI motility (narcotics such as codeine or
morphine, agents such as loperamide or metoclopramide)
4. Elective surgery that will require preoperative antibiotics planned within 6 months of
5. Pregnant, breastfeeding, or planning to get pregnant in the next 6 months
6. Any condition for which, in the opinion of the investigator, the participant should be
excluded from the study.
7. Current use of any antidepressant/antianxiety drug (eligible to participate after a
4-week washout period)
8. Use of any antibiotic drug in the past 4 weeks (may be eligible to participate after a
1-month washout period)
9. History of alcohol or substance dependence in the past 6 months
10. Daily use of probiotic product in the past 2 weeks (may be eligible to participate
after a 2-week washout period)
11. Use of any type of laxative in the last 2 weeks.
12. Consumption of products fortified in probiotics
13. High suicidal risk, as measured by MADRS item 10 score more than 3 (or 4)
14. Current psychotic symptoms
15. Bipolar Depression
16. History of epilepsy or uncontrolled seizures
17. Immunodeficiency (immuno-compromised and immuno-suppressed participants; e.g. acquired
immune deficiency syndrome [AIDS], lymphoma, participants undergoing long-term
corticosteroid treatment, chemotherapy and allograft participants)
18. Unstable medical conditions or serious diseases/conditions (e.g. cancer,
cardiovascular, renal, lung, diabetes, psychiatric illness, bleeding disorders, etc.)
19. The use of natural health products (Natural health products [NHPs]; e.g. St. John's
Wort, passion flower, etc.) that affect depression
20. History of Electroconvulsive therapy (ECT)