1. Use of any antidepressant drug

2. Use of any antibiotic drug in the past 4 weeks (may be eligible to participate after a 1-month washout period)

3. Use of any sleep medication in the past 4 weeks (may be eligible to participate after a 1-month washout period)

4. Milk, yeast, or soy allergy

5. History of alcohol or substance abuse in the past 6 months

6. Daily use of probiotic product in the past 2 weeks (may be eligible to participate after a 2-week washout period)

7. Use of any type of laxative

8. Consumption of products fortified in probiotics

9. Severely suicidal

10. Experiencing psychosis or bipolar episode

11. History of epilepsy or uncontrolled seizures

The Efficacy, Safety, and Tolerability of Probiotics on the Mood and Cognition of Depressed Patients