Lactobacillus Helveticus in the Treatment of Major Depression

Double-blind Placebo-controlled Clinical Trial of Lactobacillus Helveticus as an add-on Strategy for the Treatment of Major Depression

The main objective of the study is to evaluate whether the association of the probiotic Lactobacillus helveticus to standard antidepressant will contribute to the treatment of major depression.

Patients with the diagnosis of major depression according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria will receive one daily oral dose of 1 × 10^9 colony-forming units (CFUs) of Lactobacillus helveticus or placebo for 8 weeks in addition to conventional antidepressant treatment.

Inclusion Criteria:

• Aged between 18 and 65 years old;
• Diagnosis of major depression
• Agree to sign the informed consent.

Exclusion Criteria:

• Treatment with anti-inflammatory drugs or antibiotics of any pharmacological classes in the month before treatment enrollment;
• Use of dietary supplementation (herbal supplements, other pro- or prebiotics).