Inclusion Criteria:  Newly diagnosed MDD patients by DSM-5 criteria at the outpatient department of Psychiatry, BSMMU Moderate and severe MDD according to DASS-21 (scores from 14-27) Prescribed only SSRIs Age: 18 or older Gender: both male and female  Exclusion Criteria:  Patients having any psychiatric disease, kidney disease, myasthenia gravis, or gastrointestinal disease Taking dietary supplements in the last two months Taking fluoroquinolones, aminoglycosides, tetracyclines, calcium channel blockers, bisphosphonates, and skeletal muscle relaxants Pregnancy and lactation