After receiving information about sarcosine, the patient signed an informed consent form and started receiving the augmentation. Laboratory tests were performed (complete blood count, electrolytes, liver and renal parameters, lipids, prolactin and thyroid-stimulating hormone levels) which showed no deviations from the reference values. The patient had no neurological, endocrine, or other chronic comorbidities at the time of our treatment. On enrollment visit, we excluded changes in the treatment in the last 3 months, ongoing alcohol, and drug dependence or use in last 6 months. The patient was currently unemployed and on disability living allowance. Before adding sarcosine, olanzapine (25 mg per day) and venlafaxine (75 g per day) had been prescribed for several months without any significant mental state changes. Olanzapine was started over 3 years ago and venlafaxine a year ago due to depressive and negative symptoms.
