Amino acids are a safe, effective way to alleviate depression, anxiety and other mental health issues.
I recommend the book The Mood Cure by Julia Ross as an excellent place to start your research on amino acids to boost mental health. It has a quiz at the beginning of the book that will help you to identify which amino acids might be best for your symptoms. It goes into detail about how much to take, when to take them, and some of the other root causes of depression and anxiety such as thyroid or adrenal issues.
Here is a quick chart to illustrate some natural amino acid alternatives to common psychiatric medications: