Hi there, thanks for asking. There are a few natural substances which can help for depression and anxiety. St. John's Wort is a substance that is frequently used by people to treat mild to moderated depressions which are also some times accompanied with anxiety. It affect serotonin system in the brain and improves mood. Since it can affect the metabolism of many medications in the body, it should not be used with other medications before talking to your doctor.
Some people take ginseng for improving their mood and energy. It helps for better mood and energy, but it is recommended not to be taken more than 3 months since its effect will get weak.
It is good to see a doctor before using them to see if they are really needed to be taken.
Wish you a good health.

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