How much indian basil tea should you drink to relieve depression/anxiety?

Doesn't matter: There is no scientific evidence that indian basil tea is a treatment for depression. Depression is a serious medical disorder that should only be treated with interventions that have been shown to be effective in double blind placebo controlled studies.

Not sure: Not sure if there's a specific amount stated in any literature that can guide you how much to drink. My suggestion would be, whatever amount makes you feel better :-) but remember, anything in excess can also be bad for you.