99% of homeopathic remedies are a waste of money and can potentially do harm(through drug-drug interactions)
St John Wort may help mild depression, but recent studies showed no effect. At high doses it actually has more side effects than SSRI's
Kava used to be used for anxiety...but found to cause liver damage if used chronically
Ecinacea is one of the biggest sellers, but never proven to be effective.