I may be telling people to 'suck eggs' here as you probably already know, or rain on anybody's parade; but here it goes anyway for anybody reading that doesn't.

R.E: St John's Wort.
I have seen 'vivid dreams' listed as a side effect. Others inc. some people may experience sensitivity to sunlight. Sexual/erectile dysfunction, etc. People suffering from Alzheimer’s disease, bipolar disorder, schizophrenia may find their symptoms worsen.
Do NOT use with antidepressants, particularly SSRIs due to increase risk of serotonin syndrome.