I've not tried a SAD lamp but I have tried St John's wort. The dosages vary depending on what brand you buy so it's not recommended by doctors in the UK. I didn't have any side effects with it, but neither did it help my depression. I don't know if you're on any other meds but SJW interacts with LOADS e.g. contraceptive pill, blood pressure pills, anti-depressants, triptans (used for migraines) etc etc. Be careful

*Willow*