St.John's Wort...
what do YOU use it for, internally?

Does it have any side effects?

What meds does it counteract?

I just started taking it for anxiety and mild depression. It takes 4-6 weeks to start working for that.
The main side effect is photosensitivity. You really need to be more careful in the sun. Some people (especially those w/ other flowering plant allergies) can have allergic reactions like rashes.
As for drug interactions it can decrease the effectiveness of birth control pills.
There are some recent studies that talk about the different parts of St. John's Wort and their effectiveness for depression. Currently, most types contain standardized hypericum but they are thinking that the hyperiform element of the plant might be more beneficial. I decided to take one that is standardized for the hypericum but also contains whole plant so you get hyperiform too. The main reason for taking one that is standardized is that they blend it all together and measure it so that the hypericum is in the same dosage in each pill/dose. Supposedly it is more reliable that way.
I have an appointment with an herbalist I know in a few weeks and she is very knowledgable. I am curious to get her take on it.

The main side effect is photosensitivity. You really need to be more careful in the sun.

I want to share this. Many herbalists use ST JOHNS WORT OIL as sun protection.

Bubbles is right, it is said that St j's can cause photosensitivity, but there are so many practicing herbalsts that prove that wrong. I am not certain it is fact or if it is, it is in a small few.

St J's is used often for depression, of course as she said above.
Also though it is good for muscle relaxing. I used it in oil form during labor and delivery.
It helps restore damaged nerve tissue and also deadens nerve pain. It also stregthens urinary organs. good also for athletic injuries such as pulled muscles adn ligaments.
The botanical name is hypericum perforatum. Hyreicum translates "over an apparition"
:D

The oil stains though so I am warning you if you buy oil and use externally. I ruined a few things.

skullcap is really great too...