Yes, St. John's Wort has an extensive list, over 700 medications, that it can interact with in a negative way. This list is so long, that countries such as France have outlawed this herbal remedy. Other countries are taking steps to educate the public about these interacts, and to use St. John's Wort with caution. You can find drug interaction search engines on the Net, and also check with your pharmacist/chemist, as they are the experts in this area.
St. John's Wort has been shown to be effective for some individuals with mild to moderate forms of anxiety, but has not been proven to work well with more severe forms of anxiety disorder such as panic disorder/panic attacks.
As Cuch mentioned to you, it can work for some people, and others experience no benefit at all. Still, it might be worth a try, just watch out of those interactions.
The very best to you, Chuck!... Chuck