If you can't reach your doctor, check with your pharmacist. They have drug interaction medication information handy. I googled Prozac for drug interactions and here's what I found. "Until more is known about interactions and adverse actions, people taking any SSRI drugs, including fluoxetine, should avoid St. John’s wort, unless they are being closely monitored by a doctor."
I agree with the recommendation to steer clear (at least until you talk to your doctor).
Just my opinion, I am not medically trained, but very careful when it comes to taking anything. I take thyroid hormone and have to watch taking anything within 4 hours, even eating grapefruit.
Hope this helps