If you take alpha-blockers (such as doxazosin or tamsulosin), you should wait at least 6 hours between taking those and taking Spedra. You will be unsuitable for Spedra if you are taking nicorandil or nitrates, such as GTN spray or isosorbide mononitrate tablets to treat angina.
Recreational drugs react dangerously with Spedra. It is important that you let us know which prescription, over-the-counter medicines and recreational drugs you are taking so that we can prescribe Spedra safely.