My advice is get all the documentation from your primary physician, know the regs for what is and is not allowable medication. Here is an unofficial list from a company that specializes in medical certification for pilots:

http://www.leftseat.com/medcat1.htm

but absolutely under NO circumstances should you do either of the following:

1) lie on the medical forms
2) Go in and "consult" with your AME before the medical. The rules have changed (cira 2005) and anything said in the "consult" is grounds for not issuing the medical when you take the exam.. In other words, simply talking to the AME about a disqualifying condition can lead to a denial of medical certification.

The FAA will usually defer to Oklahoma City and request more documentation… Its better to have all this on the front end before they ask for it. It will also help to have a letter from your Dr telling them what your exact condition is, how its managed, how well you are responding to the treatment and that in his option you are not a risk to the safety of flight.

As you can tell, I’ve been thru the special issuance thing before
References :
Flight Instructor

Should you develop it later on (and it’s not a certainty that you will) and can manage it, still not a problem. You’ll need to have it taken care of and documented properly but it isn’t a permanent disqualification. There are plenty of pilots out there on blood pressure meds.
References :

I don’t know much about the medical side, I’m sorry I can’t be of more help but I do recommend a physical before a medical if you have even the slightest thought that you may have some issues.
References :

http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr&sid=3097f0aa3bf12c8f874b6280bc314e02&rgn=div5&view=text&node=14:2.0.1.1.5&idno=14
References :