Presumably, you are hypertensive (High Blood pressure) and have been prescribed a prescription medication to control the blood pressure.
As much as I don't like taking prescription drugs, the advantage of them is that they are targeted to deal with a particular aspect of bringing down your blood pressure. There are several common classes ...
Vasodilators which incude ACE Inhibitors, Angiotensin II receptor blockers.
Then there are the drugs that control the effort your heart puts into each beat ... these include the Calcium channel blockers and Betablockers.
They work remarkably well with few side effects when the dose is right and aren't subject to the whims of your dietary habits. (Like the green tea you bought today has far fewer flavonoids than the one you bought last week and so doesn't work anything like as well)
Probably the important thing to consider is the things that promote higher blood pressure ...
Avoid stimulants for they will raise your blood pressure They often act as a vasoconstrictor ... just the opposite of what you need!
caffeine (limit your coffee intake ... a mug or two a day is OK, several big gulps are likely to cause you problems!)
nicotine (if you're a smoker, the biggest favour you can do for your heart is to stop)
decongestants (if you suffer from allergies and take meds like sudafed or combination drugs that contain an antihistamine and a decongestant ... the two common ones are pseudoephedrine and phenylephrin ... and also decongestant nasal sprays)
Avoid excess sodium (salt) ... 1 tsp per day (2400mg = approx 5 ml) and that can come from salt or sodium bicarb too ... as you'll find in pancakes, and cakes and cookies. Also watch your potassium intake.
Then there's the dreaded fats and cholesterol. There is a myth that says you must avoid dietary cholesterol at all costs (leading to the "Contains zero Cholesterol" claims by food makers). The reality is that most of the body's cholesterol comes from our own liver's production, and not our diet. What happens is that the fats we consume, particularly saturated and worse, transfats, scoop cholesterol out of the liver and deposit it around the body, and so the liver tries to make MORE cholesterol for all the stuff the fats are carrying around our blood!
So, the thing to do is to cut down the fat in your diet to levels of under 60 gm total fat per day and make that of as little saturated fats as you can (from meats) and most important zero transfats.
Exercise is good for helping lower your resting bp. Not heavy amounts, or "no pain no gain exercise" ... 30 minutes good brisk walking 5 days a week will help a lot. It also will increase the production of the body's HDL cholesterol, which is a scavenger for LDL cholesterol ... not just the stuff in the blood, but also scavenges stuff that's already on the inside of the arteries ... helping to reduce the atherosclerosis making the arteries more flexible and thus reducing BP.
TO take you back to your original question, there are some pointers here for natural ways to help. If you've been told you have high BP though, I think medications are definitely going to ensure that it is more effectively controlled. If you are a smoker, and/or drink lots of coffee or colas etc. and/or love salty foods, then if you can alter your diet, maybe the reduction or elimination of the meds can be achieved once you've evolved to a new lifestyle. The good thing about the meds is that your BP is down within hours cutting your risks of heart attack and stroke almost instantly.
http://www.healthcastle.com/high-cholesterol-
diet.shtml 
