It is not uncommon as we get older that our blood vessels continue to become stiffer, and as a result our blood pressure goes up, even if you are on medications. That being said, there are other causes for elevated blood pressure beyond old age. If this happens to be the first time your father s blood pressure is this high, and that this is unusual for him, sometimes the blood pressure can be falsely high from things as simple as a wrong sized blood pressure cuff, crossing your legs while getting your measurement, or even having your blood pressure measured on a full bladder, among other things. So next time he gets his blood pressure measured, make sure he is calm, that he has been sitting for at least 5 minutes, with an empty bladder and legs uncrossed. Other than having his blood pressure medication doses adjusted, if your father is particularly overweight or eats a lot of salty foods, aiming to reduce your salt intake and also losing as little as 10 pounds can cause your blood pressure to reduce in some instances. Foods especially to avoid include canned soups, pickles, chips, frozen dinners, sandwich meats, ramen noodles. Bottom line is, many things cause blood pressure to be high despite medications, but hopefully you will find these tips helpful.