What’s the difference between high blood pressure and low blood pressure? 3 things to know

I often receive email messages from wives frustrated with their husbands who refuse to take better care of their health. 

A popular issue is the spouse’s refusal to take prescribed medications for conditions like high blood pressure. At times the problem may be that they simply don’t want to be bothered or don’t want to admit they have a problem. Typical male behavior, of course, and I’m as guilty as the next guy (just ask my wife). But oftentimes the problem is unpleasant side effects, a problem for both husbands and wives.

It’s easy to rationalize and quit taking meds, especially when it comes to blood pressure. This is because when blood pressure is high, and even when it’s very high, there typically are no symptoms. That’s why it is referred to as the silent killer. No symptoms are interpreted as meaning no problem, and if there is no problem, why bother taking meds, especially if there are unpleasant side effects?

Unfortunately, this interpretation is very wrong and dangerous, but all too common. So, is there an effective strategy to apply to this problem? Here’s what to know about high blood pressure.

What is blood pressure and how does the body regulate it?

The body places a high priority on regulating all systems, especially blood pressure, but it’s a major challenge because several factors are involved and each can be influenced in a variety of ways. This means there are lots of things that can go wrong without you knowing it.

In simplistic terms, blood pressure involves a cooperative effort by three components, and each component is carefully controlled by specific nerves and hormones. The three components are a pump (the heart), tubes (the blood vessels), and fluid in the tubes (the blood), and these are maintained in a delicate balance. For example, if the pump is too strong or pumps too often, blood pressure goes up, and the same is true if the vessels constrict (narrow) too much, or if there is too much fluid volume in the vessels.

Because control of blood pressure involves a highly complex system that can go haywire in a number of ways with many possible causes, it’s not easy to find a workable solution when the pressure is too high. In turn, there may be a need for patience and a bit of trial and error to find the best treatment and reach the desired “Goldilocks” level, not too high and not too low.

How do you pick the correct high blood pressure medication?

When choosing a medication to treat high blood pressure, the doctor is confronted with a variety of choices. There are medications that cause the heart to beat less often and contract less forcefully. There also are medications to reduce fluid volume, and others that relax the vessels, dilating them to allow blood to flow more easily. In addition, decisions must be made about the strength of dosage. All of this points to the need to enter into a partnership with your doctor which requires quick and accurate feedback from you, the patient, to help the doctor make the best choices and changes as needed.

Unfortunately, the more common approach is to get a prescription, take the medication, and if there are side effects, quit taking it. Worse, don’t tell your doctor you quit, or don’t be truthful, which can lead your doctor down a blind alley.

Above all, if meds are prescribed, it is serious business, and one way or another a solution must be found. If not, refusing to take blood pressure meds because of side effects makes about as much sense as going to a clothing store to buy a pair of pants, trying on a pair that doesn’t fit, and concluding that you will go without pants.

High blood pressure imposes a serious health risk even though there may be no symptoms. At the same time, there must also be an appreciation for the complexities surrounding the regulation of blood pressure. This means effective treatment requires working hand in hand as partners with your doctor to find the right medication and dosage that gets the job done, and without unpleasant side effects.

What causes low blood pressure?

Although it’s true that, in general, the lower the blood pressure the better, if it gets too low it creates problems like dizziness and fainting, and 90/60 mmHg is a low-end guideline. Thankfully, low blood pressure is much less common than high blood pressure but managing it can still be a challenge and require medications. An example is a medication that constricts blood vessels to increase pressure.

When it comes to treatment, it’s important to make the distinction between chronic low blood pressure that requires medication versus transient low pressure caused by circumstances. For example, the circumstance of bending over then rising quickly can cause a sudden drop in blood pressure which is more common in the elderly. Why? The system doesn’t work as well or as quickly as it should. Here’s why.

The body is programmed to be on guard to ensure that blood flow to the brain is never interrupted. The protective system begins with receptors located in the carotid arteries that feed the brain, and their job is to constantly monitor pressure. This system works so well that we take it for granted until we bend down and rise quickly. With the head down it’s easier to transport blood to the brain which allows the cardiovascular system to relax a bit. Then, if you stand abruptly, the system has to make an instantaneous adjustment to increase blood flow. With advancing age, the system doesn’t respond as quickly, causing dizziness and possible fainting. Dehydration which reduces blood volume also can be at fault, a common problem in the elderly, and the cure is to drink more and rehydrate.

Reach Bryant Stamford, a professor of kinesiology and integrative physiology at Hanover College, at [email protected].