Low Blood Pressure (Hypotension)

We hear a lot about high blood pressure, but not as much about low blood pressure. Dr Joe Kosterich talks about low blood pressure, including who gets it, what happens, types of low blood pressure, what causes it, and what you can do about it.

We don’t hear a lot about low blood pressure and there are probably a couple of reasons for that. The first one is that it’s not a defined disease or condition like high blood pressure and the other, is that it’s not anywhere near as prevalent and treatments are a little more hit-and-miss.

When we’re talking about blood pressure, like with everything to do with the body, there is a normal range. Different people will have different, if you like, normal blood pressures and these will be a function of size and also of age. For example, a thinly built 18-year-old lady will be expected to have a different blood pressure to perhaps an overweight 60-year-old man. So there is that normal and reference range. As people get older, one would expect that the blood pressure will increase slightly because the heart has to work a little bit harder to pump the blood through the arteries.

When we’re talking about low blood pressure, what are the sorts of things you might experience? The hallmark symptom is dizziness. People feel faint – sometimes to the point of actually needing to hold onto something to stop falling over or literally fainting. Some people may feel a little bit nauseated and occasionally people may get a headache; others may feel a little light-headed without actually feeling faint. Obviously these are relatively nonspecific symptoms and can be caused by other things, so ultimately the only way you know what your blood pressure is doing is by having it checked. You can go and see your doctor to do that, but some people these days have monitors at home that they can use.

There’s another type of low blood pressure caused by a postural drop in blood pressure when people go from lying to sitting, from sitting to standing or from lying to standing. The reflexes that control your blood pressure can be a little bit slower as we get older and people may feel faint when they first get out of bed in the morning.

The next step becomes, what can we actually do about it? First and foremost, it’s important to rule out simple things like low blood pressure being a side-effect of medications and the most obvious side-effect of a medication that it could be is a tablet for high blood pressure. If you’re on high blood pressure medication and you’re feeling faint, it may be that your blood pressure has dropped too low. There are some other medications that can cause low blood pressure as a side-effect and that would obviously be something to talk about with your doctor. If you’re dehydrated that will also cause drops in blood pressure so particularly in the summer months, it’s important that you keep adequately hydrated because you’re more likely to faint and your blood pressure drops if you’re low on water.

For some people there is no known cause. For others, it may be related to some hormone disturbances, for example problems with the thyroid gland or with the adrenal gland and often you may have other symptoms if that is the case.

Assuming you’ve been through this process and the causes – which are hopefully simple ones – have been found, what do you do then? If people have genuine, what’s called, orthostatic hypotension, or the one that’s related to posture, then the simple thing is making sure that you get up slowly to allow the body to adjust. If, when you’re 20, you can leap out of bed and the reflexes move almost instantaneously, when you’re 70 they may not move quite as quickly. This means that when you’re going from lying to sitting, sit on the edge of the bed for maybe 30 seconds, get yourself used to it, then stand for maybe 30 seconds and walk off. This allows the body to catch up.

For some people, if they’re getting low blood pressure during the day, the compression stockings can be helpful. They’re not a cure as such, but they can be helpful. They squeeze a little bit more blood into the circulation. There is a medication, or a couple of medications, that can be used but they’re used fairly rarely and that can be something to talk about with your doctor.

To sum up, low blood pressure will most commonly present as feeling a little bit light headed or dizzy. The most common reason would be that you haven’t had enough water to drink so that’s something to check. It may be related to some medications you’re taking. It certainly is important to get your blood pressure checked and have a little bit of a chat with your doctor. It’s most likely to be a simple cause and a relatively simple solution. There may be some practical things you can do and in the more rare instances, other things may need to be done.