Why Does Blood Pressure Drop?

Hypotension, or low blood pressure, is when the blood pressure in your arteries is abnormally low. If your blood pressure goes too low, it may limit the amount of blood flow getting to your brain and other organs that are vital, causing dizziness, unsteadiness or fainting. You should see your doctor right away if you experience any symptoms of low blood pressure and are worried.

Everyone should have their blood pressure checked every five years at least. If you don’t know what yours is or haven’t had it checked, ask your doctor to do so for you.

What is Low Blood Pressure?Postural Hypotension

A constant supply of blood is pumped around your body by your heart through veins, arteries and capillaries. Blood pressure is the strength of the blood on the artery walls as the blood flows in them. It is recorded in two measurements, systolic pressure and diastolic pressure. Systolic is the pressure as your heart is beating and squeezing blood into the arteries, while diastolic is the pressure while your heart is resting between beats.

Typical blood pressure sits between 90/60 and 140/90. If your blood pressure comes in less than 90/60, your blood pressure is considered to be low.

Low blood pressure can occur for many reasons, and can do with your age, the time of day, any medications you’re on, the temperature, some illnesses and injuries. It is normal for your blood pressure to vary throughout the day, depending upon what you are doing. If your blood pressure reading is low, your doctor will check first to see if it is affected by any of these factors:

  • The time of day – overnight, your blood pressure will naturally be lower when you sleep and rise a few hours before you wake up, continuing to rise throughout the day, getting to its highest point by mid-afternoon.
  • How relaxed or stressed you are – when you are relaxed, your blood pressure will be lower.
  • How much exercise you do – exercise will initially raise your blood pressure, however if you are healthy and regularly exercise, your blood pressure will return to low while resting.
  • Temperature – a temperature that is warm can cause your blood pressure to fall.
  • If you’ve eaten recently- when food needs to be digested, food is sent to the gut, so blood pressure in other parts of your body will fall.

If after considering these factors your blood pressure is still low, there could be another cause. Some possibilities include:

  • Genes – some research has said low blood pressure is genetics. It is possible for you to inherit from your parents if they have low blood pressure as well.
  • Age – normally your blood pressure will increase as you get older, but a drop from eating or movement is more common with age.
  • Medicationsome kinds of medication can cause low blood pressure.

Self-help and Treatment


Blood pressure which is naturally low won’t likely need to be treated unless it causes recurrent falls and dizziness. Your doctor should then look at what is causing it and how it can be treated. There are several things you can do to help limit symptoms, which include:

  1. Standing slowly and not standing for long periods of time
  2. Keeping well hydrated
  3. Adding additional salt to your diet
  4. Eating smaller, more frequent meals