What causes a Sudden Drop in Blood Pressure?

By  , Expert Content
Jan 17, 2013

Sudden drop in blood pressure when you get up from lying down or sitting is known as postural hypotension, orthostatic hypotension, or neurally mediated orthostatic hypotension. Postural hypotension occurs due to failure of the autonomic nervous system.
Autonomic nervous system controls involuntary vital functions like heartbeat, blood pressure, and breathing.

When you, stand up from lying down or sitting, some blood pools in your lower limbs. But normally your body compensates for it increasing your heart rate and constricting the blood vessels. If this fails to happen, or occurs slowly, the blood pressure falls and postural hypotension results. Postural hypotension occurs more common in the elderly.


Cause of Postural Hypotension

Postural hypotension, or low blood pressure on standing up suddenly, can occur due to several reasons such as;

  • Dehydration or loss of water from body due to vomiting, diarrhea, or fever
  • Starvation or lack of food,
  • Standing for long period in the heat,
  • Excessive fatigue or tiredness
  • Elderly
  • Certain medications, like drugs to control high blood pressure (hypertension).
  • Dietary and psychological factors, and
  • Severe infection
  • Allergic reaction.
  • Pregnancy
  • Diabetes.
  • Dysfunction of autonomic nervous system

Some people can have hypotension after meals. It probably occurs due to pooling of blood into the vessels of the stomach and intestines.

Medications which can cause Postural Hypotension

Several drugs can cause postural hypotension. Medications that cause postural hypotension can be categorized as;

  • Drugs to treat high blood pressure: These include diuretics, beta-blockers, calcium-channel blockers, and angiotensin-converting enzyme (ACE) inhibitors.
  • Drugs with hypotension as a side effect: These include nitrates, drugs for Parkinson's disease, medications to treat erectile dysfunction, antipsychotics, neuroleptics, anti-anxiety agents, sedative-hypnotics, and tricyclic antidepressants.


Is it Helpful Article?YES2 Votes 13985 Views 2 Comments
I have read the Privacy Policy and the Terms and Conditions. I provide my consent for my data to be processed for the purposes as described and receive communications for service related information.
This website uses cookie or similar technologies, to enhance your browsing experience and provide personalised recommendations. By continuing to use our website, you agree to our Privacy Policy and Cookie Policy. OK