Low Blood Pressure

Low Blood Pressure symptoms, causes, treatment options available in Australia, and when to see a doctor. Evidence-based medical information.

Dr. Louis J Sisk

BSc(Hons) MBChB MRCS(Glasg) MTrauma

Published: August 23, 2025

Overview

Low blood pressure, or hypotension, is a condition characterised by blood pressure readings lower than the normal range, typically defined as a systolic blood pressure less than 90 mmHg or a diastolic pressure less than 60 mmHg.

How it works in your body (pathophysiology):

Low blood pressure, also known as hypotension, affects your body through specific processes:

Blood pressure readings: It is when your blood pressure is lower than normal. This means a systolic pressure (pressure when the heart beats) less than 90 mmHg or a diastolic pressure (pressure when the heart rests) less than 60 mmHg.
Inadequate blood flow: Your organs might not get enough blood. This can happen due to:
- Decreased cardiac output: Your heart pumps less blood than usual.
- Reduced blood volume: There is less blood in your body.
- Excessive vasodilation: Your blood vessels widen too much.

Statistics and Prevalence in Australia

Current Australian health statistics do not specifically report the prevalence of low blood pressure.

The Australian Institute of Health and Welfare (AIHW) and the Australian Bureau of Statistics (ABS) have concentrated their efforts on hypertension, affecting approximately 34% of adults, equating to about 6.8 million people [1][3]. This focus reflects the significant health burden posed by high blood pressure, which remains a leading cause of morbidity and mortality in Australia [2][3].

Symptoms and Clinical Presentation

The clinical presentation of hypotension can vary widely. Early symptoms may include dizziness, light-headedness, blurred vision, and fatigue. More severe manifestations can involve syncope (fainting), confusion, and shock, which require immediate medical attention.

Red flag symptoms, such as chest pain, severe headache, or difficulty breathing, necessitate urgent evaluation [4][5].

Atypical presentations may occur in different populations, such as the elderly, who might experience falls or cognitive impairment due to hypotension. Additionally, individuals with chronic conditions like diabetes or Parkinson's disease may exhibit unique symptom patterns [5].

Causes and Risk Factors

Hypotension can result from various causes, including dehydration, heart problems (such as bradycardia or heart failure), endocrine disorders (like adrenal insufficiency), severe infection (sepsis), and blood loss. Medications, including diuretics, beta-blockers, and antidepressants, can also induce low blood pressure. Risk factors include age, prolonged bed rest, pregnancy, and certain medical conditions [6][7].

The pathophysiological mechanisms involve complex interactions between the cardiovascular and nervous systems, where disruptions can lead to inadequate blood flow and pressure regulation [6].

Diagnosis

Diagnosing hypotension involves a comprehensive clinical assessment, including a detailed medical history and physical examination. Blood pressure measurement is fundamental, and orthostatic blood pressure readings (measured when lying down and standing) can help identify orthostatic hypotension. Laboratory tests may include blood counts, electrolytes, and kidney function tests to identify underlying causes. Imaging studies, such as echocardiograms, can assess cardiac function if heart disease is suspected [5][7].

Australian guidelines do not provide specific protocols for hypotension, but general cardiovascular assessment guidelines from the RACGP and NHMRC are applicable [5][6].

Treatment Options in Australia

Treatment for low blood pressure in Australia is guided by the underlying cause and the presence of symptoms. Asymptomatic hypotension typically does not require intervention. For symptomatic cases, treatment options include increasing fluid and salt intake, wearing compression stockings, and adjusting or discontinuing medications that may contribute to low blood pressure. Pharmacological treatments, such as fludrocortisone or midodrine, may be considered in persistent cases [6][7].

The Medicare Benefits Schedule and Pharmaceutical Benefits Scheme provide support for diagnostic tests and medications, ensuring accessible care for Australians [6].

Living with Low Blood Pressure

Managing low blood pressure involves regular monitoring and lifestyle modifications. Patients are advised to rise slowly from sitting or lying positions, stay hydrated, and avoid alcohol. Dietary adjustments, such as increased salt intake, may be recommended under medical supervision. Regular follow-up with healthcare providers is crucial to monitor symptoms and adjust treatment as needed [6][7].

Patient education is vital, empowering individuals to recognise symptoms and seek timely medical advice. Psychosocial support and care coordination are also important, particularly for those with chronic conditions or complex health needs [6].

Prevention

Preventing hypotension involves addressing modifiable risk factors. Strategies include maintaining adequate hydration, avoiding prolonged standing, and managing chronic health conditions effectively. Regular health check-ups can help identify potential issues early, allowing for prompt intervention [6][7].

You might also be interested in:

High Blood Pressure - Understanding hypertension causes, symptoms, and management
Heart Attack - Recognising heart attack symptoms and emergency response
Chest Pain - Understanding chest pain causes and when to seek help
Heart Failure - Managing heart failure symptoms and treatment options