Blood pressure is the pressure exerted by the blood on the walls of the blood vessels (arteries). Medical science considers 120/80mmHg as normal blood pressure in adults.

Low blood pressure, otherwise known as hypotension, occurs when the blood pressure decreases to 90/60mmHg or lower. While, for some people, hypotension does not create any significant problems, for others, it can cause dizziness or fainting spells.

Low blood pressure is not a disease itself but a sign of other medical conditions. It can be easily managed or prevented by finding the underlying cause and treating it.

Symptoms of hypotension

The symptoms of low blood pressure could be mild, moderate or serious, depending on the cause. Following are some of the symptoms you may notice:

• Dizziness or lightheadedness
• Nausea
• Syncope (fainting)
• Lack of concentration
• Blurry vision
• Fatigue or weakness
• Dehydration or feeling thirsty

In an extreme case, hypotension can become life-threatening. In such situations, you may note:

• Rapid, shallow breathing
• Cold, clammy and pale skin
• Weak and rapid pulse
• Confusion

This serious condition usually occurs due to sudden shocks such as blood loss due to trauma, internal bleeding or anaphylaxis (severe allergic reaction). It becomes difficult for blood to reach the organs, leading to a drop in the blood pressure.

Some of the underlying conditions that may lead to hypotension are

1. Pregnancy: The blood pressure commonly drops during the first 24 weeks of pregnancy; however, it usually returns to normal after delivery.
2. Heart problems: Heart conditions such as low heart rate, heart attack and heart valve disease can cause hypotension.
3. Dehydration: Loss of fluid that occurs due to diarrhea, fever, vomiting and long workout sessions might cause your blood pressure to plummet.
4. Certain medical conditions: Parathyroid disease, Addison's disease, low blood sugar (hypoglycemia) and diabetes may lead to hypotension.
5. Nutrition deficiency: A deficiency of nutrients like vitamin B, folate and iron can lead to anemia. Anemic people can suffer from hypotension
6. Medication: Some medications can also cause a drop in blood pressure. These include antihypertensives, antidepressants, Parkinson's disease medication and certain heart medications.

Types of low blood pressure

Following are some types of hypotension:

1. Orthostatic hypotension

The transition from sitting or lying down to standing up leads to a brief drop in blood pressure. As the body adjusts to the position change, you may feel dizzy for a brief moment.

2. Neurally mediated hypotension

Neurally mediated hypotension mostly occurs due to standing for a long period of time and is more commonly seen in children than adults. Sudden emotional or sad events can also cause hypotension.

3. Postprandial hypotension

Postprandial hypotension refers to a drop in blood pressure that occurs right after eating.

Treatment and tips for low blood pressure

• The treatment depends on the underlying cause of hypotension. Medicinal treatment could include medications for heart disease, diabetes, diarrhea, etc.
• Consult your doctor for a change or alteration in your medication or dose if the hypotension is caused by your ongoing treatment.
• Stay hydrated to treat and prevent the symptoms of neurally mediated hypotension.
• Avoid standing for long hours or take a break to sit down often. Also, avoid standing up immediately after eating.
• Try to reduce your stress levels to avoid emotional trauma.
• Prevent orthostatic hypotension by slow and gradual movements. Avoid swift transitions in your position and cross your legs while sitting.
• Speak to your doctor about whether you need to increase your salt intake.
• Shock-induced hypotension needs emergency medical interventions such as fluid or blood transfusion and so you must seek emergency medical help.

For more information, read our article on Low Blood Pressure.