Low blood pressure occurs when blood pressure is much lower than normal. This means the heart, brain, and other parts of the body do not get enough blood. Normal blood pressure is usually between 90/60 mmHg and 130/80 mmHg. The medical name for low blood pressure is hypotension.
Symptoms of Low Blood Pressure
- Dizziness or lightheadedness
- Fainting (called syncope)
- Dehydration and unusual thirst
- Dehydration can sometimes cause blood pressure to drop. However, dehydration does not automatically signal low blood pressure. Fever, vomiting, severe diarrhea, overuse of diuretics and strenuous exercise can all lead to dehydration, a potentially serious condition in which your body loses more water than you take in. Even mild dehydration (a loss of as little as 1 percent to 2 percent of body weight), can cause weakness, dizziness and fatigue.
- Lack of concentration
- Blurred vision
- Cold, clammy, pale skin
- Rapid, shallow breathing
Heart problems… Some heart conditions that can lead to low blood pressure include extremely low heart rate (bradycardia), heart valve problems, heart attack and heart failure. These conditions may cause low blood pressure because they prevent your body from being able to circulate enough blood.
Endocrine problems …Thyroid disorders — such as parathyroid disease — adrenal insufficiency (Addison’s disease), low blood sugar (hypoglycemia) and, in some cases, diabetes can trigger low blood pressure.
Lack of nutrients in your diet… A lack of the vitamins B-12 and folate can cause a condition in which your body doesn’t produce enough red blood cells (anemia), causing low blood pressure.
Pregnancy… Because a woman’s circulatory system expands rapidly during pregnancy, blood pressure is likely to drop. This is normal, and blood pressure usually returns to your pre-pregnancy level after you’ve given birth.
Blood loss… Losing a lot of blood from a major injury or internal bleeding reduces the amount of blood in your body, leading to a severe drop in blood pressure.
Severe infection… (Septicemia). Septicemia can happen when an infection in the body enters the bloodstream. This condition can lead to a life-threatening drop in blood pressure called septic shock.
Severe allergic reaction… (Anaphylaxis). Anaphylaxis is a severe and potentially life-threatening allergic reaction. Common triggers of anaphylaxis include foods, certain medications, insect venoms and latex. Anaphylaxis can cause breathing problems, hives, itching, a swollen throat and a drop in blood pressure.
Medications that can cause low blood pressure…Some medications you may take can also cause low blood pressure, including:
- Diuretics (water pills), such as furosemide (Lasix) and hydrochlorothiazide (Microzide, Oretic)
- Alpha blockers, such as Prazosin (Minipress) and Labetalol
- Beta blockers, such as atenolol (Tenormin), propranolol (Inderal, Innopran XL, others) and Timolol
- Drugs for Parkinson’s disease, such as Pramipexole (Mirapex) or those containing Levodopa
- Certain types of antidepressants (Tricyclic Antidepressants), including doxepin (Silenor), Imipramine (Tofranil), Protriptyline (Vivactil) and Trimipramine (Surmontil)
- Sildenafil (Viagra) or Tadalafil (Cialis), particularly in combination with the heart medication, Nitroglycerin
Low blood pressure after eating (postprandial hypotension) – postprandial hypotension is a sudden drop in blood pressure after eating. It affects mostly older adults. Just as gravity pulls blood to your feet when you stand, a large amount of blood flows to your digestive tract after you eat. Ordinarily, your body counteracts this by increasing your heart rate and constricting certain blood vessels to help maintain normal blood pressure. But in some people these mechanisms fail, leading to dizziness, faintness and falls. Postprandial hypotension is more likely to affect people with high blood pressure or autonomic nervous system disorders such as Parkinson’s disease. Lowering the dose of blood pressure drugs and eating small, low-carbohydrate meals may help reduce symptoms.
Low blood pressure from faulty brain signals (neurally mediated hypotension) – this disorder causes blood pressure to drop after standing for long periods, leading to signs and symptoms such as dizziness, nausea and fainting. Neurally mediated hypotension mostly affects young people, and it seems to occur because of a miscommunication between the heart and the brain. When you stand for extended periods, your blood pressure falls as blood pools in your legs. Normally, your body then makes adjustments to normalize your blood pressure. But in people with neurally mediated hypotension, nerves in the heart’s left ventricle actually signal the brain that blood pressure is too high, rather than too low. As a result, the brain lessens the heart rate, decreasing blood pressure even further. This causes more blood to pool in the legs and less blood to reach the brain, leading to lightheadedness and fainting.
Adrenal Fatigue & Hypotension…The endocrine system is a group of specialized organs and body tissues whose primary functions are to produce, store and secrete hormones. Hormones are chemical messengers in the body; they transfer information and instructions from cell to cell. The hormones produced by the endocrine system have a great deal of influence over the body. The primary glands that make up the human endocrine system are the pituitary, parathyroid and adrenal glands. When the thyroid gland is not producing enough iodine and becomes imbalanced the effects can decrease blood pressure.
Hormones from the endocrine organs are secreted directly into the bloodstream, where special proteins bind to them to keep the hormones intact as they travel throughout the body. The proteins also act as a reservoir, allowing only a small fraction of the hormone circulating in the blood to affect the target tissue. Specialized proteins in the target tissue, called receptors, bind with the hormones in the bloodstream, producing chemical changes in response to the body’s needs.
Hypotension can have many causes as already stated. More research and evidence is pointing towards imbalances in the thyroid. When hypo-thyroid (lack of Iodine production) exists then the ability to produce and regulate hormones becomes incapacitated or diminished through the parathyroid gland that in turns effects the adrenals and prostate gland in men. Adrenal fatigue causes undue stress within the entire body systems. Hormones and the body’s chemical production slows or becomes diminished that effects the cardio vascular system and normal regulation of the heart and its electrical input and output. These are factors to consider when hypotension has been discovered. Many people have this condition their entire lives.
Not all hypotension is necessarily a negative factor. Many highly developed athletes have low blood pressure due to the efficiency of the body systems through very specific training regimes that also consider the diet as an essential key to performance and recovery after extreme duress. With today’s knowledge of electrolyte balancing, mineral utilization, thyroid regulation, and very specific diets design for normal function of the heart and blood pressure all of these areas must be considered and a complete evaluation of your condition is highly recommended.
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