Blood pressure is an important indicator of adrenal health and function. Mild adrenal weakness is usually accompanied by normal to high blood pressure. As Adrenal Fatigue advances, low blood pressure, at rest or related to posture becomes more prevalent. This paper will attempt to examine how a weak adrenal can drastically alter the blood pressure landscape in the body. In particular, we will examine the physiology behind low blood pressure within a setting of advanced Adrenal Fatigue and the wide variety of symptoms such as dizziness, lightheadedness, orthostatic hypotension and heart palpitations that accompany this state.
Blood Pressure Basics
Blood pressure is the force exerted by circulating blood on the walls of blood vessels. It constitutes one of the key vital signs of life, along with heartbeat, rate of breathing, and temperature. Blood pressure is generated by the heart pumping blood into the arteries and is regulated by the response of the arteries to the flow of blood.
A person’s blood pressure is expressed as systolic/diastolic blood pressure, for example, 120/80. The systolic blood pressure (the top number) represents the pressure in the arteries as the muscle of the heart contracts and pumps blood into them. The diastolic blood pressure (the bottom number) represents the pressure in the arteries as the muscle of the heart relaxes after it contracts. Blood pressure is always higher when the heart is pumping (squeezing) than when it is relaxing.
Systolic blood pressure for most healthy adults falls between 90 and 120 millimeters of mercury (mm Hg). Diastolic blood pressure falls between 60 and 80 mm Hg. The common accepted guidelines define normal blood pressure as lower than 120/80. Blood pressures over 130/80 are considered high.
Unlike high blood pressure, low blood pressure is defined primarily by signs and symptoms of low blood flow and not by a specific blood pressure number. Low blood pressure is not defined by blood pressure readings below a certain threshold. Vegetarians, for example, generally have low blood pressure and at the same time are quite healthy and asymptomatic. Some individuals may have a blood pressure of 90/50 with no symptoms of low blood pressure and therefore do not have low blood pressure clinically. However, others who normally have high blood pressure may develop symptoms of low blood pressure if their blood pressure drops to 100/60.
When the blood pressure is not high enough to deliver adequate blood flow to the organs of the body, the organs may be damaged. Signs of insufficient blood flows to the brain/brain cells include lightheadedness, dizziness, or fainting.
If the blood pressure is already low, standing can make the low pressure worse, to the point of causing severe dizziness and even fainting episodes. This is called orthostatic hypotension. Under normal conditions, the body compensates rapidly for the low pressure created by standing using various automatic responses mediated by the autonomic nervous system (ANS). If there is dysfunction in the ANS (as frequently seen in advanced Adrenal Fatigue) orthostatic hypotension may be exhibited.
Adrenal Fatigue and Blood Pressure
Adrenal Fatigue should not be confused with another medical condition called Addison’s disease, where the adrenal glands are not functioning. While Addison’s disease is often caused by autoimmune dysfunction, Adrenal Fatigue is largely caused by stress. Adrenal Fatigue is the non-Addison’s form of adrenal dysfunction in a sub-clinical form. If you have symptoms such as tiredness, fearfulness, allergies, frequent influenza, arthritis, anxiety, depression, reduced memory and difficulties in concentrating, insomnia, feelings of being worn-out, and the inability to lose weight after extensive efforts, you may be suffering from Adrenal Fatigue (technically known as hypoadrenia).
Typical blood pressure of a person in Adrenal Fatigue ranges from normal to high in early stages and then progresses to low in later stages.
When the body is under stress, blood pressure usually goes up first as the body releases chemicals that raise blood pressure. This in turn sets off a series of compensatory responses resulting in normalization of blood pressure if the body functions are intact and no symptoms surface. Dysfunction of such compensatory mechanisms leads to persistent high blood pressure. This picture changes drastically, however, if because of stress, the adrenals become exhausted and are unable to mount a compensatory response. In this case, blood pressure usually drops below normal as the compensatory mechanism fails. This is especially prominent during postural changes.
Blood pressure in a normal person usually drops as a person stands after lying down due to gravitational forces. This drop immediately triggers the ANS, which causes the blood pressure to return to normal accounting for some overshoot. The rise in pressure on standing usually ranges from 10-20 mm Hg. This overshoot normalizes in a short time and the overall blood pressure returns to normal. A healthy person will not feel this behind the scenes automatic compensatory response under normal circumstances. If the blood pressure drops instead of rises on arising, it is called postural hypotension. There are many causes of postural hypotension, from dehydration to heart disease. It is important to have a thorough conventional medical investigation if the symptoms are clinically significant.
Blood pressure can be low at rest and not considered abnormal. Many have low resting blood pressure under 90/60 and function very well.
The key determinant of whether low blood pressure is clinically significant is whether it is accompanied by symptoms, and whether or not it is postural related.
Symptoms of low blood pressure include dizziness and lightheadedness. In Adrenal Fatigue, low blood pressure usually occurs at rest. However, it can be more prominent when there is postural change. In severe cases, sufferers cannot maintain a standing posture for extended time without sitting down. Multiple trips to the emergency room and extensive workups are not uncommon. Conventional investigative studies often are unremarkable and futile while symptoms become more pronounced over time as Adrenal Fatigue progresses.
The key hormones responsible for blood pressure regulation in the Adrenal Fatigue setting are aldosterone and cortisol. Both are low in advanced stages of Adrenal Fatigue such as adrenal exhaustion. Aldosterone is a hormone secreted by the adrenal cortex, which is part of the rennin-angiotensin-aldosterone system (RAS), which regulates blood pressure. Cortisol is a hormone that is secreted by the adrenal cortex under the direction of the Hypothalamus-Pituitary-Adrenal (HPA) axis and is a main anti-stress hormone. Low aldosterone and cortisol levels both lead to low blood pressure. When the blood pressure drops, blood flow to the brain reduces. A person becomes dizzy and lightheaded. The body then automatically activates its emergency repair system. The ANS is activated as a compensatory mechanism, with associated symptoms such as heart palpitations, increased heart rate, skin pallor, increased strength of each heartbeat, increased respiratory rate, and fainting in severe cases.
Common Causes of Low Blood Pressure
The following are important causes of low blood pressure that need to be investigated prior to considering Adrenal Fatigue as the culprit.
Dehydration. Dehydration reduces the volume of blood and reduces cardiac output (the amount of blood pumped by the heart). It is common among patients who have prolonged vomiting, diarrhea, nausea, and Adrenal Fatigue. Paradoxically, dehydration is also a common cause of high blood pressure as the body may overcompensate by constricting blood vessels in order to prevent reduced low pressure in early Adrenal Fatigue and normal people alike. In fact, taking more fluid can be quite helpful in the majority of essential hypertension cases in its early stages.
Heart disease. Heart disease such as weakened heart muscle, pericarditis, bradycardia, arrhythmias, heart block, and tachycardia can also lead to low blood pressure as the heart is unable to maintain the stroke volume to supply adequate blood flow to the body. Arrhythmia is more prevalent in those with ANS dysfunction. Persistent overtones of the SNS increase the release of norepinephrine. Chronic increases of norepinephrine can lower the heart’s threshold for cardiac arrhythmia, which is commonly seen in Adrenal Fatigue.
Medications. Medications such as calcium channel blockers, beta-blockers, and digoxin (Lanoxin) can slow the rate at which the heart contracts. Elderly people are especially susceptible. Medications used in treating high blood pressure can excessively lower blood pressure and result in symptomatic low blood pressure as well. Water pills (diuretics) such as furosemide (Lasix) can decrease blood volume by causing excessive urination. Medications for treatment of Parkinson’s disease, such as levodopa-carbidopa (Sinemet), and medications used for treating depression, such as amitriptyline (Elavil), erectile dysfunction (impotence), such as sidenafil (Viagra), vardenafil (Levitra), and tadafil (Cialis) when used in combination with nitroglycerine, can cause low blood pressure.
Less common causes include septicemia, alcoholism, diabetes, shock, kidney disease, vasovagal reaction, micturition syncope, anaphylaxis, and certain rare neurological syndromes such as Shy-Drager syndrome that damage the ANS, and Addison’s disease.
In the absence of any of the above-mentioned causes after a full conventional medicine investigation, Adrenal Fatigue should be considered.
We shall now examine each of these three major contributors to blood pressure dysregulation in Adrenal Fatigue aldosterone, cortisol, and the autonomic nervous system (ANS) in detail. These three form an intricate web of interdependency and interactions that ultimately determine blood pressure.
Aldosterone is a chemical that regulates the amount of salt in the body. It is a very specific compound responsible for maintaining the concentration of sodium and potassium inside and outside the cell. This in turn has a direct effect on the amount of fluid in the body and thus blood pressure.
It is manufactured in the adrenal cortex under the direction of another hormone called ACTH (adrenocorticotrophic hormone). ACTH is produced by the anterior pituitary gland. ACTH stimulates the adrenal cortex to secrete a wide variety of hormones including aldosterone as well as cortisol. Like cortisol, aldosterone follows a diurnal pattern of secretion, peaking at 8 a.m., and at it’s lowest from 12-4 a.m.
It is important to note that in our body, sodium and water go hand in hand. Where sodium goes, water follows. As the concentration of aldosterone rises in the body, the concentration of sodium and water rises; thus more fluid is retained in the body and blood pressure rises. Conversely, when the level of aldosterone lowers, the amount of sodium and water in the body is reduced. Therefore, the blood pressure goes down.
As mentioned earlier, aldosterone is part of the rennin-angiotensin-aldosterone system (RAAS) that is responsible for regulating and maintaining sodium balance in the body. Dietary sodium restriction stimulates RAAS activity, while sodium loading reduces the RAAS activity.
Along with the SNS, the brain therefore has two primary regulatory systems that it relies on to maintain appropriate levels of blood pressure, cardiac filling volume, blood volume, and potassium/sodium balance in the body.
Unlike cortisol, aldosterone does not have its own negative feedback loop when there are excessive amounts. If the aldosterone level is too high, aldosterone receptor sites are down regulated and its sensitivity to aldosterone is reduced. In the early phases of Adrenal Fatigue, the amount of cortisol and aldosterone increases in our body due to the ACTH stimulatory effect from stress. As a result, the sodium and water are retained in the body with a feeling of being bloated. The baro-receptors (receptors that are sensitive to pressure) of the blood vessels are triggered and blood vessels go into a relaxation mode automatically, which is regulated by the ANS. This auto-regulation helps to maintain a stable blood pressure at a time when the total fluid volume increases due to high level of aldosterone triggered by stress. With stress, the adrenal glands also secrete another hormone called epinephrine. This hormone constricts the blood vessels and increases blood pressure in order to ensure that our brain has adequate blood flow and oxygen to help us deal with impending danger. The sum reaction of aldosterone and other chemical messengers including cortisol, norepinephrine, acetylcholine, and epinephrine ultimately decides the final blood pressure at any point in time.
During the early stages of Adrenal Fatigue, the resulting blood pressure is often normal if all bodily functions are well balanced. If the body is unable to overcome the aldosterone and epinephrine response, then the blood pressure is elevated. It is common to find many under stress experiencing increases in blood pressure.
As Adrenal Fatigue progresses to more advance stages such as adrenal exhaustion (the third stage of Adrenal Fatigue), the amount of aldosterone production reduces. Sodium and water retention is compromised. As the fluid volume is reduced, low blood pressure ensues. Cells become dehydrated and turn sodium deficient. Hydration is needed to return the body to proper function. Coffee, alcohol, and tea (with the exception of herbal tea) should be avoided.
Many with adrenal exhaustion report a state of low blood pressure as well as salt cravings. The low blood pressure is due to the reduced fluid in the body. Salt cravings are caused by the body’s absolute deficiency of sodium state. Both are due to the lack of aldosterone. In order to compensate for this, potassium is leaked out of the cells so that the sodium to potassium ratio remains constant. The loss of potassium is less than that of sodium, and as a result, the potassium to sodium ratio is increased. This imbalance causes another set of metabolic problems, which further complicates the picture.
Those with adrenal exhaustion often have a low body fluid volume accompanied by salt cravings due to absolute deficiency of sodium as well as a normal to high potassium level. While lost fluids should be replaced, it has to be done carefully and slowly. When the fluid is replaced too quickly without adequate sodium, the amount of sodium in the body may become diluted, resulting in an even lower sodium concentration. Sometimes the replacement is gradual but the body over-reacts, leading to sub-clinical dilutional hyponatremia. Laboratory measurement of common electrolytes may be normal but patients may be presented with full-blown signs of hyponatremia, including confusion, lethargy, nausea, headache, seizure, weakness, and restlessness. Those in this state may find themselves visiting the Emergency Room for the many of these disturbing symptoms only to be told that all is normal after extensive workups.
The body is in turmoil and confused. Using its crude compensatory mechanism to maintain homeostasis to ensure survival of the key organ systems such as the heart and brain first, the rest of the body is thrown into disarray. Secondary function such as electrolyte replenishment takes a back seat and its modulation is compromised. Without a fine modulation mechanism in place, the body goes thru wild swings. The body gets easily dehydrated. If its overall fluid load is not maintained, sub-clinical dehydration occurs and symptoms of adrenal exhaustion worsen.
A relatively easy tactic of increasing blood pressure is simply to take in more salt and water. Salting food liberally as well as taking salt-water drinks can be very helpful. Sea salt is better than table salt because it contains trace minerals. Drinking more water will increase blood volume. This helps those who have chronic hypotension, chronic orthostatic intolerance, neurocardiogenic syncope, and POTS.
Although there are small percentages of people who are sensitive to sodium and develop high blood pressure, the vast majority does not experience an increase in blood pressure, even with moderate salt intake. Those with low blood pressure may see a temporary increase in blood pressure when sodium is added to their diet. Their energy also increases. If heart function is normal, there is no fluid retention, and no signs of edema or other symptoms suggestive of salt sensitivity, then a salt increase in the healthy person will not elevate blood pressure to more than 140/90 (normal being 120/80 mm HG). If the adrenals are weak, increasing salt intake will often enhance adrenal recovery. As the adrenals become stronger, the desire for salt reduces, and excessive salt may make one feel nauseated, especially if the salt is taken with water rather than from salting food. In fact, this is one indication that the adrenal functions are improving.
For some, this replacement is not without complications. The body can sometimes over-react to fluid replacement and trigger a state of sub-clinical dilutional hyponatremia (with confusion, headache etc.) while laboratory electrolyte level is normal. Maintaining the proper balance of solute and fluid requires extensive clinical experience in such cases.
Herbs such as licorice root (Glycyrrhiza glabra) have small blood pressure raising properties but can also be stimulatory; therefore, only small doses should be considered. Harmful herbs to be mindful of include Ephedra (Ma Huang), cola nut or strong black tea as these are very stimulatory in nature and may trigger long-term addiction and withdrawal issues in addition to being known for triggering adrenal crisis. In severe cases, drugs that promote retention of sodium by the kidneys, such as Florinef, may be required.
© Copyright 2013 Michael Lam, M.D. All Rights Reserved.