Low epinephrine levels typically result from damage to the adrenal glands, problems with the pituitary gland, genetic conditions that block epinephrine production, or certain medications. Because epinephrine plays a central role in your body’s stress response, blood sugar regulation, and blood pressure control, a significant drop can cause noticeable symptoms like dizziness upon standing, fatigue, and difficulty recovering from low blood sugar.
How Your Body Makes Epinephrine
Epinephrine is the final product of a chain of chemical conversions that starts with the amino acid tyrosine. Your body converts tyrosine into dopamine, then into norepinephrine, and finally into epinephrine. That last step depends on a specific enzyme found almost exclusively in the adrenal medulla, the inner core of your adrenal glands. This enzyme needs a methyl donor molecule to do its job, and it also requires high concentrations of cortisol flowing from the surrounding outer layer of the adrenal gland (the cortex) to stay active.
This setup means epinephrine production is vulnerable at multiple points. If the adrenal glands are damaged, the enzyme is missing, or cortisol levels are too low, the final conversion to epinephrine stalls.
Adrenal Gland Damage
The most straightforward cause of low epinephrine is destruction of the adrenal medulla itself. In Addison’s disease, the immune system attacks the adrenal cortex in about 70% of cases. When the disease progresses or when infection or cancer destroys the glands entirely, the medulla is lost along with it, eliminating your primary source of epinephrine.
That said, the body does produce small amounts of epinephrine elsewhere, particularly in the sympathetic nervous system. This is why adrenal medulla loss alone doesn’t always produce dramatic symptoms. The problem becomes more apparent during physiological stress, when the body needs a large surge of epinephrine and can’t generate one. People with adrenal insufficiency are more sensitive to low blood sugar episodes because they lack the normal epinephrine surge that would signal the brain something is wrong and trigger the liver to release glucose. Symptoms during these episodes include tremors, sweating, confusion, weakness, and in severe cases, seizures or loss of consciousness.
Pituitary Gland Problems
Your pituitary gland controls cortisol production by signaling the adrenal cortex. When the pituitary fails (a condition called hypopituitarism, caused by tumors, surgery, radiation, or head trauma), cortisol output drops. This matters for epinephrine because the adrenal medulla sits directly downstream from the cortex, connected by a specialized blood vessel network that delivers cortisol at very high concentrations. Those high concentrations are specifically needed to activate the enzyme that converts norepinephrine into epinephrine.
When pituitary failure suppresses cortisol secretion, the enzyme responsible for making epinephrine becomes less active, and the rate of epinephrine production and release decreases. This is an indirect but clinically meaningful pathway. People with secondary adrenal insufficiency from pituitary disease experience symptoms similar to Addison’s disease, though they typically don’t develop the dark skin patches or severe dehydration seen in primary adrenal failure.
Genetic Enzyme Deficiency
A rare but striking cause of low epinephrine is dopamine beta-hydroxylase (DBH) deficiency, a genetic condition where the enzyme that converts dopamine into norepinephrine is missing or nonfunctional. Without norepinephrine, the body has no precursor to make epinephrine either. Blood tests in affected individuals show plasma norepinephrine and epinephrine below detectable levels (under 25 pg/mL), while dopamine is elevated five to tenfold above normal.
DBH deficiency usually becomes apparent in adolescence, though infants can present with vomiting, dehydration, low blood pressure, low body temperature, and low blood sugar. Older children and adults typically report lifelong lightheadedness, fatigue, inability to tolerate standing, reduced exercise capacity, and frequent fainting. Standing blood pressure often drops below 80 mm Hg systolic. Physical features can include a high-arched palate, hyperextensible joints, low muscle tone, drooping eyelids, and sluggish reflexes. Sweating remains normal because that pathway uses a different chemical messenger.
Autonomic Nervous System Disorders
Pure autonomic failure (PAF) is a degenerative condition affecting the nerve cells that regulate involuntary body functions like heart rate and blood pressure. People with PAF have greatly reduced levels of catecholamines overall. Plasma epinephrine is reduced, though typically not as severely as norepinephrine. The primary symptom is orthostatic hypotension, a sharp drop in blood pressure when moving from lying down to standing, which causes dizziness, visual dimming, and fainting.
Other conditions that damage autonomic nerves, including multiple system atrophy and some forms of Parkinson’s disease, can similarly reduce the body’s ability to release epinephrine in response to stress or positional changes.
Medications That Lower Epinephrine
Several drug classes suppress catecholamine levels, including epinephrine. Clonidine, a blood pressure medication that works by calming the sympathetic nervous system, is one of the most common. Reserpine, which depletes stored catecholamines from nerve endings, also reduces circulating epinephrine. Other medications linked to lower catecholamine measurements include guanethidine, certain antipsychotics (phenothiazines), some antidepressants, and disulfiram (used in alcohol dependence treatment).
If you’re being tested for catecholamine levels and take any of these medications, your results may read artificially low. Labs typically ask about current medications for this reason.
What Normal Levels Look Like
For reference, normal resting plasma epinephrine is under 50 pg/mL when lying down and under 95 pg/mL when standing. These are very small concentrations. Epinephrine is meant to spike during acute stress and return to baseline quickly, so a single low reading in a calm state doesn’t necessarily indicate a problem. Repeated low readings paired with symptoms like orthostatic hypotension, exercise intolerance, or recurrent unexplained low blood sugar episodes are what point toward a true deficiency.
How Low Epinephrine Affects Daily Life
The most practical consequences of low epinephrine fall into two categories: blood pressure regulation and blood sugar control. Without adequate epinephrine, your body struggles to raise blood pressure when you stand up, which is why dizziness and fainting upon standing are hallmark symptoms across nearly all the conditions that cause low epinephrine. People with severe deficiency often instinctively squat when they feel lightheaded, compressing blood vessels in the legs to push blood back toward the heart and brain.
The blood sugar connection is equally important. Epinephrine is one of your body’s primary counter-regulatory hormones, meaning it helps raise blood sugar when it drops too low. Without it, you lose one of the key signals that alert you to a low blood sugar episode (the shaky, sweaty, heart-pounding feeling) and one of the mechanisms that corrects it. This makes hypoglycemia both harder to detect and harder to recover from, which is why unexplained episodes of drowsiness, confusion, or collapse can be an early clue that something is off with epinephrine production.