Examinations
Examinations
Epinephrine (Adrenaline) – A Catecholamine Hormone
Epinephrine (adrenaline) is a catecholamine and the primary hormone of the adrenal medulla. It is synthesized in the adrenal glands from norepinephrine through enzymatic reactions and is stored in chromaffin cells.
During stress, blood loss, or intense physical activity, the adrenal glands secrete epinephrine in increased amounts, triggering the fight-or-flight response.
Physiological Effects of Epinephrine
- Increases blood pressure by constricting blood vessels in the skin, gastrointestinal tract, and skeletal muscles.
- Enhances coronary blood flow.
- Stimulates and accelerates heart rate.
- Raises blood glucose levels by stimulating glycogen breakdown in the liver.
- Primary source of circulating epinephrine: adrenal glands.
For children under 1 year: No food for 30–40 minutes before the test.
For children aged 1–5 years: No food for 2–3 hours before the test.
Other restrictions:
- No food for 12 hours before the test (only water is allowed).
- Discontinue sympathomimetics 14 days before the test (as per physician’s guidance).
- Avoid all medications 24 hours before the test (as per physician’s guidance).
- Eliminate physical and emotional stress 24 hours before the test.
- Do not smoke for at least 2 hours before the test.
- Suspicion of a chromaffin tumor (pheochromocytoma, neuroendocrine tumors).
- Chronic hypertension with symptoms like headaches, sweating, and rapid pulse.
- Hypertension that is resistant to standard treatment (patients with chromaffin tumors often do not respond to traditional antihypertensive therapy).
- Detection of adrenal or neuroendocrine tumors on imaging or genetic predisposition to tumor formation.
- Monitoring patients after treatment for chromaffin tumors.
Many factors can influence epinephrine levels, leading to false-positive results. Since chromaffin tumors are rare, an isolated elevation in catecholamine levels is not always diagnostic.
To ensure an accurate diagnosis, comprehensive evaluation is required, including:
- Assessment of the patient's physical and emotional state.
- Review of medications and dietary intake.
- Repeat testing after correcting interfering factors to determine if catecholamine levels remain elevated.
Additional tests for confirmation may include:
- Blood and/or urine tests for metanephrines (epinephrine metabolites).
- MRI scanning for tumor localization.