Understanding ACTH Reference Ranges and Their Meaning
Learn about the ACTH reference range, its normal values in pg/mL, and what these results mean for your health.
Check your result
Calculated in your browser - the number is not sent anywhere.
is below the typical adult range (7–63 pg/mL).
is within the typical adult range (7–63 pg/mL).
is above the typical adult range (7–63 pg/mL).
This number is very far from the usual range - check which unit your report uses.
A value this far outside the range is worth discussing with your doctor today.
What a low result usually means
What a high result usually means
The range printed on your own report comes first - it differs between laboratories. This is not a diagnosis.
See it next to the rest of your report - upload it for a free, private explanationFree. Sign up with your email - no password, we send you a code.Adrenocorticotropic hormone (ACTH) is a hormone produced by the pituitary gland that plays a critical role in stimulating the adrenal glands to release cortisol, a hormone essential for stress response, metabolism, and immune function. Understanding the normal reference range for ACTH and what deviations from this range might indicate can help you better understand your health and when to consult a healthcare provider.
What is ACTH and why is it important?
ACTH, or adrenocorticotropic hormone, is a hormone produced by the pituitary gland located at the base of your brain. Its primary function is to stimulate the adrenal glands, which are located above your kidneys, to release cortisol. Cortisol is crucial for helping your body respond to stress, regulate metabolism, and maintain immune function. Imbalances in ACTH can lead to various health issues, making it important to monitor its levels.
Normal ACTH reference range
The typical reference range for ACTH in adults is approximately 7 to 63 pg/mL. It's important to note that ACTH levels are strongly diurnal, meaning they vary throughout the day, with the highest levels occurring in the morning upon waking. For accurate interpretation, ACTH levels should be paired with a same-time cortisol measurement. This helps provide a more comprehensive picture of your adrenal function and hormone balance.
What can cause abnormal ACTH levels?
Abnormal ACTH levels can be caused by a variety of factors. High levels of ACTH may indicate conditions such as Cushing's disease, where the pituitary gland produces too much ACTH, leading to excess cortisol production. Conversely, low ACTH levels can be seen when the pituitary does not make enough ACTH or after long-term steroid treatment, while in Addison's disease, where the adrenal glands themselves do not produce enough cortisol, ACTH is typically high. Other factors, such as stress, infections, or tumors, can also impact ACTH levels.
How to interpret your ACTH test result
Interpreting your ACTH test result involves considering both the ACTH level and the cortisol level measured at the same time. If your ACTH level falls within the normal range of 7 to 63 pg/mL, and your cortisol levels are also normal, it typically suggests normal adrenal function. However, if either hormone is outside of its normal range, further investigation by a healthcare provider may be necessary to determine the underlying cause.
Frequently asked questions
What time of day should I have my ACTH test? ACTH levels are highest in the morning, so tests are usually conducted early in the day to accurately reflect peak hormone levels.
Can stress affect my ACTH levels? Yes, stress can temporarily increase ACTH levels as part of the body's natural response to stress.
Why is it important to measure cortisol along with ACTH? Measuring cortisol alongside ACTH provides a more complete understanding of adrenal function and helps identify potential hormonal imbalances.
What conditions can affect ACTH levels? Conditions such as Cushing's disease, Addison's disease, stress, and tumors can affect ACTH levels.
Is fasting required before an ACTH test? Fasting is not typically required before an ACTH test, but you should follow any specific instructions given by your healthcare provider.
When to see a doctor
If your ACTH levels are outside the normal range of 7 to 63 pg/mL, or if you experience symptoms such as unexplained weight gain, fatigue, or changes in skin pigmentation, it is important to consult with a healthcare provider. They can help determine the cause of the imbalance and recommend appropriate treatment or further testing.
Decisions about your health should always be made in consultation with your healthcare provider.