Adrenocorticotropic Hormone Risks and Side Effects

The Adrenocorticotropic Hormone (ACTH) test measures the amount of ACTH in your blood, a hormone that helps control your body's stress response. This test helps doctors check how well your adrenal and pituitary glands are working. Risks are generally low, mainly involving minor discomfort from the blood draw itself. Side effects are rare, typically limited to bruising or temporary lightheadedness. Your clinician will interpret your results.

What is Adrenocorticotropic Hormone Risks and Side Effects?

The Adrenocorticotropic Hormone (ACTH) test measures the level of ACTH in your blood. ACTH is a hormone made by your pituitary gland that tells your adrenal glands to produce cortisol, a stress hormone. This test helps identify problems with your pituitary or adrenal glands, which can affect many body functions. Risks are minimal, primarily related to the blood draw.

Adrenocorticotropic hormone (ACTH) is a crucial hormone produced by the pituitary gland, a small gland located at the base of your brain. ACTH's main job is to stimulate your adrenal glands, which sit on top of your kidneys, to release cortisol. Cortisol is often called the "stress hormone" and plays a vital role in many body functions, including metabolism, immune response, and blood pressure regulation. An ACTH test measures how much of this hormone is in your bloodstream. Doctors order this test to investigate conditions where the body produces too much or too little cortisol. For example, it can help diagnose adrenal insufficiency (Addison's disease), where the adrenal glands do not make enough cortisol, or Cushing's syndrome, where the body has too much cortisol. By checking ACTH levels, your doctor can determine if the problem lies with your pituitary gland, which makes ACTH, or with your adrenal glands, which respond to ACTH. This distinction is important for guiding further diagnostic steps and treatment plans. The test provides valuable information about the complex hormonal balance in your body.

Why it's ordered

Your doctor orders an ACTH test to investigate symptoms that suggest an imbalance in cortisol production, which can be caused by problems with your pituitary or adrenal glands. These symptoms might include unexplained weight changes, fatigue, muscle weakness, or changes in blood pressure. The test helps pinpoint the source of these hormonal issues.

Doctors commonly order an ACTH test when you show symptoms related to abnormal cortisol levels. If your body produces too little cortisol, you might experience extreme tiredness (fatigue), muscle weakness, weight loss, low blood pressure (hypotension), and skin darkening. These symptoms can point to adrenal insufficiency, such as Addison's disease. Conversely, if your body produces too much cortisol, you might have symptoms like weight gain, especially around your midsection and face, high blood pressure (hypertension), muscle weakness, and thin skin that bruises easily. These signs can indicate Cushing's syndrome. The ACTH test is crucial for determining whether the problem originates in the adrenal glands themselves (primary adrenal insufficiency or adrenal tumor causing Cushing's) or in the pituitary gland, which controls the adrenal glands (secondary adrenal insufficiency or pituitary tumor causing Cushing's). Understanding the source helps your doctor choose the correct treatment.

How to prepare

Preparing for an ACTH test usually involves following specific instructions from your doctor to ensure accurate results. You may need to fast for a certain period before the test, meaning no food or drink except water. Your doctor might also ask you to avoid certain medications or strenuous exercise beforehand, as these can affect hormone levels.

To ensure the most accurate results for your ACTH test, your doctor will provide specific preparation instructions. Often, you will be asked to fast for 8 to 12 hours before the blood draw. This means you should not eat or drink anything except water during this time. Fasting helps prevent certain foods or drinks from affecting your hormone levels. It is also very important to discuss all medications, supplements, and herbal remedies you are taking with your doctor. Some medications, particularly corticosteroids (steroids) and biotin supplements, can interfere with ACTH test results. Your doctor may advise you to temporarily stop taking certain medications or adjust their dosage before the test. Never stop or change medications without your doctor's guidance. The timing of the ACTH test is also important because ACTH levels naturally change throughout the day, usually being highest in the morning. For this reason, your blood sample is typically drawn between 7:00 AM and 10:00 AM. Try to avoid strenuous exercise and significant stress before the test, as these can also influence hormone levels.

What to expect during

During an ACTH test, a healthcare professional will draw a blood sample, usually from a vein in your arm. The process is quick and similar to any standard blood test. You might feel a brief pinch or sting as the needle is inserted. The collected blood sample is then sent to a lab for analysis of your ACTH levels.

The ACTH test is a routine blood test performed in a clinic, hospital, or laboratory setting. A healthcare professional, such as a nurse or phlebotomist, will typically draw a blood sample from a vein in your arm, usually on the inside of your elbow. They will first clean the area with an antiseptic wipe. Next, a tourniquet (a tight band) will be placed around your upper arm to make the veins more visible and easier to access. You will be asked to make a fist. The healthcare professional will then gently insert a small needle into the vein. You may feel a brief pinch or sting when the needle goes in. Once enough blood has been collected into a small tube, the tourniquet will be removed, and the needle will be withdrawn. Pressure will be applied to the site with a cotton ball or gauze, and a bandage will be placed over it. The entire blood collection process usually takes only a few minutes. The blood sample is then labeled and sent to a laboratory for analysis.

Understanding your results

Understanding your ACTH test results requires careful interpretation by your doctor, who will consider them alongside your symptoms, medical history, and other test findings. General results indicate whether ACTH levels are high, low, or within a normal range. These levels help your doctor determine if your pituitary or adrenal glands are functioning correctly or if there's an underlying condition.

Your ACTH test results will be sent to your doctor, who is best equipped to interpret them in the context of your overall health. It is important to remember that a single test result rarely provides a complete picture. Your doctor will consider your symptoms, medical history, and the results of any other tests you have had. Generally, high ACTH levels can suggest that your pituitary gland is overproducing ACTH, possibly due to a tumor (like in Cushing's disease), or that your adrenal glands are not responding adequately to ACTH (as in primary adrenal insufficiency). Conversely, low ACTH levels might indicate that your pituitary gland is not producing enough ACTH (secondary adrenal insufficiency) or that your adrenal glands are overproducing cortisol independently (like an adrenal tumor causing Cushing's syndrome). Normal ACTH levels, when combined with abnormal cortisol levels, can also provide important diagnostic clues. Your doctor may order additional tests, such as a cortisol stimulation test or imaging scans, to confirm a diagnosis and determine the exact cause of any hormonal imbalance. Always discuss your specific results and what they mean for your health with your healthcare provider.

Risks

The risks associated with an ACTH blood test are generally minimal and similar to those of any routine blood draw. The most common side effects include minor pain, bruising, or tenderness at the needle insertion site. More serious complications are rare but can include infection or excessive bleeding. Always inform your healthcare provider if you have concerns.

The ACTH blood test is considered a very safe procedure with few risks. The most common side effects are minor and temporary. You might experience slight pain or tenderness at the site where the needle was inserted. A small bruise (hematoma) can also form under the skin, but this usually resolves on its own within a few days. Some people may feel dizzy or lightheaded during or immediately after the blood draw. More serious complications are rare. These can include infection at the puncture site, especially if the area is not kept clean, or excessive bleeding, particularly for individuals on blood-thinning medications or with bleeding disorders. In very rare cases, a vein might become inflamed (phlebitis), but this is also usually mild and resolves with warm compresses. If you experience any unusual or severe symptoms after your blood test, such as persistent pain, swelling, redness, or signs of infection, contact your doctor or the clinic immediately. Inform the healthcare professional drawing your blood if you have a history of fainting during blood tests, have bleeding disorders, or are taking any medications that affect blood clotting.

Frequently asked questions

Can stress affect my ACTH test results?

Yes, stress can influence your ACTH levels. Both physical and emotional stress can cause your body to release more ACTH, which then stimulates cortisol production. To ensure accurate test results, your doctor might advise you to avoid strenuous activity and try to remain calm before your blood draw. Always follow your doctor's specific preparation instructions.

How long does it take to get ACTH test results back?

The time it takes to receive your ACTH test results can vary, but it usually takes a few business days. The blood sample needs to be processed in a laboratory, and then the results are sent to your doctor. Your doctor will then review the results and discuss them with you during a follow-up appointment.

Do I need to stop eating or drinking before an ACTH test?

Yes, in most cases, you will need to fast before an ACTH test. This means you should not eat or drink anything except water for 8 to 12 hours before your blood sample is taken. Fasting helps ensure that food and drink do not interfere with the accuracy of your hormone levels. Always confirm specific fasting instructions with your doctor.

Can medications affect my ACTH test results?

Yes, certain medications can significantly affect ACTH test results. Corticosteroids (steroids) are a common example, as they can directly influence cortisol and ACTH levels. Biotin supplements can also interfere with some lab tests. It is crucial to tell your doctor about all medications, supplements, and herbal remedies you are taking before the test.

Is the ACTH test painful?

The ACTH test involves a standard blood draw, which typically causes only minor and brief discomfort. You might feel a quick pinch or sting when the needle is inserted into your vein. Most people find the procedure tolerable. If you are particularly anxious about needles, inform the healthcare professional beforehand.

What is the difference between an ACTH test and a cortisol test?

An ACTH test measures the level of adrenocorticotropic hormone from your pituitary gland, while a cortisol test measures the level of cortisol, a hormone produced by your adrenal glands. These two tests are often ordered together because ACTH controls cortisol production. Comparing both levels helps doctors pinpoint the source of a hormonal imbalance.

Sources

• MedlinePlus — Adrenocorticotropic Hormone Risks and Side Effects
• Mayo Clinic — Adrenocorticotropic Hormone Risks and Side Effects
• Cochrane Library — Adrenocorticotropic Hormone Risks and Side Effects