Cortisol AM & PM

What is Cortisol and the Cortisol AM & PM test?

Cortisol is your natural built-in alarm system that works in parallel with many parts of your brain to control your mood, motivation and fear. When you are in a stressful situation, such as having a dog barking at you, your body produces cortisol. Cortisol is a hormone that is produced and secreted by the adrenal glands that are triangular organs located on our kidney. It is transported through the blood and is regulated by the hypothalamus (in the brain) and the pituitary glands (a small organ located below the brain). When the levels of cortisol decrease in your blood, the hypothalamus secretes a corticotropin releasing hormone that pushes the pituitary gland to produce the adrenocorticotropic hormone (ACTH). This latter stimulates the secretion of cortisol. When you are healthy and have the right amounts of cortisol in your system, this indicates that your hypothalamus, pituitary and adrenal glands are functioning as they should.

The level of cortisol in our body is very significant. When levels are either too low or too high, health issues may arise that can range from mild to serious. When your cortisol levels are too high, your body will show symptoms such as gaining weight fast, having high blood pressure and muscle weakness, as well as witnessing severe mood swings that are caused by anxiety and depression. If your cortisol levels are too low; then, you may experience dizziness, fatigue, weight loss, and darkening spots in specific areas of your skin.

Our body has an internal clock when it comes to cortisol. It can regulate cortisol levels throughout the day. In the morning, levels are normally elevated with a tendency to increase significantly 20-30 minutes after waking up. This is referred to as the cortisol awakening response. Throughout the day, cortisol levels plunge down to reach their lowest at night. This diurnal rhythm helps the body regulate its sleep: cortisol levels drop to allow the body to rest at night and replenish in the morning with the hormone’s high levels secreted. This rhythm is inverted for those who work at night and sleep during the day.

Stress affects the levels of cortisol, as well. When you fall down or have an argument with someone, your body may witness a peak in its cortisol levels that is short-term. Being exposed to long term stress, like work related stress, can increase the levels of cortisol that remain constantly high throughout the day. In that case, the body will start having adrenal fatigue that leads to the depletion of nutrients and precursors needed for the body to keep producing cortisol as needed. So, constant stress elevates the levels of cortisol for some time, after which they start declining. The decline is not only witnessed for cortisol levels, but also for other neurotransmitters like aldosterone, testosterone, epinephrine, and others. Such stress and depletions will affect the diurnal rhythm. This is why a person normally feels burnout after a period of stress, which is witnessed as extreme fatigue, lack of enthusiasm, insomnia and lack of vitality. Such effects can be reserved by eating well, taking the right supplements and adapting stress relieving techniques.

This Cortisol AM & PM test measures the level of cortisol by taking two different samples: one during the morning, and another one later on in the afternoon. Both samples are obtained from the same day. They can help give a feedback about the fluctuations of cortisol levels within the same day.

Why take the Cortisol AM & PM test?

Cortisol is a hormone that is responsible for many systems in our body. It supports bone growth, controls blood pressure, manages our immune system, helps our nervous system function properly and lets our body reacts well to stress. Cortisol can also play a major role in the metabolism of fats, carbohydrates and proteins.

Getting tested for cortisol is an important tool to diagnose Cushing syndrome as well as primary and secondary adrenal insufficiency. It also helps detects any malfunctions and conditions affecting the proper functioning of the pituitary and adrenal glands. Even after there was a diagnosis of Cushing or Addison disease, getting tested for cortisol can help monitor the effectiveness of the treatment chosen. If you have symptoms of high or low cortisol levels, you need to get tested.

What can cause abnormal levels of Cortisol AM & PM?

Many factors may affect the results of a cortisol AM PM test. For example, depression, hyperthyroidism, hypoglycemia, obesity, pregnancy and stress can cause high levels of cortisol. On the other hand, liver cirrhosis, hepatitis and hypothyroidism may cause these levels to drop below normal.

When it comes to drugs, some increase while others decrease cortisol levels. Medicines that cause levels to drop include androgens, aminoglutethimide, betamethasone, danazol, lithium, levodopa, metyrapone, phenytoin, and exogenous steroid medications. Drugs that cause high levels include amphetamines, cortisone, estrogen, oral contraceptives, and spironolactone.

What your Cortisol AM & PM results mean?

Results of this test need to be well interpreted. First of all, since there are two samples, it is wise to know that the expected levels of cortisol in the morning are expected to be between 5 and 23 mcg/dL around 8am and between 3 and 13 mcg/dL around 4pm. Normal levels of cortisol between 8 AM and noon should be between 5 and 23 mcg/dL; and, between 0 and 10 mcg/dL if the sample was obtained between 8 PM and 8 AM.

Levels higher than normal, are caused by tumors on the pituitary or adrenal glands that can cause Cushing syndrome that is characterized by a flushed round face, high blood pressure, and the accumulation of fat in the abdominal area.

Lower than normal levels of cortisol can be caused by primary or secondary adrenal insufficiency. This is referred to as Addison’s disease. It may also indicate that you have hypopituitarism, which is a malfunction in the pituitary gland that is not sending the proper signal leading to the proper production of cortisol.

Since stress plays a major role in increasing your cortisol levels, you may want to take the test at a time when you are minimally stressed. Those who face a lot of stress at work or in their personal life, need to take the test numerous times and at different days to make a better diagnosis.

Where can I get a Cortisol AM & PM test near me?

Please use our Lab Locator to find find a convenient testing location.

Reviewed By: Dr. Kurt Kloss, MD
Last Reviewed Date: Aug 27, 2021