Synacthen Test: Learn about What is it used for, How does it work

Synacthen test is a chemical test to know if the adrenal glands are making make a chemical (hormone) called cortisol. This test helps to make sure if the adrenal glands are functioning properly or not. Synacthen test involves stimulating the adrenal glands to check if they respond. The chemical which is used in the Synacthen test is tetracosactide. The Synacthen test is performed through an injection administered directly into the muscle by a healthcare professional. 

We have compiled this detailed guide that will help you understand the important details of this test. However, the information we have provided here works as a general guide, the arrangement for the test may vary between different hospitals.

What are Adrenal Glands and Where are they Found?

Before we dive deeper into understanding the Synacthen test, let us understand the glands on which the test is performed. Adrenal glands are also known as endocrine glands, which release hormones (chemicals) into your bloodstream. These hormones act as a messenger which affects the cells and tissues in distant parts of your body. Adrenal glands play a vital role in our body for they produce hormones that help control a number of our body’s functions. Adrenal glands are found just above each kidney and are two in number. They are about the size of a walnut. The cells in different parts of the adrenal glands produce different types of chemicals called hormones.

How does the Synacthen Test Work?

The Synacthen 0.25 mg/ml injection contains a chemical tetracosactide, which is a chemical copy of ACTH. For those who may not be aware, ACTH is a chemical released by our pituitary gland, which further stimulates the adrenal glands to produce cortisol. 

If the adrenal glands are functioning well, they would respond are working properly they should respond to the tetracosactide by producing cortisol. However, if the level of cortisol (hormones) remains low despite the Synacthen injection, it suggests that there is a problem with the functioning of the adrenal glands.

How is the Synacthen Test Carried out?

Synacthen test is carried out in several ways depending on your local hospital. However, the general procedure remains to be the same which can be encapsulated in the following points - 

• Synacthen test is usually done in the morning, as the cortisol levels vary throughout the day. Hence you will be asked to come to the hospital first thing in the morning.
• As part of the test,  a sample of your blood will be taken to check how much cortisol is present before stimulating your adrenal glands.
• Thereafter a small needle will be put into your vein or in the muscle to inject tetracosactide.
• Within 30 minutes of injecting tetracosactide, another blood sample will be taken, to check the level of cortisol and to see if the adrenals have responded to the test.
• This is also known as the short synacthen test, post which you are free to leave the hospital
• However in the case of the 'long synacthen test' blood samples are taken at the start of the test, followed by injecting tetracosactide. Thereafter, blood samples are taken at regular intervals over a period of 24 hours.

Who cannot have the Synacthen Test?

Although the Synacthen test does not have potentially serious side effects, it is not meant to be done by certain people. We have listed below the set of people who must not take the Synacthen Test- 

• Preganant Women
• Anyone who has undergone an operation on the pituitary gland and it has not been six weeks since then.
• Anyone who is taking an oral contraceptive pill or hormone replacement therapy
• Anyone on steroid tablets ( However they will be eligible for the test if they do not take the tablets 24 hours before this test)

Key Takeaways

Synacthen injection is manufactured by Curatis and is not readily marketed in India. With limited market availability, the Synacthen test becomes hard to perform. However, our platform JollyRX, an online portal, is meant to make hard-to-find drugs and diagnostics easily accessible. Hence, one can purchase the Synacthen injection through JollyRX at an affordable price.