The adrenal glands are two small, hormone-producing structures that sit on top of the kidneys.

They are made up of two distinct parts:

• the outer cortex – produces steroid hormones including cortisol, aldosterone and sex hormones
• the inner medulla – produces adrenaline and noradrenaline

Disorders of the adrenal glands can result in under- or over-production of particular hormones, depending upon which part of the gland is affected e.g. in Cushing’s syndrome there is an excess of cortisol while in Addison’s disease there is not enough cortisol.