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| CANTERBURY HEALTH LABORATORIES |
Cortisol is a hormone made by the adrenal glands which sit on top of each kidney.
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The adrenal gland makes several hormones. The inner zone (medulla) makes adrenaline. The outer zone (cortex) supplies cortisol as well as other hormones controlling salt balance (aldosterone) and sexual development (sex steroids). |
Of these hormones, only cortisol is essential to life, though the salt balance hormone (aldosterone or its substitute, fludrocortisone) may be needed to assist the action of hydrocortisone in some people with inadequate adrenal gland activity.
Hormones are the chemical messengers in the body. They are produced in one part of the body by an endocrine or hormone-producing gland, and act somewhere else in the body. For example the female sex hormone oestrogen is made in the ovaries and acts elsewhere to cause breast enlargement, broadening of the hips, and menstrual periods.
There are many different types of hormones and many endocrine glands which make their own special hormones.
The adrenal glands are a pair of fleshy triangular-shaped organs, each about the size of a walnut, which lie above the kidneys, on the back wall of the abdomen.
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Cortisol is secreted into the blood stream in response to the regulating hormone called ACTH which is in turn produced
by the pituitary gland under the brain. If too much cortisol is secreted, the pituitary hormone output is reduced. Apart from regulating the secretion of the adrenal glands, ACTH has no other known function although it does darken the skin if the blood level is abnormally high for long periods of time. |
There are several reasons why cortisol deficiency occurs. Your doctor will describe which one is responsible in your case.
Adrenal Gland Atrophy
For some reason, often unknown, the adrenal gland wastes away and can no longer respond to ACTH. This happens in Addison's disease, and people with this disorder will require hydrocortisone and other hormone treatment (e.g. fludrocortisone or florinef) for the rest of their lives. The commonest cause of adrenal failure is a problem with the body's immune system. Occasionally it can result from tuberculosis of the adrenal glands.
Disorders of Synthesis
In this case the adrenal gland is present and active, but lacks the ability to make the final product (cortisol/hydrocortisone). Immature forms of the hormone are made instead and these can lead to abnormal developments (rapid growth in children, excessive sex hair and premature male development, infertility etc) if not controlled. This condition is called congenital adrenal hyperplasia and requires treatment with hydrocortisone for life. These people sometimes need fludrocortisone also to normalize the salt balance of the body.
Removal by Surgery
The adrenal glands may have been removed by surgical operation. Hydrocortisone and probably fludrocortisone treatment will be needed for life.
Lack of ACTH from the pituitary
If the pituitary gland cannot make ACTH then a lack of cortisol develops because ACTH controls the activity of the adrenal glands. This can happen if the base of the brain is damaged, or if the pituitary gland is squashed or has to be removed for any reason. This condition is treated with hydrocortisone, usually required for life or until the pituitary can recover sufficiently to make enough ACTH. If the pituitary gland is not working properly there may be a number of other hormones which will need to be replaced. Your doctor will instruct you on the need for checks to assess this.
The functions of cortisol in the body are many.
It is especially important in helping the body to combat stress or recover from any shock or illness.
It controls metabolism - the supply of glucose and energy, allows the muscles to perform efficiently, helps to regulate blood pressure and to fight off infections. Cortisol also helps to maintain appetite and body weight.
Hydrocortisone - most commonly used for replacement therapy. Comes in 5mg and 20mg tablet form.
Cortisone acetate - similar in action to hydrocortisone, comes in 5mg and 25mg tablet form.
Other hormone medications with a similar action are prednisone and dexamethasone.
Usually hydrocortisone is taken on a "twice a day" basis. The main or larger dose is usually taken on getting up each morning and a second dose is taken later in the day. Always take the tablet with food as indigestion could develop if taken on an empty stomach. Try to take the pills at a set time each day so you will remember them more easily. If you have forgotten a dose (or can't remember if you took it or not) take the pills anyway, rather than omit a dose.
NEVER LET YOUR PILLS RUN OUT as it is dangerous to go without treatment.
Your dose of medication was chosen according to your age, sex, weight and progress on the tablets. It is important to realize that you are simply taking a replacement dose of a hormone normally present in the body, so you shouldn't be prone to the complications of "high doses of steroids" that may occur in patients required to take very large doses to suppress some other disease e.g. some arthritis or respiratory conditions. If you were not taking enough hydrocortisone, you would feel faint and exhausted and become nauseated and inclined to vomit.
If you were taking too much hydrocortisone the signs are harder to detect until well developed. Weight gain, rounding of the face, bruising, ankle swelling, high blood pressure and eventually muscle weakness, thinning of the bones and mood changes can occur.
Yes, you should be able to do what you wish including sports and other recreational activities. As long as you watch your weight, keep as close to "ideal" as possible, and remember your pills each day you should have a normal life expectancy and normal quality of life.
Check with your doctor or pharmacist before starting other pills. Common medications (aspirin, antibiotics, panadol, sleeping pills) will not affect treatment but thyroid pills and drugs for epilepsy (anti-convulsants) could interact. These need to be checked by your specialist. Vaccinations and 'flu vaccinations can be given if required. You may be more sensitive to alcohol than you used to be.
When a person with normal adrenal function gets an infection ('flu or a bout of diarrhoea, vomiting etc) or has any accident or surgical operation, the adrenal gland responds promptly by putting out much more cortisol - at least for the first day or so of the "illness".
This response of the adrenal glands helps the body to ward off the infection and assists prompt recovery. If the adrenal glands for some reason cannot increase their output, there is a danger of collapse and severe shock developing unless extra hydrocortisone is given.
For this reason all people (dependent on cortisol) should wear a medic-alert bracelet or emblem so that extra hormone can be given in an emergency, especially if consciousness is impaired.
Make sure you have a Medic-Alert bracelet and always wear it!
Double your usual dose of hydrocortisone if you are unwell enough to stay confined to bed (e.g. fever or 'flu episode). You can continue to take double the usual dose for one or two days, by then you should be improving. IF NOT YOU MUST CONTACT YOUR DOCTOR.
If vomiting or unable to swallow your tablets contact your doctor URGENTLY. Usually you will be given an injection of hydrocortisone (50 - 100mg). This may be repeated in 6-8 hours if you are still unable to swallow pills.
If vomiting and/or diarrhoea continues for longer than 8 - 12 hours you MUST BE ADMITTED TO HOSPITAL and kept under close medical observation.
If you live far away from a medical centre you may need to have a supply of injectable hydrocortisone, syringes and needles in case of emergency. This can be arranged through your specialist or G.P.
Any accident (fracture, burn etc), surgery, anaesthetic, dental extraction etc will need extra hydrocortisone. Note: It is not necessary to change the fludrocortisone dose during stress, if you are taking these pills. Emotional shocks, "head colds", increased exercise do not usually require extra hydrocortisone.
Usually no special difficulties but check with your specialist to be sure your dose is satisfactory. You will need extra hydrocortisone at the time of delivery and this will be organised by your specialist and obstetrician.
Have adequate supplies of pills.
Carry a summary of your medical history with you.
Don't take risks with hygiene. Tummy bugs can be very unpleasant.
Department of Endocrinology
Christchurch Hospital
Christchurch, New Zealand
Phone (03) 364 0927
