STEROID REPLACEMENT IN ADRENAL INSUFFICIENCY
Steroids are hormones (chemical products of endocrine glands which are
secreted into the blood and carry messsages to other organs) formed in
the body by the outer layer (cortex) of the adrenal glands, two small structures
lying just above the kidneys.
The two most important steroid hormones are hydrocortisone, which has
various functions including
(1) controlling the blood sugar level,
(2) helping the body combat stress and
(3) reducing inflammation, and aldosterone, which regulates the body
content of salt by controlling the rate of salt loss in the urine.
Adrenalin, the hormone involved in the response to fright, is not a
steroid and is secreted by the inner part of the adrenal glands, this system
seldom fails and replacement is not necesssary.
Steroid replacement is needed when the natural secretion of the adrenals
is inadequate. This arises in three different situations
(1) when the drive to the adrenals from the pituitary (an important
endocrine gland located in the head just below the brain) is lost, in addition
to steroids there is then usually need for replacement of some or all of
the other hormones secreted or driven by the pituitary, these are thyroxine,
growth hormone, sex hormones and antidiuretic hormone
(2) in congenital adrenal hyperplasia, a genetic condition in which
there is a block in the production of steroid hormones and
(3) when the adrenal cortex itself fails.
For replacement only small doses of steroids are needed to mimic the
natural secretion of the missing hormones.
Hydrocortisone is available in tablet form (as dividable 20 milligram
(mg), 10mg or 2.5mg tablets) and, if replacement of aldosterone is also
needed, fludrocortisone (dividable 100 microgram (mcg) tablets), an artificial
steroid which has the same action as aldosterone but is more effective
by mouth, is given.
It is usually satisfactory to give hydrocortisone and fludrocortisone
in twice daily doses except in stress as detailed below. The adequacy of
the doses can be checked by occasional tests on blood or saliva.
Side effects:
Because only small doses, aiming to replace the natural secretion of
steroids, are needed for replacement the notorious side effects of high
dose steroid treatment, as sometimes needed to control inflammatory disorders
such as arthritis, and including moon face, obesity, muscle wasting and
thinning of the bones, are not seen. In children too large a dose of hydrocortisone
will cause slowing of growth possibly with some weight gain and too small
a dose a lack of energy and sometimes a tendency to low blood sugar (hypoglycaemia).
Too much fludrocortisone will increase the blood pressure and too little
will lower it and cause salt craving.
Stress:
In order to combat the stress of illness or injury, the natural secretion
of hydrocortisone is increased. Children on treatment with steroids also
need an increased dose to cover such illness. Sudden interruption of replacement
must be avoided. An important principle is therefore that steroid treatment
must be given continuously and and must be increased to cover illness.
If the dose is repeatedly lost through vomiting it MUST be given by injection.
(Do not be too concerned by these warnings, most children on steroids never
need an injection).
The rules of treatment are therefore:
* Devise as reliable as possible a method of giving your child the
medication. Even in the most organised households occasional doses are
missed and fortunately this seldom matters as long as the child is well.
Resume the normal dose as soon as the omission is noted. *
To cover illness (beyond mild coughs and colds which do not require
any change in treatment)
(1) if the child is not eating give regular sweet drinks to avoid a
fall in the blood sugar (hypoglycaemia)
(2) give hydrocortisone in an increased dose (twice the usual morning
dose given every eight hours) as below. It is not necessary to give an
increased dose of fludrocortisone.
Continue the increased dose until the child is well.
* If the child is vomiting increase the dose as above and make sure
that the tablets are retained for at least an hour. If the dose is vomited
in less than an hour repeat it. If there is any doubt that the dose has
been retained it must be given as an injection. If such a situation does
arise it is certainly appropriate to call the GP or take the child to hospital
but all families with a child on steroid replacement need to have available
a 100mg ampoule of hydrocortisone and to know how to make it up and give
it by intramuscular injection in a crisis. *
All children on steroids (or their parents) should carry an engraved
bracelet or necklace and/or a note of the details of the treatment.
Treatment Plan:
..................................'s current steroid treatment is
hydrocortisone............mg (.........tablets) at ........................
............mg (.........tablets) at ........................
fludrocortisone............. ug (...........tablets) at ......................
..............ug (...........tablets) at ......................
To cover illness give hydrocortisone............................................................mg
(............tablets) every 6 hours If an injection is necessary give hydrocortisone
............................mg (............ampoule) every ............hours
STEROID CHECK LIST
- 1. Discussion
- 2. Fact sheet
- 3. Hydrocortisone 100mg ampoule and injection technique
- 4. Card with treatment details
- 5. Necklace or bracelet
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