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What you should know about Protirelin Ampoules
This leaflet contains information about Protirelin Ampoules,
which are administered by a doctor or nurse as part of the
test you are about to have done. Although you will not be
taking this medicine or giving it to your child yourself, this
leaflet contains important information to help you
understand how Protirelin is used. If there is anything you
do not understand, please ask a doctor or nurse.
This leaflet is written for the patient who is to have the test.
If you are the parent of a child who is going to have the test,
then of course the information should be read as applying
to the child.
What do Protirelin Ampoules contain?
Each ampoule contains 200micrograms of Protirelin (the
active ingredient) together with some other ingredients
which are as follows:
Mannitol Ph.Eur, Glacial Acetic Acid Ph.Eur, Water for
Protirelin Ampoules, coded with orange and black colour
rings contain 2ml of a solution for injections. The solution
contains 100micrograms of Protirelin per ml and is supplied
in packs of 10 ampoules.
Protirelin is a diagnostic agent, which means that it is used in
tests rather than as a treatment for a disease. The active
ingredient of Protirelin Ampoules (Protirelin, also known as
TRH) is a hormone which is produced by a part of the brain
called the hypothalamus and acts on the pituitary gland
which is situated very close to the hypothalamus. Protirelin
causes the pituitary gland to release another hormone
which in turn travels round in the blood stream and acts on
another gland, the thyroid gland in the neck. The thyroid
gland itself produces more hormones which help to control
the body's metabolism - the chemical reactions that are
going on inside us all the time.
The holder of the product licence for this medicine is
Alliance Pharmaceuticals Ltd, Avonbridge House, Bath
Road, Chippenham, Wiltshire, SN15 2BB. The ampoules
are made by BCM Limited, 1 Thane Road, Nottingham,
What is Protirelin used for?
Protirelin is used mainly to assess the functioning of the
pituitary and thyroid glands. The test using this medicine can
help to identify certain medical conditions involving these
glands or, if you are already receiving treatment for such a
disorder, that the correct dose of medicine is being used. In
particular, Protirelin is used to test for overactivity of the
thyroid, including the condition known as Grave’s disease
which causes the eyeballs to protrude, underactivity of the
thyroid gland, underactivity of the pituitary gland and
diseases of the hypothalamus.
What should I tell the doctor before the test?
You should inform the doctor if you suffer from any of the
any other condition causing difficulty in breathing
any disorder of the pituitary gland
SUMMARY OF PRODUCT CHARACTERISTICS
You should also tell the doctor if you are taking any
medication (either prescribed or bought 'over the
counter'). A number of other medicines can interfere with
the results of this test, in particular the following:
• drugs which act on the thyroid gland
• oestrogens (such as are present in some contraceptive
• theophylline (a drug for asthma)
• levodopa and bromocriptine (for Parkinson’s disease)
• major tranquillisers of the phenothiazine group (such as
chlorpromazine), used for mental disorders
• metoclopramide (for nausea and vomiting)
• amiodarone (for disorders of the heart rhythm)
• carbamazepine (for epilepsy)
• lithium (for mental illness)
WOMEN: Please let the doctor know if you are pregnant.
Although no harmful effects on the unborn child are
known, the doctor may prefer to put off the test until after
the baby has been born. If you are breastfeeding, you may
notice extra swelling of the breasts and leaking of milk for
up to three days after the test.
How are Protirelin Ampoules used?
Please ensure that you follow any instructions given by your
doctor in preparation for the test (for example, not eating
A blood sample will be taken first so that the amount of
thyroid hormones in the blood can be measured. An
injection of Protirelin will then be given into a vein (the
normal adult dose is one ampoule or 200micrograms; a
lower dose of 1microgram per kilogram of bodyweight is
usually used in children) and another blood sample taken
thyroid hormones, levodopa, phenothiazines, salicylates, bromocriptine,
carbamazepine, lithium and by pharmacological doses of corticosteroids.
An increased response may be seen in subjects taking metoclopramide,
amiodarone or theophyllines and in men taking oestrogens. Over-treatment
with antithyroid drugs may also cause an enhanced response.
The ampoule solution should not be diluted.
NAME OF THE MEDICINAL PRODUCT
QUALITATIVE AND QUANTITATIVE COMPOSITION
Each ampoule contains 200micrograms of Protirelin (Thyrotrophin-releasing
hormone, TRH) in 2ml of solution.
Interpretation of results
Interpretation of the responses to Protirelin is based on the increase in TSH
and/or PBI, T3 or T4 levels from the basal values. In normal subjects, there is
a prompt rise in serum levels of TSH. The changes observed in various
conditions are briefly outlined below:
Solution for Injection
Children up to the age of 12
The procedures for administering Protirelin to children are identical to those
outlined above. An intravenous dose of 1µg/kg bodyweight may be used.
4.1 Therapeutic indications
The administration of Protirelin provides a means of assessing thyroid
function and the reserve of TSH in the pituitary gland and is recommended
as a test procedure where such assessment is indicated.
It is particularly useful as a diagnostic test for:
Ophthalmic Graves' disease
Mild or preclinical hypothyroidism
Hyperthyroidism - no rise in serum TSH or thyroid hormone levels.
Ophthalmic Graves' disease - often no rise in serum TSH or thyroid
Primary hypothyroidism - exaggerated and prolonged rise in serum TSH
but no change in thyroid hormone levels.
Hypopituitarism - absent or impaired TSH or thyroid hormone
response implies diminished TSH reserve.
Hypothalamic disease - a rise in serum TSH or thyroid hormone levels
can occur in the presence of hypothyroidism; delayed responses are
4.6 Pregnancy and lactation
Animal studies and clinical experience have shown no evidence of hazard in
human pregnancy at the recommended dosage. Nevertheless, the
established medical principle of not administering drugs during early
pregnancy should be observed.
Breast enlargement and leaking of milk have been reported following the
administration of protirelin to lactating women.
It may also be used in place of the T3 suppression test.
4.2 Posology and method of administration
There are no absolute contra-indications to Protirelin.
Protirelin ampoules are for intravenous injection.
Tests employing intravenous Protirelin are based on the serum TSH
response to a standard dose. They provide a means of both quantitative and
qualitative assessment of thyroid function. It is essential for each laboratory to
establish its own normal range of values for serum TSH before attempting
quantitative assessment of Protirelin responses by this means.
Intravenous Protirelin test
a) Blood sample taken for control TSH assay.
It is unlikely that you (or your child if he or she is having this
test) will experience any side-effects from the use of
Protirelin. If any do occur, they should be mild and of short
duration. The most likely are nausea, a desire to pass
water, a feeling of flushing, slight dizziness, a brief rise in
pulse rate and blood pressure and a peculiar taste.
If these do occur and you are concerned about them, or if
you think that Protirelin has caused any other side-effect,
please tell your doctor or nurse about it.
If you are having tests carried out to assess the function of
your pituitary gland and being treated with Protirelin there
is a very small risk that the tests can cause a condition called
pituitary apoplexy. This condition only develops in patients
who have a rare type of brain tumour (called a pituitary
macroadenoma) and is caused by a sudden swelling of the
tumour which may need to be treated surgically. If you
develop a sudden headache behind your eyes, severe
nausea or problems with your vision, please tell your
doctor straight away.
This medicine should not be used after the expiry date
that is shown on the carton.
All medicines should be kept out of the reach of children.
Date of preparation of this leaflet: August 2010
6.1 List of excipients
Glacial acetic acid
Water for Injections
6.3 Shelf life
6.4 Special precautions for storage
The recommended maximum storage temperature is 30°C.
4.7 Effects on ability to drive and use machines
4.8 Undesirable effects
Protirelin is well tolerated. Following rapid intravenous injection, side-effects
of a mild and transient nature may be experienced. These comprise nausea,
a desire to micturate, a feeling of flushing, slight dizziness and a peculiar taste,
and have been attributed to a local action of the bolus of Protirelin on the
muscle of the gastro-intestinal and genito-urinary tracts. A transient increase
in pulse rate and blood pressure may also be noted.
Pituitary apoplexy requiring acute neurosurgical intervention has been
reported infrequently for patients with pituitary macroadenomas following
the acute administration of protirelin injection.
6.5 Nature and contents of container
Clear glass ampoules coded with orange and black colour rings each
containing 2ml of solution, in packs of 10 ampoules.
6.6 Special precautions for disposal
MARKETING AUTHORISATION HOLDER
Alliance Pharmaceuticals Ltd
MARKETING AUTHORISATION NUMBER(S)
DATE OF FIRST AUTHORISATION/RENEWAL OF THE
No symptoms of overdosage have been noted in patients receiving up to
The Protirelin test provides, in most instances, information similar to that
obtained from a T3 suppression test in that an absent or impaired response
usually correlates with an absent or impaired response to T3 suppression.
b) Protirelin 200µg given as a single bolus injection.
c) Blood sample taken 20 minutes after injection for peak TSH assay.
d) If necessary, a further blood sample may be taken 60 minutes after
injection to detect a delayed TSH response.
The use of Protirelin in the elderly has been well documented. Dosage
requirements and the side-effects are similar to those of younger adults. The
response may be decreased in elderly subjects, but this does not interfere
with the interpretation of the test results.
twenty minutes later. A further sample may be taken an
hour after the injection if necessary.
5.1 Pharmacodynamic properties
Pharmacotherapeutic group: V04CJ.
Protirelin stimulates the secretion of thyroid stimulating hormone (TSH).
Intravenous injection results in a prompt rise in serum TSH levels in normal
subjects, peak levels being observed about twenty minutes after
administration. There is a concomitant rise in serum levels of prolactin.
4.4 Special warnings and precautions for use
In view of the postulated effect of bolus injections of Protirelin on smooth
muscle, patients with bronchial asthma or other types of obstructive airways
disease should be closely monitored. Caution should always be observed in
patients with myocardial ischaemia and severe hypopituitarism.
4.5 Interaction with other medicinal products and other forms of interaction
The secretion of thyrotrophin appears to be modulated by dopaminergic and
noradrenergic pathways. The TSH response to Protirelin may be reduced by
10 DATE OF REVISION OF THE TEXT
5.2 Pharmacokinetic properties
TSH rapidly disappears from the plasma after intravenous injection. Over
90% is removed within 20 minutes with a half life of about 5.3 minutes.
About 5.5% of the dose is excreted in the urine, mostly within 30 minutes.
5.3 Preclinical safety data
There are no pre-clinical data of relevance to the prescriber which are
additional to that already included in other sections of the SPC.