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| Filgrastim Injection(Human
granulocyte colony stimulating factor) |
What is Granulocyte? |
Granulocytes are a category of
white blood cells characterised by the presence of
granules in their cytoplasm. They are also called
polymorphonuclear leukocytes (PMN or PML) because of
the varying shapes of the nucleus, which is usually
lobed into three segments. In common parlance, the
term polymorphonuclear leukocyte often refers
specifically to neutrophil granulocytes, the most
abundant of the granulocytes.
Granulocytes or PMN
are released from the bone marrow by the regulatory
complement proteins.
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| Classification |
There are three types of
granulocytes, distinguished by their appearance
under Wright's stain:
►Neutrophil granulocytes
(a type of blood cell needed to fight infection)
►Eosinophil granulocytes
►Basophil granulocytes
Their names are derived from their staining
characteristics; for example, the most abundant
granulocyte is the neutrophil granulocyte, which has
neutrally-staining cytoplasmic granules.
Other white blood cells which are not granulocytes
("agranulocytes") are mainly lymphocytes and
monocytes.
Toxic materials produced or released
Examples of toxic materials produced or released by
degranulation by granulocytes on the ingestion of
microorganism includes:
►Low pH vesicles (3.5-4.0)
►Toxic
oxygen-derived products (e.g. superoxide,
hydrogen peroxide, hydroxy radicals, singlet oxygen,
hypohalite)
►Toxic nitrogen oxides (nitric oxide)
►Antimicrobial agents
(Defensins and cationic
proteins)
►Enzymes
►Lysozyme: dissolves cell walls of some gram positive
bacteria
►Acid hydrolases: further digest bacteria
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What is Filgrastim? |
Filgrastim is a
granulocyte colony-stimulating factor (G-CSF) analog
used to stimulate the proliferation and
differentiation of granulocytes. It is produced by
recombinant DNA technology. The gene for human
granulocyte colony-stimulating factor is inserted
into the genetic material of Escherichia coli.
The
G-CSF then produced by E. coli is only slightly
different from G-CSF naturally made in humans.
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Why is this medication
prescribed? |
Filgrastim is used to
decrease the chance of infection in people who have
certain types of cancer and are receiving
chemotherapy medications that may decrease the
number of neutrophils, in people who are undergoing
bone marrow transplants, and in people who have
severe chronic neutropenia (condition in which there
are a low number of neutrophils in the blood).
Filgrastim is also used to prepare the blood for
leukapheresis.
Filgrastim is in a
class of medications called colony-stimulating
factors. It works by helping the body make more
neutrophils.
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How should this
medicine be used? |
Filgrastim comes as
a solution (liquid) to inject under the skin or into
a vein. It is usually given once a day, but may be
given twice a day when it is used to treat
severe chronic neutropenia. The length of your treatment
depends on the condition that you have and how well
your body responds to the medication. If you are
using filgrastim to decrease the risk of infection
during chemotherapy, you will receive your first
dose of filgrastim at least 24 hours after you
receive a dose of chemotherapy, and will continue to
receive the medication every day for up to 2 weeks.
If you are using filgrastim to decrease the risk of
infection during a bone marrow transplant, you will
receive the medication at least 24 hours after you
receive chemotherapy and at least 24 hours after the
bone marrow is infused. If you are using filgrastim
to prepare your blood for leukapheresis, you will
receive your first dose of filgrastim at least 4
days before the first leukapheresis and will
continue to receive the medication until the last
leukapheresis. If you are using filgrastim to treat
severe chronic neutropenia, you may need to use the
medication for a long period of time.
Filgrastim may be given to you by a nurse or other
healthcare provider, or you may be told to inject
the medication at home. If you will be injecting
filgrastim at home, inject the medication at about
the same time every day. Follow the directions on
your prescription label carefully, and ask your
doctor or pharmacist to explain any part you do not
understand. Use filgrastim exactly as directed. Do
not use more or less of it or use it more often than
prescribed by your doctor.
If you will be injecting filgrastim yourself, a
health care provider will show you how to inject the
medication. Be sure that you understand these
directions. Ask your health care provider if you
have any questions about where on your body you
should inject filgrastim, how to give the injection,
what type of syringe to use, or how to dispose of
used needles and syringes after you inject the
medication.
Your doctor may start you on a low dose of
filgrastim and gradually increase your dose. Your
doctor may also decrease your dose, depending on how
your body reacts to the medication.
If you are using filgrastim to treat severe chronic
neutropenia, you should know that filgrastim will
control your condition but will not cure it.
Continue to take filgrastim even if you feel well.
Do not stop taking filgrastim without talking to
your doctor.
Ask your pharmacist or doctor for a copy of the
manufacturer's information for the patient.
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Other uses for this
medicine |
Filgrastim is also used
to decrease the chance of infection in people who
have human
immunodeficiency virus (HIV) or people
who are taking certain medications that decrease the
number of neutrophils. Talk to your doctor about the
risks of using this medication for your condition.
This medication may be prescribed for other uses;
ask your doctor or pharmacist for more information. |
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What special
precautions should the patient follow? |
Before using
filgrastim:
►Tell your doctor and
pharmacist if you are allergic to filgrastim,
pegfilgrastim (Neulasta)>
►Medications
made from E. coli bacteria, or any other
medications. Ask your pharmacist if you do not know
if a medication you are allergic to is made from E.
coli bacteria.
►Tell your doctor if you or the
person who will be injecting filgrastim for you is
allergic to latex.
►Tell your doctor and pharmacist what prescription
and nonprescription medications,
vitamins,
nutritional supplements, and herbal products you are
taking or plan to take. Be sure to mention lithium
(Eskalith, Lithobid). Your doctor may need to change
the doses of your medications or monitor you
carefully for side effects.
►Tell your doctor if you are being treated with
radiation therapy and if you have or have ever had
chronic myeloid leukemia ,
myelodysplasia ,
or an
enlarged spleen
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►Tell your doctor if you have
sickle cell disease. If you have sickle cell
disease, you may be more likely to have a crisis
during your treatment with filgrastim. Drink plenty
of fluids during your treatment with filgrastim and
call your doctor right away if you have a sickle
cell crisis during your treatment.
►Tell your doctor if you are pregnant, plan to become
pregnant, or are breast-feeding. If you become
pregnant while using filgrastim, call your doctor.
►If you are having surgery, including dental surgery,
tell the doctor or dentist that you are using
filgrastim.
you should know that filgrastim decreases the risk
of infection, but does not prevent all infections
that may develop during or after chemotherapy. Call
your doctor if you develop signs of infection such
as fever; chills;
rash; sore throat;
diarrhea; or
redness, swelling, or pain around a cut or sore.
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| What special dietary
instructions should I follow? |
Unless your doctor tells you otherwise, continue
your normal diet.
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What should I do if I
forget a dose? |
| If you will be
injecting filgrastim at home, talk to your doctor
about what you should do if you forget to inject the
medication on schedule. |
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