Filgrastim
Brand name Neupogen
Used in the following combined preparations None
GENERAL INFORMATION
Filgrastim is a synthetic form of G-CSF graranulocyte-colony stimulating factor), a naturally occurring protein responsible for the manufacture of white blood cells. Deficiency of G-CSF increases the risk of bacterial infection. The drug works by stimulating bone marrow to produce white blood cells, thus reducing the risk of infection. It also causes bone marrow cells to move into the bloodstream, where they can be collected to use in the treatment of bone marrow disease, or to replace bone marrow lost during intensive cancer treatment.
Filgrastim is used to treat patients with congenital neutropenia (deficiency of G-CSF from birth), some AIDS patients, and those who have recently received high doses of chemo- or radiotherapy during bone-marrow transplantation or cancer treatment. Such patients are prone to frequent and severe infections.
Bone pain is a common adverse effect of filgrastim treatment, but can be controlled using painkillers. There is an increased risk of leukaemia if filgrastim is given to patients with certain rare blood disorders.
INFORMATION FOR USERS
Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.
How taken
Injection.
Frequency and timing of doses
Once daily.
Adult dosage range
5-12mcg/kg body weight, depending upon condition being treated and response.
Onset of effect
24 hours (increase); several weeks (recovery of normal numbers).
Duration of action
Approximately 2 days.
Diet advice
None.
Storage
Store in a refrigerator out of the reach of children.
Missed dose
Take as soon as you remember. If your next dose is due within 6 hours, do not take the missed dose. Take the next scheduled dose as usual.
Stopping the drug
Do not stop taking the drug without consulting your doctor; stopping the drug may lead to worsening of the underlying condition.
Exceeding the dose
An occasional unintentional extra dose is unlikely to cause problems. But if you notice any unusual symptoms or if a large overdose has been taken, notify your doctor.
POSSIBLE ADVERSE EFFECTS
Adverse effects resulting from short courses of filgrastim are unusual. Most common is bone pain, which is probably linked to the stimulant effect of the drug on bone marrow.
INTERACTIONS
Cytotoxic chemotherapy or radiotherapy should not be administered within 24 hours of taking filgrastim because of the risk of increasing the damage these treatments inflict on the bone marrow.
QUICK REFERENCE
Drug group Blood stimulant
Overdose danger rating Medium
Dependence rating High
Prescription needed Yes
Available as generic No
SPECIAL PRECAUTIONS
Be sure to tell your doctor if:
You suffer from any blood disorders.
You are taking other medications.
Pregnancy
Safety in pregnancy not established. Discuss with your doctor.
Breast-feeding
Safety in breast-feeding not established. Discuss with your doctor.
Infants and children
No special problems.
Over 60
No special problems.
Driving and hazardous work
No known problems.
Alcohol
No known problems.
PROLONGED USE
Prolonged use may lead to a slightly increased risk of certain leukaemias. Cutaneous vaculitis (inflammation of blood vessels of the skin), osteoporosis (weakening of the bones), hair thinning, enlargement of the spleen and liver, and bleeding due to reduction in platelet numbers may also occur.
Monitoring
Blood checks and regular physical examinations are performed, as well as X-rays or bone scans to check for bone thinning.
