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Fulvestrant parenteral

Updated 2 Feb 2023 | Breast cancer


Injections of fulvestrant.

Drugs List

  • FASLODEX 250mg/5ml solution for injection pre-filled syringe
  • fulvestrant 250mg/5ml solution for injection pre-filled syringe
  • Therapeutic Indications


    Hormone receptor +ve, HER2 -ve locally advanced or metastatic breast cancer
    Hormone-dependent metastatic breast cancer in postmenopausal patients

    Oestrogen receptor positive, locally advanced or metastatic breast cancer in post menopausal women not treated previously with endocrine treatment.

    Oestrogen receptor positive, locally advanced or metastatic breast cancer in post menopausal women where disease has relapsed during or after anti-oestrogen treatment or disease progression while on anti-oestrogen treatment.

    Adjunctive treatment with palbociclib in hormone receptor positive, human epidermal growth factor receptor 2 negative, locally advanced or metastatic breast cancer in women who have received prior endocrine treatment.
    When fulvestrant with palbociclib are given in combination in pre or peri-menopausal women, combine with luteinising hormone releasing hormone agonist.


    Whilst the doses stated below are those recommended by the manufacturer, local cancer network protocols for the relevant indication should be consulted.


    The recommended dose is 500mg fulvestrant at intervals of one month, with an additional 500mg dose given two weeks after the initial dose.


    Two consecutive 5ml slow intramuscular injections (1-2 minutes/injection) one into each buttock.
    Use caution if injecting at the dorsogluteal site due to the proximity of the underlying sciatic nerve.


    Children under 18 years
    Hypersensitivity to benzyl alcohol
    Severe hepatic impairment

    Precautions and Warnings

    Haemorrhagic diathesis
    Predisposition to thromboembolic disease
    Epileptic disorder
    Hepatic impairment
    History of alcohol abuse
    Renal impairment - creatinine clearance below 30 ml/minute

    Advise ability to drive/operate machinery may be affected by side effects
    Contains benzyl alcohol
    Caution injecting at dorsogluteal site due to proximity of sciatic nerve
    Potential risk of osteoporosis
    Female: Ensure adequate contraception during treatment

    Caution should be used when treating patients with bleeding diatheses, thrombocytopenia or those taking concurrent anti-coagulants because of the route of administration (deep intramuscular injection into the buttock).

    The efficacy and safety of fulvestrant in patients with critical visceral disease (as either monotherapy or in combination with palbociclib) has not been studied.

    Pregnancy and Lactation


    Fulvestrant is contraindicated during pregnancy.

    The manufacturer recommends that fulvestrant is contraindicated during pregnancy. In animal studies, fulvestrant has been shown to cross the placenta and has shown reproductive toxicity, including an increased incidence of foetal abnormalities and death. If pregnancy occurs during treatment, the patient must be informed of the potential hazard to the foetus and the potential risk for loss of pregnancy.


    Fulvestrant is contraindicated during breastfeeding.

    The manufacturer reccomends that breastfeeding must be discontinued during treatment with fulvestrant. It is not known whether fulvestrant is excreted in human breast milk but animal studies have shown that it is excreted into the milk of rats. Due to the potential for serious adverse reactions in a nursing infant, fulvestrant is contraindicated while breastfeeding.

    Side Effects

    Anaphylactic reaction
    Back pain
    Gamma glutamyl transferase (GGT) increased
    Genital moniliasis
    Haematoma (injection site)
    Haemorrhage (injection site)
    Hepatic failure
    Hot flushes
    Hypersensitivity reactions
    Increase in alkaline phosphatase
    Increase in serum ALT/AST
    Injection site reactions
    Joint pain
    Musculoskeletal pain
    Peripheral neuropathy
    Reduced platelet count
    Serum bilirubin increased
    Urinary tract infections
    Vaginal haemorrhage
    Venous thrombosis

    Effects on Laboratory Tests

    Fulvestrant may cause falsely elevated estradiol results in assays. The similar chemical structure to estradiol means it may cross-react with the antibodies used in immunoassays.


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: February 2021

    Reference Sources

    Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. Accessed on 9 February 2021.

    Summary of Product Characteristics: Faslodex 250 mg solution for injection. AstraZeneca UK Limited. Revised April 2020.

    Summary of Product Characteristics: Fulvestrant Dr. Reddy's 250mg Solution for Injection in Pre-Filled Syringe. Dr. Reddy's Laboratories (UK) Ltd. Revised March 2020.

    Summary of Product Characteristics: Fulvestrant Teva 250mg Solution for Injection in Pre-Filled Syringe. Teva UK Limited. Revised April 2018.

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