Fulvestrant Dosage

Medically reviewed by Drugs.com. Last updated on Mar 20, 2025.

Usual Adult Dose for Breast Cancer

MONOTHERAPY: 500 mg IM into the buttocks (gluteal area) slowly (1 to 2 minutes per injection) as two 5 mL injections, one in each buttock, on days 1, 15, 29 and once monthly thereafter

COMBINATION THERAPY: In combination with palbociclib, or abemaciclib, or ribociclib: 500 mg IM into the buttocks (gluteal area) slowly (1 to 2 minutes per injection) as two 5 mL injections, one in each buttock, on days 1, 15, 29 and once monthly thereafter.

• The recommended dose of palbociclib is a 125 mg orally once a day for 21 days followed by 7 days off for a cycle of 28 days.
• The recommended dose of abemaciclib is 150 mg orally 2 times a day.
• The recommended dose of ribociclib is 600 mg once a day for 21 days followed by 7 days off for a cycle of 28 days.

Comments:

• This drug is not recommended for use in men.
• When this drug is used in combination with palbociclib, the recommended dose of palbociclib is 125 mg orally once daily for 21 consecutive days followed by 7 days off therapy for a complete cycle of 28 days. Palbociclib should be taken with food. Refer to the prescribing information for palbociclib.
• When this drug is used in combination with abemaciclib, the recommended dose of abemaciclib is 150 mg orally 2 times a day. Abemaciclib may be taken with or without food. Refer to the prescribing information for abemaciclib.
• Pre- or peri-menopausal women treated with the combination of this drug plus palbociclib or abemaciclib should be treated with luteinizing hormone-releasing hormone (LHRH) agonists according to current guidelines.

Uses:
Monotherapy:

• For hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer in postmenopausal women not previously treated with endocrine therapy

OR

• For HR-positive advanced breast cancer in postmenopausal women with disease progression following endocrine therapy.

Combination Therapy:

• For HR-positive, HER2-negative advanced or metastatic breast cancer in postmenopausal women in combination with ribociclib as initial endocrine based therapy or following disease progression on endocrine therapy

OR

• For HR-positive, HER2-negative advanced or metastatic breast cancer in combination with palbociclib or abemaciclib in women with disease progression after endocrine therapy

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Moderate hepatic impairment (Child-Pugh B): 250 mg IM into the buttock (gluteal area) slowly (1 to 2 minutes) as one 5 mL injection on days 1, 15, 29 and once monthly thereafter
Severe hepatic impairment (Child-Pugh C): Data not available

Precautions

CONTRAINDICATIONS:

• Hypersensitivity to the active component or any of the ingredients

Safety and efficacy have not been established in patients younger than 18 years.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration/preparation techniques:

• Administer the injection according to the local guidelines for performing large volume IM injections.
• Due to the proximity of the underlying sciatic nerve, caution should be taken if administering this drug at the dorsogluteal injection.
• Palbociclib should be taken with food. Refer to the full prescribing information for palbociclib.
• Abemaciclib may be taken with or without food. Refer to the Full Prescribing -Ribociclib can be taken with or without food. Refer to the full prescribing information for ribociclib.
• Remove glass syringe barrel from tray and check that it is not damaged.
• Remove perforated patient record label from syringe.
• Inspect drug product in glass syringe for any visible particulate matter or discoloration prior to use. Discard if particulate matter or discoloration is present.
• Peel open the safety needle outer packaging.
• Hold the syringe upright on the ribbed part. With the other hand, take hold of the cap and carefully tilt cap back and forth (DO NOT TWIST CAP) until the cap disconnects for removal.
• Pull the cap off in a straight upward direction. DO NOT TOUCH THE STERILE SYRINGE TIP.
• Attach the safety needle to the syringe tip (Luer-Lok). Twist needle until firmly seated. Confirm that the needle is locked to the Luer connector before moving or tilting the syringe out of the vertical plane to avoid spillage of syringe contents.
• Pull shield straight off needle to avoid damaging needle point.
• Remove needle sheath.
• Expel excess gas from the syringe (a small gas bubble may remain).
• Administer IM slowly (1 to 2 minutes/injection) into the buttock (gluteal area).
• After injection, immediately activate the lever arm to deploy the needle shielding by applying a single-finger stroke to the activation assisted lever arm to push the lever arm completely forward. Listen for a click. Confirm that the needle shielding has completely covered the needle.
• Discard the empty single use syringe into an approved sharps collector in accordance with applicable regulations and institutional policy.

Storage requirements:

• Refrigerate at 2C to 8 C (36F to 46F).
• Store in the original carton until time of use.
• Protect from light.

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See also:

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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