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Firmagon Side Effects

Generic Name: degarelix

Note: This page contains information about the side effects of degarelix. Some of the dosage forms included on this document may not apply to the brand name Firmagon.

For the Consumer

Applies to degarelix: subcutaneous powder for solution

In addition to its needed effects, some unwanted effects may be caused by degarelix (the active ingredient contained in Firmagon). In the event that any of these side effects do occur, they may require medical attention.

If any of the following side effects occur while taking degarelix, check with your doctor or nurse immediately:

More common:
  • Back pain
  • blurred vision
  • dizziness
  • fever
  • flushing or redness of the skin
  • hard lump
  • headache
  • nervousness
  • pain
  • pounding in the ears
  • slow or fast heartbeat
  • small lumps under the skin
  • swelling
  • unusually warm skin
Less common:
  • Bladder pain
  • bloody or cloudy urine
  • chills
  • decrease in testicle size
  • decreased interest in sexual intercourse
  • difficult, burning, or painful urination
  • difficulty in moving
  • frequent urge to urinate
  • inability to have or keep an erection
  • increased sweating
  • loss in sexual ability, desire, drive, or performance
  • lower back or side pain
  • muscle pain or stiffness
  • pain in the joints
  • Chest pain or discomfort
  • fainting
  • irregular heartbeat
  • pounding heartbeat
  • shortness of breath

Minor Side Effects

Some of the side effects that can occur with degarelix may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Difficulty having a bowel movement (stool)
  • feeling of warmth
  • increased weight
  • redness of the face, neck, arms, and occasionally, upper chest
  • sudden sweating
  • unusual tiredness or weakness
Less common:
  • Diarrhea
  • lack or loss of strength
  • nausea
  • night sweats
  • sleeplessness
  • swelling of the breasts or breast soreness
  • trouble sleeping
  • unable to sleep

For Healthcare Professionals

Applies to degarelix: subcutaneous powder for injection


Endocrine side effects have included hot flashes, increased weight, and fatigue.[Ref]


Local side effects have included injection site reactions (e.g. pain, erythema, swelling or induration).[Ref]


Musculoskeletal side effects have included back pain and arthralgia.[Ref]


Cardiovascular side effects have included hypertension.[Ref]


Gastrointestinal side effects have included constipation.[Ref]


Genitourinary side effects have included urinary tract infection.[Ref]


Hypersensitivity reactions have included postmarketing reports of anaphylaxis, urticaria, and angioedema.[Ref]


1. "Product Information. Firmagon (degarelix)." Ferring Pharmaceuticals Inc, Tarrytown, NY.

2. "Multum Information Services, Inc. Expert Review Panel"

Not all side effects for Firmagon may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.