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URL of this page: https://medlineplus.gov/druginfo/meds/a611047.html

Triptorelin Injection

pronounced as (trip'' toe rel' in)

Why is this medication prescribed?

Triptorelin injection (Trelstar) is used to treat the symptoms associated with advanced prostate cancer. Triptorelin injection (Triptodur) is used to treat central precocious puberty (CPP; a condition causing children to enter puberty too soon, resulting in faster than normal bone growth and development of sexual characteristics) in children 2 years and older. Triptorelin injection is in a class of medications called gonadotropin-releasing hormone (GnRH) agonists. It works by decreasing the amount of certain hormones in the body.

How should this medicine be used?

Triptorelin injection (Trelstar) comes as an extended-release (long-acting) suspension to be injected into the muscle of either buttock by a doctor or nurse in a medical office or clinic. Triptorelin injection (Trelstar) also comes as an extended-release suspension to be injected into the muscle of the buttock or thigh by a doctor or nurse in a medical office or clinic. When used for prostate cancer, an injection of 3.75 mg of triptorelin (Trelstar) is usually given every 4 weeks, an injection of 11.25 mg of triptorelin (Trelstar) is usually given every 12 weeks, or an injection of 22.5 mg of triptorelin (Trelstar) is usually given every 24 weeks. When used in children with central precocious puberty, an injection of 22.5 mg of triptorelin (Triptodur) is usually given every 24 weeks.

Triptorelin may cause an increase in certain hormones in the first few weeks after injection. Your doctor will monitor you carefully for any new or worsening symptoms during this time.

Triptorelin may cause metabolic changes that lead to long-term conditions like diabetes, hyperlipidemia and, non-alcoholic liver disease. Your doctor will monitor your symptoms and labs during treatment for the development of any of these conditions. Discuss with your doctor any concerns you have about the long-term effects of using triptorelin.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before receiving triptorelin injection,

  • tell your doctor and pharmacist if you are allergic to triptorelin, goserelin (Zoladex), histrelin (Supprelin LA, Vantas), leuprolide (Eligard, Lupron), nafarelin (Synarel), any other medications, or any of the ingredients in triptorelin injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
  • tell your doctor if you or anyone in your family has ever had long QT syndrome (condition that increases the risk of developing an irregular heartbeat that may cause fainting or sudden death). Also tell your doctor if you have or have ever had diabetes; cancer that has spread to the spine (backbone),; urinary obstruction (blockage that causes difficulty urinating), a low level of potassium, calcium, or magnesium in your blood, a heart attack; heart failure; a mental illness; a seizure or epilepsy; a stroke, mini-stroke, or other brain problems; a brain tumor; or heart, kidney, or liver disease.
  • you should know that triptorelin is not to be used in women who are pregnant or who can become pregnant. Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you think you have become pregnant while using triptorelin injection, call your doctor immediately. Triptorelin injection can harm the fetus.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What side effects can this medication cause?

Triptorelin injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • heartburn
  • constipation
  • hot flashes (a sudden wave of mild or intense body heat), sweating, or clamminess
  • decreased sexual ability or desire
  • mood changes such as crying, irritability, impatience, anger, and aggression
  • leg or joint pain
  • breast pain
  • depression
  • pain, itching, swelling, or redness at the place where injection was given
  • difficulty falling asleep or staying asleep
  • cough

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • hives
  • rash
  • itching
  • difficulty breathing or swallowing
  • swelling of the face, eyes, mouth, throat, tongue, or lips
  • hoarseness
  • seizures
  • chest pain
  • pain in the arms, back, neck, or jaw
  • slow or difficult speech
  • dizziness or fainting
  • weakness or numbness of an arm or leg
  • not able to move legs
  • bone pain
  • painful or difficult urination
  • blood in urine
  • frequent urination
  • extreme thirst
  • weakness
  • blurred vision
  • dry mouth
  • nausea
  • vomiting
  • breath that smells fruity
  • decreased consciousness

In children receiving triptorelin injection (Triptodur) for central precocious puberty, new or worsening symptoms of sexual development may occur during the first few weeks of treatment. In girls, the onset of menstruation or spotting (light vaginal bleeding) may occur during the first two months of this treatment. If bleeding continues beyond the second month, call your doctor.

Triptorelin injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests and take certain body measurements to check your body's response to triptorelin injection. Your blood sugar and glycosylated hemoglobin (HbA1c) should be checked regularly.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving triptorelin injection.

Ask your pharmacist any questions you have about triptorelin injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Trelstar®
  • Triptodur®
Last Revised - 01/15/2024