Trelstar (triptorelin pamoate) is a prescription drug that’s used to treat advanced prostate cancer. The drug is injected into a muscle by a healthcare professional. Your dosage schedule depends on the specific dose of Trelstar you’re prescribed.

Trelstar is used for palliative treatment of advanced prostate cancer in adult males.* Advanced cancer means the cancer has spread outside the prostate to other organs. With palliative treatment, symptoms of your condition are reduced to help improve your quality of life. Trelstar isn’t meant to cure prostate cancer.

The active ingredient in Trelstar is triptorelin. Trelstar belongs to a group of drugs called gonadotropin releasing hormone (GnRH) agonists.

This article describes the dosages of Trelstar, as well as its strengths and how it’s given. To learn more about Trelstar uses, side effects, Trelstar cost, how it works and more, see this in-depth article.

Note: Trelstar Depot was a brand-name version of Trelstar that is no longer available.

* Sex and gender exist on spectrums. Use of the terms “male” in this article refers to sex assigned at birth.

This section describes the usual dosages of Trelstar. Keep reading to learn more.

What is Trelstar’s form?

Trelstar is available as a powder that’s mixed with sterile water to make a liquid suspension. Trelstar is given as an intramuscular injection by a healthcare professional.

What strengths does Trelstar come in?

Trelstar comes in three strengths:

  • 3.75 milligrams (mg)
  • 11.25 mg
  • 22.5 mg

What are the usual dosages of Trelstar?

The information below describes dosages that are commonly used or recommended. Your doctor will determine the best dosage to fit your needs. In some cases, doctors may adjust your dosage from those shown below.

Dosage for advanced prostate cancer

Trelstar is used to treat advanced prostate cancer in adult males. Your dosing schedule depends on the dose your doctor prescribes:

Trelstar doseDosing schedule
3.75 mgonce every 4 weeks
11.25 mgonce every 12 weeks
22.5 mgonce every 24 weeks

The doses and dosing schedules aren’t interchangeable. Your doctor will discuss the best dosage and dosing schedule that fits your needs.

If you have questions about your dosage or how you’ll receive Trelstar, talk with your doctor.

Trelstar is given as an intramuscular injection into either buttock. It’s given by a healthcare professional.

You’ll be given your Trelstar injection at your doctor’s office or healthcare facility.

Is Trelstar used long term?

Yes, Trelstar is typically used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely receive it long term.

Your doctor will discuss your treatment schedule and how long you’re likely to receive Trelstar.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.