Important Safety Information - Kyzatrex® (testosterone undecanoate)

What is this?

This Important Safety Information summarizes the most important warnings and precautions for Kyzatrex® (testosterone undecanoate), an FDA-approved oral testosterone capsule prescribed for adult males with testosterone deficiency (hypogonadism). It does not contain all possible information. Always read your prescription label and follow your healthcare provider’s instructions.

Controlled Substance Information

Kyzatrex® is a Schedule III (CIII) controlled substance because it contains testosterone, which can be a target for misuse. Keep this medication in a safe place and never give it to anyone else, even if they have similar symptoms—sharing or selling it is against the law and can cause serious harm.

Misuse of testosterone, particularly at higher-than-prescribed doses or combined with other anabolic-androgenic steroids, can cause serious heart and mental health effects. Your healthcare provider may screen you for signs of misuse before and during treatment.

Most Serious Warnings

Kyzatrex® can cause:

  • Increased blood pressure, which can raise cardiovascular risk (including heart attack and stroke) over time. Your provider will monitor your blood pressure, and Kyzatrex® is not recommended if you have high blood pressure that isn’t controlled. A large clinical trial (TRAVERSE) of a different testosterone formulation (topical gel) found no increase in these events in men treated for low testosterone compared with placebo, but your provider will still keep an eye on your heart health.

  • Polycythemia (a significant rise in red blood cell count; hematocrit of 54% or greater), which increases the risk of blood clots, stroke, and heart attack.

  • Blood clots in the legs or lungs (deep vein thrombosis, pulmonary embolism).

  • Worsening of sleep apnea, particularly in patients with obesity or chronic lung conditions.

  • Prostate growth or worsening of a pre-existing prostate condition. Testosterone can also stimulate hormone-sensitive cancers such as prostate or breast cancer.

Seek medical help right away if you develop symptoms of any of these.

Who Should NOT Take Kyzatrex®

Do not take Kyzatrex® if you:

  • Have known or suspected prostate or breast cancer

  • Are allergic to Kyzatrex® or any of its ingredients

  • Have low testosterone due to aging alone (Kyzatrex® is not approved for age-related low testosterone)

  • Have serious heart problems, such as unstable angina, a very recent heart attack, or congestive heart failure

  • Have polycythemia vera or a hematocrit of 54% or greater

  • Have a condition that makes your blood clot too easily, such as Factor V Leiden, protein C or S deficiency, antithrombin deficiency, a prothrombin gene mutation, sickle cell anemia, antiphospholipid syndrome, or paroxysmal nocturnal hemoglobinuria

  • Have an active, untreated pituitary or adrenal condition that hasn’t been evaluated by a specialist

  • Are using anabolic steroids or have used them within the past 6 months

Before Using Kyzatrex®, Tell Your Healthcare Provider if You:

  • Have a history of heart disease, stroke, or cardiovascular procedures

  • Have high blood pressure or are taking blood pressure medications

  • Have been diagnosed with sleep apnea or have been told you snore heavily

  • Have diabetes or take insulin or blood sugar medications

  • Have prostate conditions, including an elevated PSA or BPH (enlarged prostate)

  • Have blood clots or a personal or family history of blood clots

  • Have a condition that can raise your red blood cell count, such as polycythemia vera

  • Have liver or kidney conditions

  • Have a history of cancer, especially hormone-sensitive cancers such as prostate or breast cancer

  • Have abnormal hematocrit or red blood cell lab results

  • Have any eye problems or previous episodes of vision changes beyond minor issues

  • Are taking anticoagulants (blood thinners) such as warfarin

  • Are taking corticosteroids

  • Are taking any medications that affect hormone levels (e.g., other androgens, clomiphene, hCG, or aromatase inhibitors)

  • Are taking medications that can raise blood pressure, such as some cold or pain medicines

  • May want to have children in the future (testosterone suppresses sperm production — see “Fertility”)

Possible Side Effects

Common:

  • Increased blood pressure

  • Changes in cholesterol and triglycerides. In clinical trials, patients taking Kyzatrex® had reductions in lipid levels, including total cholesterol, LDL cholesterol, HDL ("good") cholesterol, and triglycerides. Changes may require adjusting your cholesterol medication, if you take it, or stopping testosterone therapy.

  • Increased hematocrit (red blood cell count)

  • Acne or oily skin

  • Increased PSA

  • Headache

  • Diarrhea, nausea, or constipation

  • Mood changes, irritability, or anxiety

  • Fatigue

  • Joint or back pain

  • Swelling of the legs (fluid retention)

  • Breast tenderness or enlargement (gynecomastia)

  • Fertility changes, including smaller testicles and lower sperm count

  • Increased or decreased libido

Serious (seek medical care immediately):

  • Signs of blood clots (leg swelling or pain, chest pain, shortness of breath, sudden vision changes, difficulty speaking)

  • Signs of stroke (sudden weakness or numbness, severe headache, confusion, vision or speech changes)

  • Difficulty breathing during sleep or worsening snoring

  • A severe or sudden increase in blood pressure

  • Signs of liver problems (yellowing of the skin or eyes, dark urine, belly pain) — rare with Kyzatrex®, which is absorbed through the lymphatic system and largely bypasses the liver, unlike older oral steroids

  • New or worsening urinary symptoms (difficulty urinating, weak urine stream)

  • Signs of a serious allergic reaction (hives, swelling of the face/lips/throat, difficulty breathing)

While Using Kyzatrex®

Tell your healthcare provider right away if you:

  • Start any new medication, especially blood thinners, insulin, corticosteroids, 5-alpha reductase inhibitors (finasteride or dutasteride, which can also lower your PSA reading), or other hormone-modifying medications

  • Are diagnosed with a new medical condition, including prostate or cardiovascular conditions

  • Experience changes in mood, sleep, or energy that concern you

  • Develop signs of a blood clot (leg swelling or pain, chest pain, shortness of breath), stroke (sudden weakness, numbness, confusion, or vision or speech changes), liver problems (yellowing of the skin or eyes, dark urine, belly pain), a serious allergic reaction, or new or worsening urinary symptoms

  • Have diabetes and notice low blood sugar or trouble keeping your blood sugar in your target range — Kyzatrex® can lower blood glucose and reduce how much insulin or other diabetes medication you need, so share your readings with the healthcare provider managing your diabetes

  • Miss doses consistently or notice reduced effectiveness over time

Fertility

  • Testosterone suppresses sperm production and may reduce fertility during treatment. For many men this is reversible after stopping, but recovery is not guaranteed.

  • If you are trying to conceive, discuss this with your healthcare provider before starting. Kyzatrex® is not appropriate for patients whose primary goal is to preserve or restore fertility.

  • Women who are or may become pregnant should not handle or take Kyzatrex®; testosterone can harm an unborn baby.

These are not all the side effects of Kyzatrex®. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088.

Stop using your medication and seek urgent medical care if serious side effects occur.

Overdose

In case of overdose, seek medical attention immediately or contact Poison Control at 1-800-222-1222.

Missed Dose

Take the missed dose as soon as you remember, as long as you can take it with food. If it is almost time for your next scheduled dose, skip the missed dose and take your next dose as usual. Do not take extra capsules to make up for a missed dose. If you miss doses often or aren’t sure what to do, reach out to your Care Team.

Storage

  • Store at room temperature between 68°F and 77°F (20°C to 25°C), in a dry place away from heat and moisture

  • Keep out of the reach of children

Medication Disposal

Because testosterone is a controlled substance, the best way to dispose of unused or expired Kyzatrex® is to drop it off at a DEA drug take-back site. You can use the DEA Diversion Control Division lookup to find your nearest site. Do not flush unused medication or pour it down a drain.

If no take-back option is available, you can dispose of the capsules in your household trash: mix them (do not crush) with an unappealing substance such as dirt, cat litter, or used coffee grounds; seal the mixture in a plastic bag; throw it in the trash; and remove personal information from the bottle before recycling or discarding it. For more information, visit FDA – Disposal of Unused Medicines.

Telemedicine Disclosure: This prescription was issued via telemedicine. If you experience any concerning symptoms, contact your prescribing clinician or seek emergency care.

Disclaimer: This summary does not include all information about Kyzatrex®. For more details, speak with your healthcare provider or pharmacist. This information is intended to support, not replace, discussions with your healthcare provider.