Testosterone is a naturally occurring sex hormone produced in a man's testicles. Small amounts of testosterone are also produced in a woman's ovaries and adrenal system.

Testosterone injection is used in men and boys to treat conditions caused by a lack of this hormone, such as delayed puberty, impotence, or other hormonal imbalances. Testosterone injection is not for use in treating low testosterone without certain medical conditions or due to getting older.

Testosterone enanthate is used in women to treat breast cancer that has spread to other parts of the body (metastatic) and cannot be treated with surgery.

Testosterone will not enhance athletic performance and should not be used for that purpose.

Testosterone injection may also be used for purposes not listed in this medication guide.

You should not be treated with testosterone if you have prostate cancer, male breast cancer, a serious heart condition, severe liver or kidney disease, or an allergy to castor oil or sesame oil. testosterone injection is not for use in treating low testosterone without certain medical conditions or due to getting older. Testosterone should not be used to enhance athletic performance.

Testosterone injection is not for use in women who are pregnant.

Testosterone can increase your risk of heart attack, stroke, or death. You may need to stop using testosterone or start taking blood pressure medication.

Misuse of testosterone can cause dangerous or irreversible effects. Do not share this medicine with another person.

Testosterone is injected under the skin or into a muscle, usually given every 2 to 4 weeks. Testosterone injections should be given only by a healthcare professional.

The length of treatment with testosterone injection will depend on the condition being treated.

Testosterone can raise your blood pressure, which could increase your risk of heart attack, stroke, or death. Your blood pressure will need to be checked often. You may need to stop using testosterone or start taking blood pressure medication.

You will need frequent blood tests.

Testosterone can affect bone growth in boys who are treated for delayed puberty. Bone development may need to be checked with x-rays every 6 months during treatment.

testosterone injection can affect the results of certain medical tests. Tell any doctor who treats you that you are using testosterone.

Misuse of testosterone can cause dangerous or irreversible effects, such as enlarged breasts, small testicles, infertility, high blood pressure, heart attack, stroke, liver disease, bone growth problems, addiction, and mental effects such as aggression and violence. Stealing, selling, or giving away this medicine is against the law.

If you have used too much testosterone, stopping the medicine may caused unpleasant withdrawal symptoms, such as depression, tiredness, irritability, loss of appetite, sleep problems, or decreased libido.

You should not be treated with this medicine if you are allergic to testosterone, or if you have:

• male breast cancer;

• prostate cancer;

• serious heart problems;

• severe liver disease;

• severe kidney disease; or

• an allergy to castor oil or sesame oil.

Testosterone injection is not for use in women who are pregnant. This medicine can harm an unborn baby.

Tell your doctor if you have ever had:

• high blood pressure;

• heart problems, coronary artery disease (clogged arteries);

• a heart attack or stroke;

• sleep apnea;

• an enlarged prostate and urination problems;

• high cholesterol or triglycerides;

• cancer;

• depression, anxiety, a mood disorder, suicidal thoughts or actions;

• diabetes;

• high red blood cell (RBC) counts; or

• liver or kidney disease.

Using testosterone may increase your risk of developing prostate cancer, liver problems, or heart problems (including heart attack, stroke, or death). Ask your doctor about these risks.

Women using testosterone should not breastfeed.

Testosterone should not be given to a child younger than 12 years old. Some types of this medicine are not approved for use by anyone younger than 18 years old.

Call your doctor for instructions if you miss an appointment for your testosterone injection.

Since testosterone injection is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your caregivers right away if you have a tight feeling in your throat, a sudden urge to cough, or if you feel light-headed or short of breath during or shortly after receiving the injection.

You will be watched closely for at least 30 minutes to make sure you do not have a reaction to the injection.

Testosterone injection may cause serious side effects. Call your doctor at once if you have:

• chest pain or pressure, pain spreading to your jaw or shoulder;

• shortness of breath, breathing problems at night (sleep apnea);

• swelling in your ankles or feet, rapid weight gain;

• a seizure;

• unusual changes in mood or behavior;

• increased or ongoing erection of the penis, ejaculation problems, decreased amounts of semen, decrease in testicle size;

• painful or difficult urination, increased urination at night, loss of bladder control;

• high levels of calcium in the blood--stomach pain, constipation, increased thirst or urination, muscle pain or weakness, joint pain, confusion, and feeling tired or restless; or

• high potassium level--nausea, weakness, tingly feeling, chest pain, irregular heartbeats, loss of movement;

• liver problems--right-sided upper stomach pain, vomiting, loss of appetite, dark urine, jaundice (yellowing of the skin or eyes).

• signs of a blood clot deep in the body--swelling, warmth, or redness in an arm or leg;

• signs of a blood clot in the lung--chest pain, sudden cough, wheezing, rapid breathing, coughing up blood; or

• signs of a stroke--sudden numbness or weakness (especially on one side of the body), severe headache, slurred speech, balance problems.

Women receiving testosterone may develop male characteristics, which could be irreversible if treatment is continued. Call your doctor at once if you notice any of these signs of excess testosterone:

• acne;

• changes in your menstrual periods (including missed periods);

• male-pattern hair growth (such as on the chin or chest);

• hoarse or deepened voice; or

• enlarged clitoris.

Your testosterone injections may be delayed or permanently discontinued if you have certain side effects.

Common side effects (in men or women) may include:

• breast swelling;

• acne, increased facial or body hair growth, male-pattern baldness;

• increased or decreased interest in sex;

• headache, anxiety, depressed mood;

• increased blood pressure;

• numbness or tingly feeling;

• abnormal liver function tests;

• high red blood cell counts (hematocrit or hemoglobin);

• increased PSA (prostate-specific antigen); or

• pain, bruising, bleeding, redness, or a hard lump where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your other medicines, especially:

• insulin or oral diabetes medicine;

• medicine to treat pain, cough, or cold symptoms;

• a blood thinner--warfarin, Coumadin, Jantoven; or

• steroid medicine--prednisone, dexamethasone, and others.

This list is not complete. Other drugs may affect testosterone, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.