Testosterone belongs to the class of medications called androgens (male hormones). This medication is used to replace testosterone in men who have conditions caused by low testosterone levels.

This medication works by replacing the testosterone that the body is missing. Testosterone cypionate should only be used if testosterone deficiency has been confirmed by symptoms and blood tests.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

The usual adult dose of testosterone cypionate in men is 200 mg every two weeks, to a maximum of 400 mg per month. It is given as an injection into the gluteal muscle (buttocks) by a doctor.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important this medication be given exactly as recommended by your doctor. If you miss an appointment to receive testosterone cypionate, contact your doctor as soon as possible to reschedule your appointment.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Each mL of injectable solution contains 100 mg of testosterone cypionate. Nonmedicinal ingredients: benzyl alcohol, benzyl benzoate, and cottonseed oil.

Do not use this medication if you:

• are allergic to testosterone or any ingredients of the medication
• are female (especially if you are pregnant or breast-feeding)
• have, or are suspected to have, prostate or breast cancer

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• acne
• aggressive behaviour
• dizziness
• enlarged prostate
• hair loss, thinning hair, or baldness
• headache
• mood changes
• sleep disturbances caused by breathing problems (sleep apnea)
• skin irritation or redness at the injection site
• weight gain

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• blurred vision or vision changes
• breast soreness or enlargement
• fast or irregular heartbeat
• high blood pressure
• problems with urination (change in frequency or colour, dribbling, pain or straining when urinating, weak urine stream, small urine amounts)
• prolonged (more than 4 hours) or painful erections, or erections that happen too often
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• signs of a blood clot in the arm or leg (tenderness, pain, swelling, warmth, or redness in the arm or leg) or lungs (difficulty breathing, sharp chest pain that is worst when breathing in, coughing, coughing up blood, sweating, or passing out)
• swelling of ankles and legs (for people with heart, liver, or kidney problems)
• symptoms of liver problems, such as:
• abdominal pain
• dark urine
• loss of appetite
• nausea or vomiting
• pale stools
• yellow eyes or skin

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a heart attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)
• signs of stroke (e.g., sudden or severe headache; sudden loss of coordination; vision changes; sudden slurring of speech; or unexplained weakness, numbness, or pain in arm or leg)
• symptoms of a serious allergic reaction, such as:
• difficulty breathing
• hives
• rash
• swollen face or throat

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Blood tests: Your doctor may recommend that you have regular blood tests while using this medication to check whether the medication is working and whether you are having certain side effects. Also, the use of testosterone may interfere with a number of laboratory tests. Tell all health professionals administering these tests that you are using this medication.

Cancer: Men who use androsterones such as testosterone cypionate may be at an increased risk for developing prostate or breast cancer. Discuss any concerns you may have about this with your doctor.

Diabetes: Testosterone cypionate may cause a loss of blood glucose control and glucose tolerance may change. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication. If you have diabetes or are at risk for developing diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Heart disease: Testosterone cypionate can cause increased blood pressure and may cause fluid to build up in the body. Both conditions can increase the risk of certain types of heart disease.

In addition, androgens have been linked to increased risk of heart disease, including congestive heart failure, heart attack and stroke. If you have heart disease or risk factors for developing heart disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Kidney function: People with kidney disease or reduced kidney function may be more likely to experience fluid build-up (edema). If you have kidney problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

Report any swelling in the feet and lower legs to your doctor immediately.

Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

This medication may also reduce liver function and can cause liver failure. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Sleep disorders: Treatment with testosterone may cause sleep apnea (interruption of breathing during sleep) , especially for individuals with risk factors such as being overweight or having a chronic lung disease.

Sperm counts: This medication may reduce sperm counts if high doses are used, or if it is used for a prolonged period.

Pregnancy: This medication is not intended to be used by women. Because testosterone can harm the developing baby, it is recommended that pregnant women avoid exposure to this medication.

Breast-feeding: This medication is not intended to be used by women and should not be used while breast feeding.

Children: Testosterone cypionate has been given to male adolescents who experience delayed puberty because of inadequate levels of testosterone in the body. When a child has not finished growing, androgens such as testosterone can cause the bones to mature without growing. This causes the adolescent to stop growing before full height can be reached. Your child's doctor will assess the bone development on a regular basis.

Seniors: Seniors may have an increased risk for prostate enlargement and should be evaluated for prostate cancer before starting testosterone replacement therapy.

There may be an interaction between testosterone cypionate and any of the following:

• abiraterone
• busulfan
• corticosteroids (e.g., hydrocortisone, prednisone, methylprednisolone)
• cyclosporine
• darbepoetin alfa
• dehydroepiandrosterone
• diabetes medications (e.g.,  acarbose, canagliflozin, glyburide, insulin, linagliptin, lixisenatide, metformin, rosiglitazone)
• disopyramide
• esketamine
• hydroxychloroquine
• octreotide
• pasireotide
• protein kinase inhibitors (e.g., dasatinib, ibrutinib, lenvatinib, sunitinib)
• quinine
• sirolimus
• somatostatin
• sulfamethoxazole
• tacrolimus
• tramadol
• warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.