What Is Testosterone?
Testosterone is a sex hormone that’s primarily responsible for helping develop male characteristics like facial hair and a deeper voice. It’s also responsible for the development of the reproductive system and its function. Most testosterone is made in the testicles.
Testosterone production increases significantly in puberty. This helps young men to begin producing sperm, as well as to grow body hair and increase muscle mass. Testosterone then slowly declines after about age 30. When testosterone levels are too low, some men have noticeable symptoms.
Some men are born with conditions that cause low testosterone. For millions of other men, it’s a result of aging.
Note: women also produce testosterone, but in much smaller amounts. It plays a part in the development of female reproductive tissues, bone mass, and some behaviors. Women produce testosterone in their ovaries.
What Is Testosterone Deficiency Syndrome?
When the testicles don’t make enough testosterone, it’s called testosterone deficiency syndrome. Testosterone deficiency syndrome is also called low testosterone and hypogonadism. You may hear it more casually referred to as Low-T.
Low testosterone can affect multiple body systems, affecting hair growth, mental health, and bone density, for example.
An estimated 2% of men under the age of 50 have low testosterone, and the numbers rise with age to about 8% of men over 50.
Signs and Symptoms of Low Testosterone
Some men with low testosterone don’t have any symptoms. When symptoms are present, they can vary from person to person but may include:
- Decreased muscle mass
- Decreased sex drive
- Depression, moodiness
- Difficulty concentrating
- Erectile dysfunction
- Fatigue
- Growth of breast tissue (gynecomastia)
- Hot flashes
- Increased body fat
- Loss of body and facial hair
- Low sperm count, fertility issues
- Obesity
- Poor memory
- Shrinking testicles
- Sleep problems
- Thinning bones (osteoporosis)
Having one or more symptoms doesn’t always mean you have low testosterone. Many of these symptoms are also associated with other conditions. If you have some of these symptoms or if you have new symptoms, you should see your doctor for a diagnosis.
Risk Factors
Low testosterone can affect any man with testicles at any age, but certain factors can increase the risk of developing it, including:
- Age – testosterone levels decrease with age
- Chronic medical conditions like kidney disease or cirrhosis
- HIV/AIDS
- Metabolic syndrome – belly fat, high blood pressure, blood sugar, unhealthy cholesterol
- levels
- Obesity
- Obstructive sleep apnea (OSA)
- Some medications, like narcotic pain medications and antidepressants
- Type 2 diabetes that is poorly managed
Causes Of Low Testosterone
Low testosterone can develop from conditions present at birth, like:
- Ambiguous genitalia (genitals aren’t clearly male or female)
- Klinefelter syndrome (when a male is born with an extra X chromosome)
- Noonan syndrome (a genetic mutation that can cause genital problems)
It can also be a result of conditions that develop later in life, like:
- Autoimmune disease
- Cancer requiring the removal of testicles
- Chemotherapy or radiation treatment
- Damaged testicles
- Hormone deficiency due to pituitary gland disease
- Infection
Diagnosing Low Testosterone
To diagnose low testosterone, your doctor will ask questions about your health history, give you a physical examination, and assess you for possible signs and symptoms of low testosterone. If low testosterone is suspected, a blood test measuring the level of testosterone in your blood can verify the diagnosis.
Health history
Your doctor may ask questions about your growth, medical history, and family history to help rule out other causes of your symptoms. He may ask about:
- Any use of anabolic steroids or glucocorticoid steroids for inflammation
- Family history of diseases that may be linked to low testosterone
- Headache or visual problems
- History of head trauma, brain surgery, or radiation treatment
- History of infection or injury to your testicles
- History of stroke, heart attack, or unexplained anemia
- Use of opioids
- Your development at puberty
Physical examination
A physical examination may include:
- Blood pressure
- BMI measurement
- Condition and size of the prostate
- Enlarged breast tissue (gynecomastia)
- Hair amount, location, and pattern
- Testicle size
Lab tests and imaging
You may have blood tests to check your levels of:
- Blood sugar
- Bone density test
- Cholesterol, triglycerides
- Estradiol hormone if you have breast tissue symptoms
- Follicle-stimulating hormone (FSH) if you plan to have children
- Hemoglobin (Hgb)
- Hemoglobin A1C for diabetes
- Karyotype (chromosome tests)
- Luteinizing hormone, which may indicate a problem with the pituitary gland
- Magnetic resonance imaging (MRI) to look at the pituitary gland
- Prolactin level, which may indicate problems with the pituitary gland
- Total testosterone
Treatment
If your symptoms and tests verify a diagnosis of low testosterone, you and your doctor may decide that testosterone therapy (TT) is right for you. Losing weight and increasing physical activity can often raise testosterone levels as well.
You should notice results within 3-6 months. During treatment, your doctor may need to repeat blood tests to monitor your levels of testosterone, hemoglobin, and hematocrit.
Treatment methods
There are five common ways to take testosterone treatment. Each is equally as good as the others. The method you choose may be based on your preferences or may be determined by your insurance company.
- Injections can be short- or long-lasting and are typically given weekly, every two weeks, or monthly.
- Intranasal testosterone is in a gel form that you pump into your nostril, typically three times daily.
- Oral/buccal (by mouth) testosterone is a small patch that you put on your gums. The medicine is then released over 12 hours.
- Pellets are inserted under your skin, typically in the buttocks or hip. The pellets dissolve over time, typically about 3-6 months.
- Transdermal testosterone is placed on your skin and typically last about four days. Transdermal varieties can be a gel, cream, liquid, or patch.
Side Effects
Some men report side effects from testosterone therapy, which may include:
- Allergic reactions to long-acting injections
- Back pain
- From pellets – swelling, pain, bruising, blood clot at the site
- Increased levels of blood hematocrit and hemoglobin (erythrocytosis)
- Interruption of normal sperm production
- Reactions at the injection site of short-acting injections
- Skin redness, itching, or rash from gels, liquids, or patches.
When using topical testosterone, it’s important to remember that creams, gels, and liquids can transfer to other people who come into contact with the application site. Women and children could suffer harmful effects from contact with testosterone treatment. To keep your loved ones safe, always wash your hands after applying testosterone and cover the application site.