Overview
Testosterone is a sex hormone found in all people, but it is present at much higher levels in males. It helps guide puberty, sexual function, sperm production, muscle mass, bone strength, and red blood cell production. Testosterone levels naturally vary by age, time of day, and overall health. A single symptom does not prove that testosterone is low or high.
Key Symptoms
Possible signs of low testosterone may include lower sex drive, erection problems, reduced morning erections, tiredness, depressed mood, trouble concentrating, loss of muscle mass, and lower bone strength over time. In adolescents, delayed puberty may be a sign of low testosterone production. High testosterone is less commonly a natural medical problem and may be linked to acne, mood changes, or fertility problems, especially when caused by non-prescribed hormone or steroid use.
Causes and Risk Factors
Testosterone can be low because of problems in the testes or in the brain areas that control hormone production, such as the pituitary gland. Risk factors and related causes include aging, obesity, long-term illness, diabetes, sleep problems such as obstructive sleep apnea, injury to the testes, certain infections, chemotherapy, radiation, heavy alcohol use, and some medicines including opioids or long-term steroids. Anabolic steroid use can also disrupt the body's own testosterone production.
Who Is Affected
People of all ages can have testosterone-related conditions, but the reasons differ by life stage. Newborns and children may be affected by congenital or developmental conditions. Teenagers may show delayed or disrupted puberty. Adult men may notice sexual, mood, energy, or fertility-related symptoms, and older men may have age-related declines that overlap with other health conditions.
Diagnosis and Tests
Diagnosis starts with symptoms, a health history, and a physical exam. Testosterone is usually checked with a morning blood test, and healthcare professionals may repeat the test because levels can change from day to day. Other tests may look at pituitary hormones, thyroid function, blood count, iron levels, blood sugar, or causes of fertility problems, depending on the situation.
Treatment Categories
Treatment depends on the cause, the person's age, symptoms, fertility plans, and whether testing confirms an abnormal level. Care may include treating an underlying condition, adjusting medicines when appropriate, managing sleep apnea, addressing body weight, or specialist care for pituitary or testicular disorders. Testosterone therapy may be considered for some people after medical evaluation, but it is not appropriate for everyone and can affect fertility and require monitoring.
Diet and Lifestyle
General health habits can support hormone health, even though they may not fix every testosterone problem. Regular physical activity, enough sleep, limiting alcohol, avoiding non-prescribed anabolic steroids, and managing long-term conditions such as obesity or diabetes may help. A varied diet that supports overall nutrition, bone health, and weight management is also important.
When to Seek Medical Care
Make a medical appointment if you have ongoing low sex drive, erection problems, unexplained tiredness, depressed mood, loss of body hair, infertility concerns, delayed puberty, breast enlargement, or reduced muscle strength. Seek care if symptoms start after starting a new medicine or after injury, chemotherapy, or radiation. Children and teenagers with delayed puberty should be assessed by a qualified healthcare professional.
When It May Be an Emergency
Urgent evaluation is needed if symptoms happen with severe headache, vision changes, fainting, sudden weakness, confusion, chest pain, or serious injury to the groin or testes. Emergency care is also important for sudden, severe testicular pain or swelling because some causes need rapid treatment. These symptoms may point to conditions that are more urgent than a hormone problem alone.
Questions to Ask a Healthcare Professional
You may want to ask what might be causing your symptoms, whether testing should be repeated, and whether another condition could explain the problem. Ask how fertility could be affected, what monitoring is needed, and whether current medicines, sleep issues, weight, or alcohol use may be playing a role. If treatment is discussed, ask about expected benefits, limits, and possible risks.