Testosterone Replacement Therapy: What Men Need to Know

Testosterone is the primary male sex hormone — responsible for muscle mass, bone density, sex drive, energy, mood, and much more. Yet millions of men are walking around with levels well below the normal range, often attributing their symptoms to "just getting older."

Low testosterone (also called hypogonadism or "Low T") is a real medical condition, and testosterone replacement therapy (TRT) is a well-established treatment that can significantly improve quality of life for the right candidates.

At Manatee Primary Care, we evaluate and manage testosterone levels as part of comprehensive men's health care. Here is what you need to know.

Testosterone is produced primarily in the testes, with a small amount from the adrenal glands. It plays a central role in:

• Muscle mass and strength
• Bone density
• Red blood cell production
• Fat distribution
• Sperm production and fertility
• Sex drive (libido)
• Mood, motivation, and cognitive function
• Energy levels

Testosterone peaks in the late teens and early twenties, then declines gradually — roughly 1–2% per year after age 30. This is normal. However, some men experience a more significant drop that crosses into clinically low territory, causing symptoms that affect daily life.

Low T can be subtle and easy to dismiss. Common symptoms include:

• Persistent fatigue — feeling tired even after adequate sleep
• Reduced sex drive — decreased interest in sexual activity
• Erectile dysfunction — difficulty achieving or maintaining erections
• Loss of muscle mass — despite regular exercise
• Increased body fat — particularly around the abdomen
• Mood changes — irritability, depression, difficulty concentrating, or "brain fog"
• Decreased bone density — increasing fracture risk
• Reduced body and facial hair
• Hot flashes or night sweats (less common)
• Smaller testicle size

Many of these symptoms overlap with other conditions — thyroid disease, sleep apnea, depression, diabetes — which is why proper testing is essential before starting any treatment.

Diagnosis requires a blood test measuring total testosterone levels, typically drawn in the morning when levels are highest. Normal total testosterone in adult men ranges from approximately 300 to 1,000 ng/dL. Levels consistently below 300 ng/dL, combined with symptoms, generally meet the criteria for treatment.

Your doctor will also check:

• Free testosterone — the biologically active portion not bound to proteins
• LH and FSH — hormones from the pituitary gland that signal the testes to produce testosterone
• Prolactin — elevated levels can suppress testosterone
• Complete blood count (CBC) — TRT increases red blood cell production; a baseline is important
• PSA (prostate-specific antigen) — to screen for prostate issues before starting therapy
• Hematocrit — to monitor for polycythemia (thickening of the blood)

Two separate low readings on different days are typically required before a diagnosis is confirmed.

TRT is available in several forms. Your doctor will recommend the best option based on your lifestyle, preferences, and medical history.

Applied daily to the shoulders, upper arms, or inner thighs. Convenient and easy to use, but require care to avoid skin-to-skin transfer to partners or children.

Testosterone cypionate or enanthate injected into the muscle — typically every one to two weeks, or more frequently in smaller doses. Injections produce the most predictable and cost-effective results and are the most commonly used form in primary care.

Applied to the skin daily. Provide steady hormone levels but can cause skin irritation in some patients.

Small pellets implanted under the skin of the buttock every three to six months. Provide consistent levels without daily administration.

Newer oral testosterone formulations are available and may be appropriate for select patients.

When prescribed appropriately, TRT can produce meaningful improvements in:

• Energy and vitality
• Libido and sexual function
• Mood and sense of well-being
• Muscle mass and body composition
• Bone density
• Cognitive clarity

Most men notice improvements within four to six weeks, with full benefits developing over three to six months.

TRT is not appropriate for everyone, and it carries potential risks that must be monitored:

Fertility: TRT suppresses the body's natural testosterone production and significantly reduces sperm count. Men who wish to father children should discuss alternatives (such as clomiphene citrate or hCG) before starting TRT.

Polycythemia: TRT stimulates red blood cell production, which can thicken the blood and increase clotting risk. Regular hematocrit monitoring is essential.

Prostate health: TRT is contraindicated in men with known or suspected prostate cancer. PSA should be monitored regularly during treatment.

Cardiovascular effects: The relationship between TRT and cardiovascular risk has been studied extensively. Recent large trials suggest TRT does not increase — and may modestly reduce — cardiovascular events in men with confirmed hypogonadism. Your doctor will assess your individual risk profile.

Sleep apnea: TRT can worsen sleep apnea in susceptible individuals. If you snore heavily or have daytime sleepiness, a sleep study may be recommended before starting treatment.

Testicular atrophy: Because TRT suppresses the body's own production, the testes may decrease slightly in size over time.

TRT is generally not recommended for men with:

• Prostate or breast cancer
• Untreated severe sleep apnea
• Uncontrolled heart failure
• A desire to preserve fertility in the near term
• Hematocrit above 54%
• Normal testosterone levels with non-hormonal causes of symptoms

TRT is not a "set it and forget it" therapy. Regular follow-up is essential:

• At 3 months: Testosterone levels, hematocrit, PSA
• At 6 months: Repeat labs, symptom review, dose adjustment if needed
• Annually: Ongoing labs, bone density if indicated, cardiovascular risk assessment

If you have been experiencing persistent fatigue, low libido, mood changes, or unexplained weight gain, it is worth having your testosterone levels checked. Many men are surprised to find that a treatable hormonal imbalance has been affecting their quality of life for years.

At Manatee Primary Care, we take a thorough, evidence-based approach to men's hormonal health — starting with proper diagnosis, discussing all treatment options, and monitoring your response over time.

Call us at (941) 867-9362 or request an appointment to schedule a men's health evaluation today.