At what testosterone level should treatment be initiated?

From the Guidelines

Testosterone replacement therapy should be considered when a man's total testosterone level falls below 300 ng/dL, especially if accompanied by symptoms of low testosterone. Before starting treatment, it's essential to have at least two separate morning blood tests confirming low levels, as testosterone naturally fluctuates throughout the day and is highest in the morning 1. The diagnosis of testosterone deficiency requires both a low testosterone measurement as well as the presence of select symptoms and/or signs, such as reduced energy, reduced endurance, diminished work and/or physical performance, fatigue, visual field changes, anosmia, depression, reduced motivation, poor concentration, impaired memory, irritability, infertility, reduced sex drive, and changes in erectile function 1.

Key Considerations

• The therapy usually begins with a moderate dose, such as 50-100 mg of testosterone cypionate or enanthate injected weekly, 5-10 g of testosterone gel applied daily, or a testosterone patch 1.
• Treatment should be individualized based on age, symptoms, and medical history.
• Regular monitoring is crucial, with follow-up testosterone level checks after 2-3 months of therapy, aiming for mid-normal range levels (around 500-600 ng/dL) 1.
• Clinicians should consider measuring total testosterone in patients with a history of unexplained anemia, bone density loss, diabetes, exposure to chemotherapy, exposure to testicular radiation, HIV/AIDS, chronic narcotic use, male infertility, pituitary dysfunction, and chronic corticosteroid use even in the absence of symptoms or signs associated with testosterone deficiency 1.

Important Recommendations

• The use of validated questionnaires is not currently recommended to either define which patients are candidates for testosterone therapy or monitor symptom response in patients on testosterone therapy 1.
• Clinicians should discuss whether to initiate testosterone treatment in men with age-related low testosterone with sexual dysfunction who want to improve sexual function, and reevaluate symptoms within 12 months and periodically thereafter 1.
• Clinicians should discontinue testosterone treatment in men with age-related low testosterone with sexual dysfunction in whom there is no improvement in sexual function 1.

From the FDA Drug Label

Prior to initiating testosterone gel 1. 62%, confirm the diagnosis of hypogonadism by ensuring that serum testosterone has been measured in the morning on at least two separate days and that these concentrations are below the normal range The starting testosterone level to try testosterone gel 1.62% is not explicitly stated, but hypogonadism is indicated by serum testosterone concentrations below the normal range.

• The normal range is not defined in the provided drug label. 2

From the Research

Testosterone Levels for Starting Therapy

The decision to start testosterone replacement therapy (TRT) depends on various factors, including the patient's age, symptoms, and testosterone levels. According to the study 3, a serum total testosterone level of less than 300 to 350 ng/dL on two separate morning blood samples is considered a low level. However, another study 4 suggests that this cutoff may not be suitable for young men, and age-specific cutoffs should be used instead.

Age-Specific Testosterone Levels

The study 4 analyzed data from the National Health and Nutrition Examination Surveys and found that age-specific middle tertile levels for men 20 to 44 years old were:

• 409-558 ng/dL (20-24 years old)
• 413-575 ng/dL (25-29 years old)
• 359-498 ng/dL (30-34 years old)
• 352-478 ng/dL (35-39 years old)
• 350-473 ng/dL (40-44 years old) The study suggests that these age-specific cutoffs should be used to diagnose testosterone deficiency in young men.

Factors to Consider Before Starting TRT

Before starting TRT, several factors should be considered, including:

• The patient's symptoms and medical history
• The potential benefits and risks of TRT
• The choice of testosterone formulation, which depends on factors such as cost and patient preference 3
• The need for close monitoring of patients receiving TRT 3, 5

Testosterone Replacement Therapy Formulations

Various testosterone formulations are available, including:

• Topical gels
• Intramuscular injections
• Subcutaneous injections
• Buccal and nasal preparations The choice of formulation depends on individual patient needs and preferences 3, 5, 6.