From the Guidelines
Hypogonadism, or testosterone deficiency, is characterized by symptoms such as reduced energy, fatigue, depression, reduced motivation, poor concentration, impaired memory, irritability, infertility, reduced sex drive, and changes in erectile function, which must be accompanied by a total testosterone level below 300 ng/dL for diagnosis. When evaluating patients for hypogonadism, clinicians should consider the presence of select symptoms and/or signs, including patient-reported symptoms 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. Some key points to consider in the diagnosis of hypogonadism include:
- The diagnosis of low testosterone should be made only after two total testosterone measurements are taken on separate occasions with both conducted in an early morning fashion 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.
- A targeted physical exam should be conducted to examine patients for signs associated with low testosterone, including evaluation of general body habitus, virilization status, body mass index or waist circumference, gynecomastia, testicular evaluation, varicocele presence, and prostate size and morphology 1. It is essential to note that 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. Instead, clinicians should rely on a combination of patient-reported symptoms, physical examination, and laboratory testosterone measurements to diagnose and manage hypogonadism.
From the FDA Drug Label
Male hypogonadism, a clinical syndrome resulting from insufficient secretion of testosterone, has two main etiologies. Primary hypogonadism is caused by defects of the gonads, such as Klinefelter's syndrome or Leydig cell aplasia, whereas secondary hypogonadism is the failure of the hypothalamus (or pituitary) to produce sufficient gonadotropins (FSH, LH).
The symptoms of hypogonadism (testosterone deficiency) are not explicitly listed in the provided drug label. However, it can be inferred that the condition is characterized by insufficient secretion of testosterone, which can lead to a range of symptoms.
- Primary hypogonadism is caused by defects of the gonads.
- Secondary hypogonadism is caused by the failure of the hypothalamus or pituitary to produce sufficient gonadotropins. Since the label does not provide a direct list of symptoms, a conservative clinical decision would be to consult other medical resources for a comprehensive understanding of the symptoms associated with hypogonadism 2.
From the Research
Symptoms of Hypogonadism
The symptoms of hypogonadism, also known as testosterone deficiency, include:
- Decreased libido 3, 4, 5
- Erectile dysfunction 3, 4
- Depressed mood 4, 5
- Fatigue 5
- Muscle weakness 5
- Loss of muscle and bone mass 4, 5
- Anaemia 4
- Osteoporosis 5
- Increased adiposity 5
- Mood changes 5
- Reduced muscle mass 5
Diagnosis and Treatment
Diagnosis of hypogonadism is based on clinical manifestations, including decreased serum androgen concentrations or activity, regardless of whether there is an identified underlying etiology 3. Treatment options include testosterone replacement therapy (TRT), which can improve symptoms and signs of testosterone deficiency 6, 3, 4, 5, 7.
Testosterone Replacement Therapy
TRT has been used for over 70 years and numerous preparations and formulations have been developed to improve pharmacokinetics and patient compliance 4. The routes of delivery approved for use in the Western world include buccal, nasal, subdermal, transdermal, and intramuscular (IM) 4. The goal of TRT is to achieve serum testosterone levels in the mid-normal range during treatment 7.