What Qualifies as Low Testosterone for Men

Low testosterone, often referred to as Low T, occurs when the body does not produce enough of the hormone needed to support optimal health and function. While testosterone levels can vary between individuals, the American Urological Association (AUA) considers a total testosterone level below 300 ng/dL as a reasonable threshold for diagnosing low testosterone.

However, laboratory results alone are not enough to confirm a diagnosis. A qualified healthcare provider will also assess clinical symptoms, overall health, and potential contributing factors. Common signs of testosterone deficiency include low energy, reduced libido, mood changes, and loss of muscle mass.

Because hormone levels fluctuate throughout the day, it’s important to undergo accurate testing and professional evaluation before considering treatment. Different healthcare providers may use slightly varied diagnostic criteria, so working with a trusted medical professional who specializes in hormone therapy ensures that your dosage plan is personalized, evidence-based, and safe.

Testosterone Levels After Injection

Here’s what happens after your first testosterone injection: your body absorbs the hormone, causing a steady increase in your blood testosterone levels. According to the American Urological Association, an ideal testosterone level is typically between 450 and 600 ng/dL, though this can vary depending on individual health factors and goals.

After an injection, testosterone levels typically peak around 24 to 48 hours post-injection. From there, testosterone levels begin to drop at a rate of approximately 1-2% per day. This gradual decline continues over the next several days, with levels generally returning to baseline just before your next scheduled dose.