Hypogonadism

A low testosterone result is a clue, not a diagnosis. Male hypogonadism is diagnosed when androgen-deficiency symptoms or signs occur with repeatedly and unequivocally low testosterone, then the level of the hypothalamic–pituitary–gonadal axis is localized. High LH and FSH point toward testicular failure; low or inappropriately normal gonadotropins point toward hypothalamic or pituitary disease. That distinction changes the next investigation, the likelihood of reversing the cause, and the fertility discussion. The treatment decision is equally specific. Weight loss or medication review may correct functional secondary hypogonadism, whereas organic testicular or central disease may require hormone replacement. Exogenous testosterone improves androgen deficiency but suppresses LH, FSH, and sperm production. In Canada, testosterone is a controlled drug; NPs may prescribe it under the federal New Classes of Practitioners Regulations, within applicable provincial or territorial authority and standards.