Cases of benign and malignant liver tumours have been reported in users of hormonal substances such as androgen compounds. If severe upper abdominal complaints, liver enlargement or signs of intra-abdominal haemorrhage occur in men using Nebido, a liver tumour should be included in the differential-diagnostic considerations. In patients suffering from severe cardiac, hepatic or renal insufficiency or ischemic heart disease, treatment with testosterone may cause severe complications characterized by oedema with or without congestive cardiac failure.
Because testosterone replacement therapy impairs production of sperm, it should be used with caution in men with fertility concerns. Other conditions can potentially be made worse by testosterone therapy, including sleep apnoea, severe benign prostatic hypertrophy, severe congestive heart failure, or high red blood cell counts (erythrocytosis).
Regular checks on your prostate health during testosterone treatment are recommended as part of routine health care. The amount of red blood cells in the blood should also be checked periodically.
Abuse or overuse of testosterone treatment can be dangerous. For example, using higher than replacement doses to increase muscle bulk can lead to impotence, liver disease, heart attack, and stroke.
Before starting any new treatment, be sure to tell your doctor about any other medication you are taking.