Blood counts. Check haematocrit before starting, at 3 to 6 months, at 12 months and then yearly, and pause the therapy if it rises above 54% (Bhasin et al., 2018, PMID 29562364).

Prostate marker. If he chooses prostate screening, check PSA before starting and at 3 to 12 months, then on the usual screening schedule. Refer to urology for a rise of more than 1.4 ng/mL within a year or a confirmed level above 4.0 ng/mL (Bhasin et al., 2018).

Safety. In men aged 45 to 80 at high cardiovascular risk, the therapy was non-inferior to placebo for major cardiovascular events. Atrial fibrillation, acute kidney injury and pulmonary embolism were more frequent (Lincoff et al., 2023, PMID 37326322).

For this patient. At 58 he is in the guideline's age range for PSA checks. Take a baseline haematocrit and PSA if none exists, then follow the schedule above.

Limit. The intervals rest on expert consensus, not on trials comparing schedules.