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Should Cortisol Blood Test be Done Before 9am Even if I Work Night Shifts?

Hey all, kind of a specific question:

Went to have some pre TRT comprehensive bloods done, and was told the cortisol test needs to be drawn by 9am. Just wanted to clarify- is relative to the average circadian rhythm? Because I work nights, and generally sleep from 2-3am until 10-11am.

If I wake up earlier than normal, will this affect my cortisol levels?


Not wanting to hijack your thread Sean, but i’d like an answer to this question in relation to blood tests in general. I work some pretty unsociable hours (this week for instance M 0300, T 0700, W-F 1900, S 1600), do timings for blood tests make a huge difference?

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@systemlord @KSman Hey guys, going to get these bloods done in the next couple days. My doc is clueless so I’m hoping for a little insight.

Thanks, I really appreciate it guys.

Should be AM Cortisol, done at 8AM or 1 hour after waking up.

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