Glucocorticoid replacement

Hydrocortisone (replacement)

Also known as: Cortef, Plenadren

Best time

Largest dose on waking, smaller early afternoon

06:00–08:00· Main dose on waking
12:00–14:30· Smaller dose

For adrenal insufficiency, doses mimic the natural cortisol curve: high in the morning, low by evening.

Strong evidence

Consistent clinical trials or official prescribing guidance support this timing.

Why this time works

People with adrenal insufficiency lack the cortisol morning peak. Splitting doses — the largest on waking, smaller ones by early afternoon — recreates the natural curve and avoids high evening levels that disrupt sleep and metabolism.

Body rhythm involved

Cortisol rises before waking and falls to its lowest at midnight.

Other hormones & diabetes medicines

Levothyroxine

Synthroid, Euthyrox

On waking, empty stomach — or bedtime

Hormones & diabetesStrong evidence

Prednisolone / prednisone

Deltasone, Pred Forte (oral forms)

Morning

Hormones & diabetesStrong evidence

Metformin

Glucophage, Glucophage XR

With meals (XR with the evening meal)

Hormones & diabetesStrong evidence