Psychiatrymiddle twist
A 24-year-old man is admitted at 11 pm with a first episode of psychosis. He has had six weeks of persecutory beliefs and voices commenting on his actions, and has lost 6 kg. He is settled on the ward and willing to take medication. Physical examination, including neurological examination, is normal, and he is fully oriented. Your registrar asks you to start olanzapine tonight and to organise the first-episode work-up. Every option below belongs in that work-up. Which one must be completed before the first dose is given?