At three in the morning a ward sounds different. A pump alarms and is silenced. The man in bed four is awake and pretending not to be. The registrar on call eats biscuits standing up at the nurses' station, and in the corridor a daughter sits in a plastic chair, waiting for daylight to make things clearer.

This month's word is Nights.

Write us the night shift, or the night before a scan when sleep wouldn't come. The night a patient died, or the night a child's fever finally broke. The long dark of an illness that made every night the same. If the word takes you somewhere else, follow it.

Up to 300 words, prose or poetry. You don't need to have published before or to call yourself a writer. You need only something true to say about the night.

At the end of October we'll gather the pieces that move us into one collection, so they can be read as they were written: side by side, by people who have all sat up in the dark.

How to take part

• Send your piece by 31 October to narrativesmedicineheart@gmail.com, with the subject line "In Common: Nights".
• Up to 300 words, one piece per person.
• Tell us how you'd like to be named (full name, initials, or unnamed) and add a short line about who you are.
• If you write about a real patient, protect their privacy: ask their consent, or change the details that would identify them.

We read everything, and we reply.