Fake fireplace and headaches

[Anonymous]

Sometimes I wake up in the morning with a big headache, almost like a hangover. It seems to happen sometimes when I turn up the heat, but not always.

It occurred to me that sometimes on a cold day, in the evenings, we'd have the fireplace on. It's below our bedroom. I haven't tested this theory out yet because I just thought of it today, but is there a possibility of causation between fireplace on in evening and headache the next morning, and if so, why and what to do about it?

It's a pretty new house we are renting, fwiw.

TIA

[Anonymous]

Carbon monoxide poisoning? Do you have a detector?

[Anonymous]

Yeah I'd get a detector.

http://www.abe.iastate.edu/extension-and-outreach/carbon-monoxide-poisoning-unvented-gas-space-heating-appliances-aen-204/

[Anonymous]

It could also be dehydration from the dry furnace air.

[Anonymous]

If it's not a vented fireplace, it could be from carbon monoxide.