How do guinea pigs sleep — is sleeping with eyes open normal?

Short answer: yes. They take many short naps of a few minutes and often sleep with their eyes open.

1. Rhythm — most active at dawn and dusk, and they keep nibbling hay at night.

2. Eyes open — a prey-animal instinct; closed eyes or lying on the side means they feel very safe.

3. Quiet setup — provide hideouts and avoid bright light or noise all night.

4. Night hay — top up hay before bed to maintain normal gut motility overnight.

5. Watch for — hunching all day, being hard to rouse or not eating means a prompt vet visit.