Allen took to her Twitter.com blog on Tuesday morning and told fans, "Have the sorest throat ever. It's woken me up and I can't get back to sleep. Can't swallow, might die.
"Tres (very) excited for Chanel this morning. Sore throat no better though. Full on flu."
The singer succumbed to her sickness and returned home to the U.K. as soon as the runway show wrapped.