Anna Faris Was Saved from Carbon Monoxide Poisoning Over Thanksgiving: I'm 'Very Fortunate'

Anna Faris has at least one more thing to be thankful for after a scary encounter with carbon monoxide on Thanksgiving.

The actress, 43, celebrated the holiday at a rented vacation home in Lake Tahoe, California, with family last week, when several guests complained of feeling ill. The group of 13 at first wrote it off as potential altitude sickness, the North Tahoe Fire Protection District said in a press release.

Two guests headed to the hospital, where carbon monoxide was determined to be the culprit. That’s when first responders were called to check up on the other 11 guests.

After inspecting the rental home, the safety crew said the living space had more than six times the maximum recommended indoor carbon monoxide levels — even with windows and doors open for ventilation.

Everyone was then treated for their symptoms, and two more were taken to the hospital for care.

Thanking the first responders for helping her family, Faris described the incident as “stupidly dramatic” in a tweet on Friday.

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“I’m not quite sure how to express gratitude to the north Lake Tahoe fire department- we were saved from carbon monoxide- it’s a stupidly dramatic story but I’m feeling very fortunate,” she wrote, sharing a photo from inside the house’s dining area.

First responders said the family is “lucky to be alive.” The source of the gas was not identified, and the residence did not have carbon monoxide alarms installed.

“We are so thankful to report that this holiday disaster was averted,” Mike Schwartz, fire chief for North Tahoe Fire, said in a statement. “Situational awareness is so important. Whether you are at home or traveling, it is important ensure that smoke and CO alarms are in working order anywhere you stay.”

He added: “It’s not a bad idea to consider bringing your own alarm when you travel, just to be safe.”

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Often nicknamed the “silent killer,” carbon monoxide is an odorless, colorless gas that, when inhaled, deprives the blood stream of oxygen, effectively suffocating victims. Common symptoms include dizziness, headaches and nausea.

The toxic gas kills hundreds of people each year, says the Centers for Disease Control, which recommends installing battery-operated alarms near sleeping areas, as well as having regular inspections of furnaces.

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Faris documented her entire Thanksgiving day preparations on Twitter prior to the health scare.

“1145 am. Rented house for family so we could have rooms. You know, to make love in. Which always happens during the holidays. Mom is concerned we don’t have enough garbage bags,” wrote the Overboard actress in her first of the live updates on Wednesday.

She later joked: “1153am. Hiding in the bathroom for just a minute. Choice between onion chopping, walk with family, or pretending my stomach is upset. My dad also wants to show me videos on YouTube.”

At around noon local time, Faris shared a photo of her father and brother on the couch, sarcastically quipping they were “hard at work.”

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Faris’ 7-year-old son Jack spent Thanksgiving with his father, Faris’ ex-husband Chris Pratt, as they gathered with the family of Pratt’s wife, Katherine Schwarzenegger.

The last of Faris’ Thanksgiving play-by-plays leading up to the carbon monoxide incident came on Thursday at about 11 a.m. PST.

“1113am. Could not find giblets or jiblets and my hand is very cold (but I did santitize). Now in bathroom hiding. Also my family is reading these tweets and I’m getting a touch of grief,” she wrote. “Dear family on the day of thanks-I love you all. Just a little more from the upstairs bath.”