A Missouri woman accused of poisoning her husband has been charged with attempted murder, officials said Wednesday. 

The Jefferson County Police Department said in a statement that its officers investigated a call "involving allegations of intentional poisoning of a spouse" on Jan. 16. The victim told officers that he believed his unexplained illness was actually due to poisoning by his wife, identified by CBS affiliate KRCG as 37-year-old Sarah Scheffer. 

According to court documents reviewed by KRCG, the man said he was suspicious of his wife and thought she had been putting substances in his food and drinks for about six weeks. He experienced symptoms of fatigue, confusion, blurred vision, dry mouth and nausea. 

He also told police that he saw a bag labeled "Lily of the Valley" on a table in their home. He also saw a green bowl with what he said was a root from the bag. The man showed police a photo of the bowl, and a video of Scheffer making a smoothie using its contents. The man brought the smoothie to law enforcement. It was submitted to the Missouri State Highway Patrol Laboratory for testing. 

Police said in the news release that a "search of a national poison control center indicated all parts of the substance used contain numerous cardiac glycosides, which slow down the heart and cause irregular heart rhythm." The substance also could cause nausea, vomiting and abdominal pain. According to online information posted by Mount Sinai, lily of the valley can cause symptoms including lethargy, confusion, blurred vision and nausea, along with dozens of other symptoms. 

Police said that when they interviewed Scheffer, she admitted to putting lily of the valley in her husband's food and knowing that it was illegal and would cause harm. 

In addition to attempted murder, Scheffer has been charged with armed criminal action. 

Scheffer was arrested on Tuesday and booked into the Cole County Jail at 7:46 p.m.  

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• Crime

Kerry Breen

Kerry Breen is a reporter and news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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