Thursday, October 21, 2010
One evening, in the early summer of 2008, a Colorado sheriff's deputy named Jonathan Allen came home to find that his wife had made him a "special" dinner. Waiting on the table was his favorite spicy spaghetti dish and a big leafy bowl of salad.
As he told investigators later, some of those leaves in the salad were startling bitter. But his wife told him it was just a spring mix. He assumed it contained another of those trendy herbs that people use to liven things up. "Make sure you eat your greens," she added. "They're good for you."
So, he didn't worry when his toddler daughter tried to grab a bite and his wife, Lisa, reached out to stop the child. It was only a few hours later, when he was rushed to hospital suffering from severe stomach cramps and a wildly speeding heart, that he started to worry. And wonder.
After his stomach was pumped and the contents analyzed, Allen was no longer puzzled by his symptoms. The bitter taste was traced to leaves from a familiar and beautiful ornamental shrub, one growing in the family garden, in fact. Allen survived but he did not return to his home in the suburban Denver town of Golden, Colorado. He carefully stayed away while authorities launched an investigation into exactly how foxglove leaves got into the dinner salad.
And this year--about six months ago--42-year-old Lisa Leigh Allen pleaded guilty to felony assault, avoiding a trial for attempted murder with what The Denver Post called a "lethal plant." She was sentenced in mid-March to four-and-a-half years in prison.
A lethal plant is definitely one way to describe foxglove but--and, I have to admit, the description made me laugh--also definitely too simplistic. Yes, the foxglove plant is poisonous, but the very properties that make it poisonous also make it the source of some of our most important heart medications. I'll give that paradox away when I tell you that the common foxglove belongs to a family of plants with the Latin name of Digitalis. The plant that ended up in the Colorado deputy's summer salad is formally called Digitalis purpurea, but it also goes by some wonderfully evocative common names such as Witch's Glove, Bloody Fingers, and Dead Man's Bells.
Plants in the Digitalis family are packed with sugar-rich organic molecules called glycosides that can directly affect the rhythmic beat of the heart. The most important of these is called digoxin, or sometimes just digitalis, and is used to treat cardiac arrhythmias and to strengthen contractions of the heart. The knowledge that foxglove extracts affect the heart is nothing new--it was first reported in 1785 by a British physician named William Withering--but medical understanding of how it works is fairly recent.
For instance, digoxin (and a related compound digitoxin) are known to trigger a cascade of chemical reactions which increase the amount of calcium delivered to muscle cells. This increases the strength of the muscular contractions, thus giving new power to a weakened heart beat. Digitalis can also stimulate the nerves which regulate the internal pacing of the heart beat.
So, at the prescribed dose, digitalis is the opposite of lethal--a life-saving compound, in fact. But the proper dose is extremely small, and the body sounds warning bells if digitalis levels get too high. Early symptoms include nausea, stomach cramps, headaches and even hallucinations. It won't surprise you to know that the worst effect of digitalis poisoning is on the heart--its powerful effect on the heart muscle varies, depending on the individual, but an overdose can either slow the beat to a complete halt or speed it to a point of lethal over-taxation.
Thus, Jonathan Allen's early warning symptoms--the stomach cramps, the acute nausea, the racing heart beat--added a little more evidence to the case against his wife. The prosecution was also helped by searching her computer's hard drive, where investigators found a search history for foxglove, digitalis, and the homicidal possibilities. "I couldn't fathom that my wife was trying to kill me," Allen said during his wife's sentencing hearing. He was writhing with pain shortly before calling for an ambulance: "I went to bed and laid next to her. She said, 'It's probably just stress from your job.'"
Testimony in the sentencing hearing also detailed a very troubled marriage. Lisa Allen and her father testified that her husband was possessive and physically abusive and he had warned her that she would never be able to leave. Jonathan Allen said she and her family had been telling such lies about him for years. Even the judge finally wondered out loud why the couple hadn't separated, as both of their families had urged earlier.
It would have been, after all, a much better option than mixing up a heart-stopping salad.Tweet