Topic: About barbiturates in The Mirror Crack'd by Agatha Christie (Read 25809 times)

Lord Drol · « **on:** September 12, 2017, 02:44:22 PM »

Hello.

In the Angela Lansbury version of Agatha Christie's The Mirror Crack'd, Calmo (a fictional branded barbiturate) is switched for phenobarbital.

Heather Babcock/Badcock dies because of an overdose of phenobarbital that's dissolved in an alcoholic drink that she later drinks.

How many tablets could've killed her?

What in milligrams per tablet were available?

I ask out of curiosity, that's all.

And it's one of my favourite Agatha Christie stories.

Dave Freas · « **Reply #1 on:** September 12, 2017, 04:18:36 PM »

There are no absolute answers except for the strength of the phenobarbital tablets. When I was an active pharmacist (I've been retired 8 years now) they were available in 15, 30, 60, and 100 mg strengths.

The answer to you other question is 'It depends.'

How many tablets would kill Heather depends on the strength of the tablets. What’s critical though is not the strength of the tablets but the total dose of phenobarbital she gets. Reference books say 2 to 10 Grams of phenobarbital is a lethal dose, which equals 20 to 100 100mg tablets. Obviously, it would take many, many more 15mg tablets than 100mg ones.

If she's 90 Lbs. it will take a lower total dose of phenobarbital than if she’s 165 Lbs. If she’s young and healthy, it will take more than if she’s older and has health problems. If she has breathing problems like asthma, COPD, or something similar, a lower dose will do her in through respiratory depression. If she’s eaten a meal before drinking the phenobarbital-laced drink, it will take more drug (and a longer time) to kill her off than if she downs it on an empty stomach. The size of the meal and its composition will affect it too. A large heavy meal will keep her alive longer than a saltine topped with a dab of pate.

Lord Drol · « **Reply #2 on:** September 12, 2017, 04:42:19 PM »

Thank you for replying, Mr Freas.

Your experience and knowledge helps me to understand more how Heather's death could've happened, and why.

Also, I'm fascinated by drugs/poisons in murder mystery stories.

Lord Drol · « **Reply #3 on:** September 17, 2017, 06:11:36 PM »

A theory that might explain the ambiguity about a death in Agatha Christie's A Murder Is Announced.

Contains SPOILERS

In the book - Dora Bunner (who's 64 years old) was poisoned with an unnamed narcotic. Annoying! (I assume she took barbiturates?) The "story" is: Dora took tablets from an aspirin bottle (for a headache) that were in her friend's room (Miss Blacklock's) - and later, Dora dies in her sleep.

Earlier Dora tells of not knowing where her own new bottle of aspirin tablets are. Miss Blacklock, opportunistically, tells Dora to use the aspirin in her bedroom.

Theory: Miss Blacklock (a little bit later) followed Dora. Dora still hadn't found her tablets so Miss Blacklock went and got her "aspirin" and gave them to Dora. A couple of tablets. After that, Miss Blacklock engineered them having an alcoholic drink each? With more barbiturates dissolved in Dora's glass? Because Dora's 64 (and frail), the doses were enough for Dora to die later in her bed. After leaving Dora alive, Miss Blacklock emptied the real aspirin out of her bottle, putting barbiturates into it as replacements? Miss Blacklock wanted Dora's death to appear as accidental, that Dora took the swapped tablets by mistake. That Miss Blacklock was the intended victim.

In the book Miss Blacklock stole a gun from a neighbours' house to kill someone. So she saw other people's prescriptions and stole them too?

Dave Freas · « **Reply #4 on:** September 17, 2017, 07:47:08 PM »

In Agatha Christie's day, it probably actually was a narcotic of some kind. Doctors were more, um, liberal in their dispensing of narcotics, in part because that was all they had for pain relievers and the one's they had were nowhere near as potent as the ones we have now.

If you read a lot of books set before, oh, say 1950, you'll notice that they never (or almost never) use real drug names or poisons. I think they were afraid of someone doing in someone else the same way. Plus if they made up the drug or poison, they could give it whatever properties they wanted. It was only after WWII that they started calling a poisonous spade a poisonous spade.

Lord Drol · « **Reply #5 on:** September 18, 2017, 10:27:47 AM »

Mr Freas, I understand Agatha wouldn't have wanted to signpost methods to help her readers commit murder hence her ambiguity about (and fictionalising of) drugs in her books.