Digitalis is a very effective poison given that it is readily available and lethal in very small quantities. But before you start plotting the demise of your enemies, it is worth noting that digitalis is also detectable in very small quantities.
Digitalis refers to compounds extracted from foxgloves which have specific and dramatic effects on the heart . Digitoxin is one such compound ; it has a serious effect on the heart because of its ability to dampen the electrical signals that coordinate the contractions of the cardiac muscles. In low doses, this causes arrhythmia (an irregular heart beat). However, in higher doses, digitoxin can completely block electrical signalling – effectively paralysing the heart.
Interestingly enough, atropine (a different toxin) can be given to stimulate the heart and work as an antidote to digitoxin poisoning or overdose.
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