digitalis in fox glove plant

[lord molly]

how is this extracted 4 use in modern medicine?

thanks dudes, u rule!!!!!!!!!!!

lord molly out!!

[theprof]

There a quite a few methods used.

Solvent extraction using ethanol is the most prevalent method. Pyridine is also sometimes used in the same process.

There are also a number of patented extraction methods used including supercritical fluid extraction and even methods based upon enzymatic extraction. Most of these patented methods to date are not really suitable for mass extraction of digitalis and solvent extraction has been the best practical method since the 1930's.

Digitalis is a crude drug and is a mixture of a number of cardiac glycosides. Digoxin is the most frequently prescribed digitalis glycoside and is isolated from digitalis using various methods including precipitation. Digitoxin is another glycoside present in the leaves.

[lord molly]

how dangerous is digitalisif consumed?

[theprof]

OK, as I said yesterday, digitalis is made up of a number of cardiac gIycosides and toxicologists prefer to discuss the toxicity of digitalis in terms of the two main components, namely digitoxin and digoxin. Let's deal with them one at a time.

Digitoxin is regarded as super toxic. Now this may seem a pretty vague term for a scientist to use, but believe it or not, it's an official classification of toxicity amongst toxicologists and is the next step up above extremely toxic. Ingestion of toxic quantities of digitoxin causes nausea, vomiting, drowsiness, disorientation, hallucinations, weakness and fatigue amongst other symptoms. Visual disturbances also arise such as flickering lights or changes in colour vision. Digitoxin is capable of causing cardiac arrhythmias and electrolyte imbalances in the body and these may well lead to fatality. Death actually occurs because the heart goes into ventricular fibrillation and then cardiac arrest. In humans, the lethal dose is usually between 3mg and 10mg.

Digoxin is also regarded as super toxic and digoxin poisoning causes almost identical symptoms as digitoxin. Oddly, from a diagnostic point of view, digoxin poisoning generally causes convulsions whereas convulsions are rare in digitoxin poisoning. Most toxicologists will give you a figure of less than 5mg/kg as the human lethal dose.

[lord molly]

i won't go licking my fox gloves then

[theprof]

Better Not.