Manual of dispensing, 1938 / War Office.

Date:
1938
Catalogue details

Licence: Public Domain Mark

Credit: Manual of dispensing, 1938 / War Office. Source: Wellcome Collection.

    61/394 (page 49)
    Poisoning of an Unknown Nature Symptoms of poisoning are frequently conflicting, and occasionally it may be impossible to ascertain what kind of poison has been taken. This is likely to be the case when some rarely used poison has been taken, or when some com- mercial compound or drug, symptoms of poisoning by which are not well known, has been swallowed. Again, in the very early stages of poisoning, it may be difficult to recognize the poison by the uncertain symptoms shown; indulgence in alcoholic liquor may cloak the symptoms and hinder diagnosis. In such circumstances it is useful to have at hand a general antidote which is calculated to do good whatever the poisoning may be. A recipe for such an antidote is : Calcined Magnesia \ Powdered Charcoal pEqual parts of each. Hydroxide of Iron J Half an ounce (one tablespoonful) of each should be stirred into a tumbler of water and administered as a draught. The dose may be repeated at intervals of half an hour until three doses have been given. The iron hydroxide should be freshly precipitated by mixing a solution of ferric chloride (Liquor Ferri Perchloridi) with lime water or a solution of ammonia, and shaking. A thick precipitate is obtained which should be strained or filtered out and washed, before mixing with the other ingredients. A suitable method of obtaining the precipitate quickly is to pour the mixed solutions into a large handkerchief and, when the fluid portion has drained away, hold the handkerchief under a running tap for a minute or two to wash the sediment. Each of the ingredients of the antidote has its own particular part to play in counteracting poisoning. The calcined magnesia (magnesium oxide) has a threefold action: (i) it is alkaline, and is capable of neutralizing free acids ; (ii) it will interact with many soluble metallic salts and render them insoluble ; (iii) it tends to render alkaloidal preparations insoluble, and so prevents, or at any rate retards, absorption. Charcoal is completely insoluble and, being in a very finely divided state, adheres closely to the lining of the stomach and hinders absorption of the poison. At the same time finely powdered charcoal has that property (known as adsorption) of condensing certain toxic substances on the surface of its particles and rendering them temporarily inactive. Hydroxide of iron is the specific antidote for arsenical poisoning.