Antagonists - Antidotes

Hydrate of magnesia, or of lime, will neutralize the acid compounds of phosphorus, and carbon will absorb phosphorus vapor. Sulphide of carbon antagonizes the excitant action of the drug, as also do sulphuretted hydrogen, anaesthetics generally, and cyanides (Gubler). Nitrate of silver was recommended as antidotal by Bellini (Medico - Chirurgical Review, ii., 1875).

In an important experiment by Crocq, oxygen was used as an antidote, defibrinated blood charged with the gas being injected into the veins, with the effect of restoring to its normal condition the dark, pitchlike blood of poisoned animals (British and Foreign Review, ii., 1875).

But the two antidotes which claim special attention are sulphate of copper and oil of turpentine. With any soluble salt of copper, phosphorus forms a black phosphide, non-poisonous; and as copper sulphate is also a good emetic, it is specially available for cases when the poison has been taken by the stomach, and when the remedy can be given soon afterward. Five grains should be given every two or three minutes until free vomiting is induced, and then, either continued in smaller doses and with opium, or turpentine may be substituted.

If oil of turpentine be brought into contact with phosphorus at a suitable temperature, a crystalline white solid is formed - terebinthino - phos-phorous acid - which is not poisonous. Kohler and Schimpf obtained it by adding gradually 2 lbs. of the oil to 3/4 oz. of the element at 40° C., and the same substance has been obtained in the distillate from urine in cases of poisoning (Pharmaceutical Journal, March, 1873). To produce the desired result, the oil must come into direct contact with phosphorus in the stomach, and in the proportion of about 100 parts to each one of the latter. Eleven hours is the longest time that has elapsed before the administration of the remedy in successful cases. Moreover, it is not every kind that will act well; the pure rectified oil, and much of that imported as German and American, do not form the crystalline acid, and hence a difference in the results of some observers. It is the crude, acid, French oil, or that which has been ozonized by long exposure, which gives reliable results. It is said also that milk lessens its good effect.

A case illustrating the value of both the antidotes recommended occurred in my practice some years ago. A young man (insane from over-study for examination) swallowed some pieces of solid phosphorus, and, while his friends were gone for assistance, gashed his throat and body with a razor. When I saw him the most pressing need was to stay hemorrhage, and while doing this I sent for some copper sulphate and turpentine, giving him at once mustard and water. This and the copper produced good emesis, with rejection of a piece of phosphorus two inches long. I then began giving turpentine in milk (also in water), but still encouraged vomiting, because from the small pieces left in the patient's bottle of phosphorus more was thought to have been taken. Eventually two other pieces, 1 1/2 in. and 1/2 in. long, were rejected, after having been in the stomach at least three hours. Several more doses of turpentine were given, and the patient made a good recovery, with the exception of some dyspepsia: he was seen afterward by Dr. Fuller, the family physician, and passed from under my care, but is, I believe, still living in an asylum. The case may be considered another illustration of the fact that large pieces of phosphorus are less dangerous than the finely divided substance; but I think real benefit resulted from the antidotes used.

A case is reported of a man who swallowed 120 match-heads, and then took turpentine to increase the effect. He did not vomit, but recovered (Medico - Chirurgical Review, ii., 1869, p. 555).

Other cases, cured by the same antidotes, are given in Braithwaite, i., 1872, p. 131, and in Sydenham Society's "Year Books," and British Medical Journal, i., 1878.

Therapeutical Action (Internal)

From what has preceded, it will be recognized that the value of phosphorus lies in its power of strengthening and giving tone to the nervous centres when their activity is impaired; also, since nerve-debility is a cause of many other besides what are called nervous diseases, a nerve-tonic of this kind has a wide field of usefulness, and is applicable not only in nerve-exhaustion and pain, but in many conditions of adynamia. Rabuteau, however, states an opposite view when he says: "I do not hesitate to assert that this poison has never cured anything up to the present time, and I would never prescribe it; it has always been useless" ("Elements," p. 211); while Beaumetz, A. Thompson, and others have recorded wonderful results from it. The truth probably lies between the two extremes, and we must not forget that some failures may be accounted for by inactive preparations of a drug always difficult to dispense.

Preparations And Dose

Phosphorus: dose, 1/100 to 1/10 gr., less or more. Oleum phosphoratum (made with oil of almonds previously heated to 300° F., to destroy organic impurities); 5 min. contain 1/32 gr.: dose, 3 to 10 min. Pilula phosphori (made with tolu and yellow wax); 5 gr. of the pill contain 1/18 gr.

An exception has been taken to these officinal preparations: to the oil as disagreeing with the stomach, to the pill as being too concentrated, or not soluble enough; and many other formulae for the medicine have been published (British Medical Journal, i., 1879, etc.). It is commonly agreed that the free unoxidized element will produce effects which none of its chemical compounds can do, and it is desirable, therefore, to give it in its pure, unaltered state. It cannot be finely divided without risk of oxidation, and the vehicles of fluid preparations, especially oils, are apt to disagree with the stomach.

Devergie, Solon, and others state that a solution in any vegetable oil, exposed to light and air, is apt to decompose, with partial conversion of the element into hypophosphorous acid, which has toxic properties, and hence some untoward accidents that have occurred with the phosphorated oil. A solution in cod-liver oil is not liable to this, but Dr. Broadbent finds it soon becomes oxidized, and loses its effect.

An alcoholic tincture may be prepared by adding phosphorus in excess to boiling alcohol quite free from water; this will take up 1 gr. in 6 dr. 20 min. (Thompson), and, if carefully kept from light and air, will remain unchanged for some weeks. As the result of many observations, Dr. A, Thompson recommends 3 dr. 10 min. of this tincture (=1/2 gr. phosphorus) to be added to 1 oz. 40 min. of anhydrous glycerin, with 5 min. of spt. peppermint, and he finds this more stable and less disagreeable than any other form.

I myself prefer an ethereal tincture, in which 1 gr. phosphorus is first dissolved in 1 dr. of pure ether; and this solution, after standing some days, is mixed with pure alcohol, so that a proportion of 1 gr. in 500 min. is preserved. From 2 1/2 to 5 or 10 min. of this (1/250 to 1/100 or 1/50 gr.) are readily taken, mixed with water, and the preparation is stable enough for all practical purposes. It should not be kept longer than three to five weeks.

Chloroform, which dissolves 1 per cent. rather quickly, has been used by M. Beaumetz as a vehicle, in capsules or in wine; but it is nauseous, and not well borne. Bisulphide of carbon is really the best solvent yet known for phosphorus, but its depressant and sometimes toxic effects contra-indicate its use. Water will take up, after agitation, a minute but uncertain amount of phosphorus, and it is not practically available as a medium for it. Capsules or "perles," containing 1/50 to 1/30 gr. in the form of phosphorated oil, are carefully prepared by Morson and other eminent pharmacists, and have been preferred by many physicians. They should be given after meals, but, even so, are not free from risk of causing gastric irritation. Pills may be made either with the drug reduced and powdered, or with a solution. Mr. Batten recommends pills with white wax; Mr. Gerrard with resin; Dr. Radcliffe uses suet. I do not like the pilular form; but, if it be adopted, oleum theobromae is the best medium, though not easy to manipulate (Martindale).

The phosphide of zinc is a good form for administering in pill. Lemonade should be given at the same time. Dose: 1/20 gr. to 1/2 gr. The latter dose may nauseate.

[None of the foregoing preparations have as yet been admitted into the U. S. Pharmacopoeia.]