In this malady, in my experience, a purin-free dietary offers the best chance of a cure, and two of my cases after years of suffering have quite got rid of their attacks. In neither case, however, was the diet absolutely purin-free, although the rules laid down by Haig otherwise were carefully followed - viz., (1) that a minimum of fluid be taken, (2) that the bowels be kept open extremely well; and I added a third instruction, to avoid all salt in the food, replacing it in the bread used by a small quantity of sodium bromide. A third case has now been under treatment for nine years without having had a single attack, as compared with one every three months before that; the only purin-containing food allowed is 6 oz. of some kind of animal food once daily. This case, as well as the three I am about to mention, has had in addition each day, for the first two years of the treatment, 10 minims of tincture of digitalis and 20 grains of sodium bromide. These three cases, on a limited purin-free diet, had not a single bad symptom during their course of treatment, differing markedly from the next three on a purin-free diet.

These three cases, the details of which it is quite unnecessary to publish, unquestionably for a time derived considerable benefit from the adoption of a rigorous purin-free diet, and just at first their epileptic attacks were distinctly reduced in number; but after a variable interval - nine months in one, eighteen months in another, three years in a third - each one was attacked with indications of severe physical debility: muscular rheumatism in one, nasal catarrh, indigestion and amenorrhcea in another, with anaemia and great physical exhaustion in all three, and coincident with this breakdown in health in two of them, the attacks of epilepsy recurred as badly as ever. The third case has had no further attacks of epilepsy, but remains in her exhausted condition, although she considers the freedom from epilepsy cheaply purchased by the substitution of her other maladies.

In common with all my other patients on a purin-free diet, these three felt the cold severely. Two of them, however, are so convinced of the value of the diet in their malady, that they insist on persevering with it for a longer period, and as I am quite certain of at least the temporary value of such a mode of dieting in most chronic maladies, I have encouraged them in this desire, although from experience I expect a recurrence of their trouble in perhaps a less aggravated form. This great reluctance to give up a fleshless diet after it has been persevered in for months or years is a special feature in many cases. Some of them seem to think there is a special virtue in carrying out such a regimen, and although they do not quite look upon themselves as martyrs in a good cause, they have a sense of importance which is almost religious in its fervour, and which is much intensified when they lose all taste for animal food. This the vegetarian takes to be an absolutely certain proof that his is the only natural diet, forgetting that it is quite possible to find people who have in similar manner lost all taste for fruits and nuts.

It is a notable fast that after having been on a purin-free diet for a lengthened period, a return to mixed diet is often followed by bad results, due to the loss of digestive power from disuse, and other causes, but not necessarily due to the purins. Meat juices and gravies, probably owing to the purins they contain, are strong peptogenic agents, being the strongest stimulants to the digestive powers which we know, but, like all stimulants, in excessive quantities they are apt to exhaust the functions to which in small quantities they are valuable adjuvants. Each food has its own special peptogen or digestive stimulant, which acts best when the stomach is for a short time accustomed to its stimulus, but when deprived of it for some time, it does not at once respond to its peptogenic properties. This I believe to be the explanation of the bad results of resuming a mixed diet after a temporary deprivation.

I am sure that quantity of food has much to do with the attacks of epilepsy, as it is a common thing for such patients to remark that an increase in weight is the prelude to an attack, and they are almost invariably correct. The only certain fact we know in the pathology of epilepsy is the instability and proneness of the cortical cells to discharge their energy; and increased blood supply is a highly probable factor in this irregular discharge of nervous energy. Purins in the blood may act as irritants, but it is much more likely that they stimulate the appetite, especially for nitrogenous foods, which are the chief source of nerve energy, and in this way precipitate an attack. Total deprivation of purins seems so to disorder the digestions of those once accustomed to them that toxaemia is produced, and this of itself is apt to set up convulsions. Where, however, a good digestion, not spoiled by years of bromide administration, exists, a purin-free diet, especially in recent cases, will be found most valuable, and even in confirmed cases of the same type will diminish the frequency or severity of the attacks. In the average case, however, a diet without free purins, but only those contained in a small quantity of the accustomed animal food, will be found more suitable.