Epileptic fits of this sort succeed each other with varying degrees of frequency, and occasionally, though not frequently, with regular periodicity. In some persons they only occur once in a lifetime, or once in the course of many years, while in others they return every week or two, or even are of daily occurrence, and occasionally there are numerous attacks each day. According to Sir J.R. Reynolds, there are four times as many epileptics who have their attacks more frequently than once a month as there are of those whose attacks recur at longer intervals. When the fit returns it is not uncommon for one seizure to be followed by another within a few hours or days. Occasionally there occurs a constant succession of attacks extending over many hours, and with such rapidity that the patient appears as if he had never come out of the one fit. The term status epilepticus is applied to this condition, which is sometimes followed with fatal results. In many epileptics the fits occur during the night as well as during the day, but in some instances they are entirely nocturnal, and it is well known that in such cases the disease may long exist and yet remain unrecognized either by the patient or the physician.

The second manifestation of epilepsy, to which the names epilepsia mitior or le petit mal are given, differs from that above described in the absence of the convulsive spasms. It is also termed by some authors epileptic vertigo (giddiness), and consists essentially in the sudden arrest of volition and consciousness, which is of but short duration, and may be accompanied with staggering or some alteration in position or motion, or may simply exhibit itself in a look of absence or confusion, and should the patient happen to be engaged in conversation, by an abrupt termination of the act. In general it lasts but a few seconds, and the individual resumes his occupation without perhaps being aware of anything having been the matter. In some instances there is a degree of spasmodic action in certain muscles which may cause the patient to make some unexpected movement, such as turning half round, or walking abruptly aside, or may show itself by some unusual expression of countenance, such as squinting or grinning. There may be some amount of aura preceding such attacks, and also of faintness following them. The petit mal most commonly co-exists with the grand mal, but has no necessary connexion with it, as each may exist alone. According to Armand Trousseau, the petit mal in general precedes the manifestation of the grand mal, but sometimes the reverse is the case.

The third manifestation—Jacksonian epilepsy or partial epilepsy—is distinguished by the fact that consciousness is retained or lost late. The patient is conscious throughout, and is able to watch the march of the spasm. The attacks are usually the result of lesions in the motor area of the brain, such being caused, in many instances, by depression of the vault of the skull, due to trauma.

Epilepsy appears to exert no necessarily injurious effect upon the general health, and even where it exists in an aggravated form is quite consistent with a high degree of bodily vigour. It is very different, however, with regard to its influence upon the mind; and the question of the relation of epilepsy to insanity is one of great and increasing importance. Allusion has already been made to the occasional occurrence of maniacal excitement as one of the results of the epileptic seizure. Such attacks, to which the name of furor epilepticus is applied, are generally accompanied with violent acts on the part of the patient, rendering him dangerous, and demanding prompt measures of restraint. These attacks are by no means limited to the more severe form of epilepsy, but appear to be even more frequently associated with the milder form—the epileptic vertigo—where they either replace altogether or immediately follow the short period of absence characteristic of this form of the disease. Numerous cases are on record of persons known to be epileptic being suddenly seized, either after or without apparent spasmodic attack, with some sudden impulse, in which they have used dangerous violence to those beside them, irrespective altogether of malevolent intention, as appears from their retaining no recollection whatever, after the short period of excitement, of anything that had occurred; and there is reason to believe that crimes of heinous character, for which the perpetrators have suffered punishment, have been committed in a state of mind such as that now described. The subject is obviously one of the greatest medico-legal interest and importance in regard to the question of criminal responsibility.

Apart, however, from such marked and comparatively rare instances of what is termed epileptic insanity, the general mental condition of the epileptic is in a large proportion of cases unfavourably affected by the disease. There are doubtless examples (and their number according to statistics is estimated at less than one-third) where, even among those suffering from frequent and severe attacks, no departure from the normal condition of mental integrity can be recognized. But in general there exists some peculiarity, exhibiting itself either in the form of defective memory, or diminishing intelligence, or what is perhaps as frequent, in irregularities of temper, the patient being irritable or perverse and eccentric. In not a few cases there is a steady mental decline, which ends in dementia or idiocy. It is stated by some high authorities that epileptic women suffer in regard to their mental condition more than men. It also appears to be the case that the later in life the disease shows itself the more likely is the mind to suffer. Neither the frequency nor the severity of the seizures seem to have any necessary influence in the matter; and the general opinion appears to be that the milder form of the disease is that with which mental failure is more apt to be associated. (For a consideration of the conditions of the nervous system which result in epilepsy, see the article [Neuropathology].)

The influence of hereditary predisposition in epilepsy is very marked. It is necessary, however, to bear in mind the point so forcibly insisted on by Trousseau in relation to epilepsy, that hereditary transmission may be either direct or indirect, that is to say, that what is epilepsy in one generation may be some other form of neurosis in the next, and conversely, nervous diseases being remarkable for their tendency to transformation in their descent in families. Where epilepsy is hereditary, it generally manifests itself at an unusually early period of life. A singular fact, which also bears to some extent upon the pathology of this disease, was brought to light by Dr Brown Séquard in his experiments, namely, that the young of animals which had been artifically rendered epileptic were liable to similar seizures. In connexion with the hereditary transmission of epilepsy it must be observed that all authorities concur in the opinion that this disease is one among the baneful effects that often follow marriages of consanguinity. Further, there is reason to believe that intemperance, apart altogether from its direct effect in favouring the occurrence of epilepsy, has an evil influence in the hereditary transmission of this as of other nervous diseases. A want of symmetry in the formation of the skull and defective cerebral development are not infrequently observed where epilepsy is hereditarily transmitted.

Age is of importance in reference to the production of epilepsy. The disease may come on at any period of life, but it appears from the statistics of Reynolds and others, that it most frequently first manifests itself between the ages of ten and twenty years, the period of second dentition and puberty, and again at or about the age of forty.

Among other causes which are influential in the development of epilepsy may be mentioned sudden fright, prolonged mental anxiety, over-work and debauchery. Epileptic fits also occur in connexion with a depraved stage of the general health, and with irritations in distant organs, as seen in the fits occurring in dentition, in kidney disease, and as a result of worms in the intestines. The symptoms traceable to these causes are sometimes termed sympathetic or eccentric epilepsy; these are but rarely epileptic in the strictest sense of the word, but rather epileptiform.

Epilepsy is occasionally feigned for the purpose of extortion, but an experienced medical practitioner will rarely be deceived; and when it is stated that although many of the phenomena of an attack, particularly the convulsive movements, can be readily simulated, yet that the condition of the pupils, which are dilated during the fit, cannot be feigned, and that the impostor seldom bites his tongue or injures himself, deception is not likely to succeed even with non-medical persons of intelligence.

The medical treatment of epilepsy can only be briefly alluded to here. During the fit little can be done beyond preventing as far as possible the patient from injuring himself while unconsciousness continues. Tight clothing should be loosened, and a cork or pad inserted between the teeth. When the fit is of long continuance, the dashing of cold water on the face and chest, or the inhalation of chloroform, or of nitrite of amyl, may be useful; in general, however, the fit terminates independently of any such measures. When the fit is over the patient should be allowed to sleep, and have the head and shoulders well raised.