INSOMNIA.
The different types of insomnia are difficult to classify. Secondary of symptomatic and primary insomnia are accepted as embracing all cases of sleeplessness. The primary division includes the insomnia due to psychic causes such as mental excitement, grief, worry, brain fag and that to be met with in the neurotic and psychopathic strains which manifest neurasthenia, hysteria, hypochondriac tendencies. or other latent affinities with melancholia and the different types of insanity. This primary class will also include the large group of toxic insomniac. This group, however, overlaps those included in the secondary or symptomatic division of sleeplessness in which the insomnia is the result of some primary diseased condition as fever, pulmonary, cardiac or renal disease where the exciting cause of the wakefulness is often toxic. Hence in the treatment of insomnia little aid is to he expected from a rigid classification of its different types, the wisest course in each case being to institute a careful search for the primary cause upon the removal of which the success of all rational treatment depends. It must also be remembered that in a neurotic individual a trifling symptomatic or secondary cause may induce severe insomnia, whilst the same factor is harmless when present in an individual possessing a more stable nervous system.
Thus severe insomnia may be produced in some neurotic individuals by a cup of tea taken late in the evening, by the presence of some trivial personal discomfort as coldness of the feet, or by any sudden change in the hours of diet; some patients cannot sleep after a late supper, whilst others fail to get any sleep if they retire to rest with their stomachs empty. Sleep may only come to those who retire to bed immediately after wearying the brain with active exercise. Others may be wholly unable to sleep if any previous mental activity has been indulged in. It is a common experience to find amongst active brain workers that sleeplessness follows after taking a day of rest and calm, and often the freedom from care and the repose of the Sabbath result in the loss of sleep for the night, whilst insomnia often seizes the clergyman after his severe day of exciting mental strain.
A common variety of sleeplessness described by the writer under the name of habit insomnia is met with in which no immediate cause is discover able, the affection having been originally produced by an exciting cause long since removed, and the patient has acquired the habit of lying awake. The mere dread of not sleeping is a powerful factor in such cases when the idea presents itself to the mind of the patient after retiring to rest. The rhythmic nature of the natural sleep process must always be kept in mind ; when this rhythm is broken by any serious change in the hour of taking rest a troublesome habit insomnia may develop; the individual lies awake till the usual sleeping hour arrives, and the conditions being then so different from those associated with his former regular sleeping hour that sleep does not supervene.
Under the different headings in the present volume the sleeplessness associated with each disease is referred to amongst the complications of the affection. The aim of all treatment should be the removal of the primary cause as dyspepsia, gouty conditions, cough, pyrexia, pain, pruritus, dyspncea, failing compensation, obstinate constipation, &c. This should be undertaken in every instance before resorting to the routine administra tion of hypnotics, though the use of these in some cases is imperative when the cause is not capable of being removed, and in many cases even after the causal factor has been dealt with, should habit insomnia have developed. A word of caution is, however, necessary in dealing with narcotics; when pain is the immediate cause of insomnia ordinary hypnotics are useless, as sleep will not supervene till the pain has been relieved by morphia or opium. Prohibition of these drugs is necessary when the cause of the pain is irre movable, as the opium habit is certain to become established if the drug is employed as an hypnotic, and the same remark applies to alcohol.