Their action upon the secreting system is not very uniform, nor are all writers agreed as to its nature. Opium generally checks most of the secretions, except that of the skin, and causes heat, thirst and con stipation. Hyoscyamus rarely causes any of these states, but on the contrary is rather laxative, and aconite greatly increases the secretion of the bile and also of the skin. Many natural compounds have an acrid principle combined with the narcotic, and hence are termed narcotico-acrids, such as aconite, squil, colchicum, hellebore, &c. : these generally augment the mucous and other secretions, though they pro duce narcotism in excessive doses.
Lastly, some of them possess greater influence over one set of nerves than the other, and expend their energy on the nerves of motion, or of sensation, according to their nature.
No set of medicines have their action more modified by a variety of circumstances—such as the quantity given, or the frequency of repeti tion, also the force of habit, climate, or season, but above all by idiosyncrasy. Age also has an important share in determining the amount of action. Children do not in general bear them well, and therefore though they are very subject to convulsive and spasmodic diseases, other means should be employed, especially the removal of the source of irritation, when practicable. The various nostrums recommended for children generally contain some narcotic, and prove a fertile cause of the mortality of early life. [A.NrrsrAsmonws.] The administration of narcotics requires more knowledge and judgment than that of any other class of remedies, and shoal only be had re course to under competent advice.
In ease of over-dose or accidental poisoning, the following observa tions may be tueful. The stomach being rendered insensible to the irritation of emetica, these are generally useless, and much valuable time is lost by administering them. Where better means cannot he bad, sulphate of zinc (white vitriol) dissolved in water, or a table spoonful of flour of mustard diffused through a pint of warm water, may be given, accompanied with pressure on the pit of the stomach, and at the same time tickling the throat with a feather. Neither
ipecacuan nor tartar emetic should be used ; the latter is particularly unfit. [Bem.snoxxa.] The stomach-pump is the surest means of emptying the stomach, and should be used as soon as possible. If the brain appear much oppressed, the countenance flushed, and the pulse full, 'moderate blood-letting will be serviceable, especially if artificial respiration be subsequently employed. When the water brought up by the stomach-pump is clear and devoid of any smell of the poison, which will prove that all the hurtful material has been evacuated, Men, and Not till Men, vinegar may be given to the patient, who should also be kept moving about, and not suffered, if possible, to sink into a s(ato of slumber. Coffee is a very useful beverage, and still more a drink made by boiling twelve ounces of vinegar, and pouring it immediately on three ounces of roasted and ground coffee, or by boiling the coffee in the vinegar, straining it, then adding half an ounce of sugar, and giving it in small quantities to the patient every quarter or half hour. This can be prepared while the stomach-pump is being used, and is one of the most efficacious means of counteracting the narcotic prin ciple. Vinegar given while any of the poisonous substance is in the stomach only increases its deleterious property. [As•rtnovEs.] See Materia Iledica; for the mode of action of the different narcotic substances, i., p. 200 ; and Christison ' On Poisons.' The s-apoturs of several fluids, such as sulphuric tether, chloroform, amp line, &c., have been used to produce insensibility, particularly during surgical operations. These have been already treated of under