COCAINE POISONING.--Certain patients show an idiosyncrasy to the action of cocaine, and the greatest care must be exercised in its use. Absorption of small quantities usually causes mental excitement. The patient becomes restless and garrulous, and a feeling of happiness may be produced, but in other cases the patient becomes anxious and confused. In some patients a small dose is followed by a calm languorous state, resembling that produced by morphia, but with less tendency to sleep. The pulse is accelerated, the respiration is quick and deep, and the pupils are dilated. When poisonous doses have been administered, the heart becomes extremely accelerated, powerful tonic or clonic convulsions supervene, the breathing becomes rapid and shallow, and may be finally arrested during a convulsion. In some cases a different set of symptoms are observed, fainting and collapse occur, and convulsive seizures are almost entirely absent. The heart is slow and and weak, the respirations are slow and shallow, the skin is cyanotic and cold, and death takes place from gradual arrest of respiration. TREATMENT.--The treatment consists in endeavouring to encourage the action of the heart by every possible means. The patient is placed flat on his back, if he is not already in this position, hypodermic injections of ether and strychnine are administered, and hot coffee given by the mouth; warmth is of great importance. Artificial respiration is commenced if respiration begins to fail. There is no specific antidote to cocaine. DOSAGE.--The maximum dose of cocaine that can be given with safety is ¾ of a grain. The amount of solution that may be employed depends upon the strength. To make a 1 per cent solution, 1 gr. of cocaine hydrochloride is dissolved in 110 minims of distilled water or half strength normal saline; from these proportions the amount of cocaine in a given solution can be calculated. It will be seen that the amount of cocaine solution, even with strengths as weak as ½ or ¼ per cent, that can be used with safety is small and insufficient to anæsthetise an area of any great extent. Owing to its toxicity cocaine has largely fallen out of use for the production of infiltration or regional anæsthesia, though it is still widely used in ophthalmic surgery and in the surgery of the ear, nose and throat. Novocaine. This drug is immensely superior to cocaine for ordinary surgical purposes. It is the hydrochloride of a synthetic base, its chemical formula being C_{13}H_{20}N_{2}O_{2}, HCl. It is soluble in water 1 in 1, and can be heated to 120°C without decomposition. Its solutions possess slight antiseptic properties, and are capable of repeated boiling without affecting their strength. They may be kept for several months without suffering any change in their action, a quality not possessed by any other anæsthetic agent.