Suppurative pleurisy, or empyema, results in high, irregular temperature, and is accompanied by severe general symptoms, the prostration and loss of strength being practically marked. if the pus he not evacuated by operative means, it is liable to rupture externally through the chest-wall, either into the lung or into the abdominal cavity.
Every case of pleurisy must be looked upon as a serious disease, because even the restricted and apparently harmless inflammation may grow rapidly worse if not properly attended to. As a rule, the severity of the case depends to a large extent on the underlying disease.
If a person be seized with a sudden pain in the side of the chest, has difficulty in breathing, and is oppressed by a sense of thoracic pressure, it is best to call a physician at once. If the pain be very distressing, temporary relief may be obtained by applying mustard-plaisters or warm poultices. It is not advisable to resort to measures for inducing perspiration, or to give any remedies tending to increase the amount of urine in order to hasten the absorption of the fluid in the pleural cavity ; for it is very essential that the action of the heart be carefully watched under these circumstances. Medical supervision is also necessary to determine the variety of the disease, and to detect the possible formation of pus. In the case of suppuration, the patient's life very often depends on timely operation, by which a free drainage for the pus is provided. If retraction of the chest-wall result after the inflammatory process has healed, a more or less complete expansion may often be gained by the systematic use of the respiratory exercises described under GYMNASTICS. This is apt to be less successful in those severe deformities of the chest which often result in patients treated by so-called " natural methods " (diaphoretic treatment, water-cures, etc.), which fail to provide for any evacuation of the fluid accumulated in the thoracic cavity. It is also essential that the patient take very good care of himself during the period of convalescence. His food should be ample and strengthening, and he should spend a great deal of time in the open air. If his means allow it, it is well to go for a time to some suitable resort, either in a mountain region or by the seashore.
PLICA POLONICA.—See ELF-LOCK.
PNEUMONIA.—See LUNGS, DISEASES OF.
PODOPHYLLUM.--The root of the May-apple, or Podophyllum pel lotion, a herb growing extensively in woods and plantations. It con tains a resin of somewhat variable composition, the action of which depends on the presence of the more powerful substances podophyllotoxine and picropodophylline. Podophyllnin is a slow hut reliable cathartic, which directly stimulates the intestines, and increases the flow of bile. It is usually given in combination with other drugs. An over-close irritates the bowel, and causes violent purging, blood and mucus being passed in severe cases. The dose of the resin is from one-twelfth to half a grain, according to whether a cathartic or a purgative action is desired.
POISONING.—In medical science the knowledge of poisons is known as toxicology. Accurately to define what a poison is, is no simple matter from the medical point of view. Legally it must be restricted for purposes of convenience. But, as the laws of different countries are very far from being in accord with reference to the definition of what a poison is, it would perhaps he of little moment to attempt to define it here legally.
Medically, the difference between poisons and non-poisons, as such, does not exist. Poisonous properties depend so largely upon t he factor of amount, that one must consider the word in its adjective sense alone. Many substances, when taken in small amounts, are perfectly harmless, and may even be said to be beneficial to the body ; whereas, taken in large quantities, they are counted as poisonous substances, and the line of transition between purely beneficial, indifferent, or poisonous substances is difficult to ascertain. Thus, it is well known that arsenic is a useful substance when taken in small quantities. It improves the appetite, increases the number of blood-cells, and is an indispensable remedy in certain diseased conditions ; vet excess of arsenic results in destruction and death of tissues. The same may be said of a vast of substances, and may even be extended to include the use of water.