This section is from the book "Materia Medica Pharmacy, Pharmacology And Therapeutics", by W. Hale White. Also available from Amazon: Materia Medica Pharmacy, Pharmacology And Therapeutics..
Barium Dioxide. BaO2=168.82. Synonym.- Barium Peroxide.
By conducting oxygen over Barium Oxide, heated to full redness.
A heavy, grayish-white, or pale, yellowish-white, amorphous, coarse powder, odorless and tasteless. When exposed to the air it slowly attracts moisture and Carbon Dioxide, and is gradually decomposed. Solubility. - Almost insoluble in water.
Sulphates and nitrates.
Barium Dioxide is used in preparing Aqua Hydrogenii Dioxidi.
Barium chloride (not official) causes the cardiac contractions to become slower and more forcible, acting like digitalis. The blood-vessels are constricted, and the blood pressure rises. The plain muscular fibres of the intestine may be excited, and the peristalsis is increased. In these respects it resembles ergot as well as digitalis. It acts like veratrine when applied locally to voluntary muscles, prolonging the contraction; but this effect is done away with by the application of potassium salts.
These are not often given, but the chloride (dose, 1/10 to 1/2 gr., .006 to .03 gm.) has been used for mitral insufficiency accompanied by irregularity of the heart, for haemorrhage, and as a stimulant in atony of the bladder or intestine. Formerly it was given in nervous diseases. The waters of Llangammarch wells contain 6.7 gr. .40 gm. to the Imperial gallon 4545 c.c. of barium chloride, and have been used in cardiac cases. The sulphide (not official) has been used as a depilatory.
Poisonous doses cause salivation, thirst, vomiting, purging, difficulty of breathing, a slow pulse, and, from its action on the spinal cord, paralysis of the limbs. The heart is arrested in systole.