(Non-official.)

(Plperazidine; Ethyleneimine; Dlethylenediamine; Dlspermine.)

Origin. - Obtained by the action of ammonia on bromide or chloride of ethylene,

Description and Properties. - It occurs as a crystalline solid, exceedingly soluble in water, the solution being practically tasteless. When exposed to the air the drug is very deliquescent, becoming completely liquefied on long exposure.

Dose. -5-15 grains (0.3-1.0 Gm.).

Piperazin, Lycetol, Lysidine, and Urotropine are closely related compounds, all introduced to dissolve uric acid in the body. Since a partial death blow has recently been administered to the "uric-acid phobia," the therapeutic facilities in this line are less sought after. What is here written of piperazin is probably true of this entire series of bodies.

Antagonists and Incompatibles. - The incompatibles are alkaloids, tannic acid, preparations of cinchona, salts of iron, alum, Donovan's solution, acetanilid, phenacetine, and sodium salicylate.

Synergists. - Lithium and its salts and the lithontriptics.

Physiological Action and Therapeutics. - The drug apparently has no effect whatever upon either the digestive, circulatory, or respiratory systems. Excessive doses, however, have affected the nervous system, producing certain untoward manifestations, such as muscular tremors, hallucinations, and clonic spasms.

The drug is non-irritating when applied to mucous membranes.

Piperazin is rapidly absorbed from the stomach, circulates in the blood unchanged, and is eliminated in the urine.

The only important action of piperazin is its property of dissolving uric acid, with which it forms a neutral and exceedingly soluble salt, piperazin urate, said to be seven times more soluble in water than lithium urate. This action is prominent in test-tubes, but it is highly doubtful if it is as serviceable in the human body.

Therapeutics. - Externally and Locally. - A solution of piperazin (1 to 2 per cent.) in a mixture of water and alcohol (1 to 4, respectively) has been applied locally to gouty joints and swellings with doubtful results.

Solutions of piperazin may be injected into the bladder in order to dissolve vesical calculi. They seem to have a slight action.

In the treatment of gout some observers have reported good results. For renal and vesical calculi of the urates it is doubtful if this drug is of much service, yet it is worthy of extended trial. It is of service in chronic cystitis and in some forms of arthritis. The pruritus of diabetes is often benefited by it.

The good results which have been reported from the use of these uric-acid solvents is largely to be attributed to the immense quantities of water with which their administration is combined.

Contraindications. - None of importance can be named.

Administration. - Piperazin is best given in aerated water, although it may be acceptably administered in distilled water and syrup, orange flower water, or other agreeable vehicle.