Glycofurol

Glycofurol 75; tetraglycol; tetrahydrofurfuryl alcohol polyethylene glycol ether; α-(tetrahydrofuranyl)-ω-hydroxypoly(oxyethylene)

α-[(Tetrahydro-2-furanyl)methyl]-ω-hydroxypoly(oxy-1,2-ethanediyl) · [31692-85-0]

C5H9O(CH2)O(C2H4O)nH; n mainly 1–2 · 190.24 (n = 2)

Solvent, humectant

Typical concentrations: — · Dosage forms: Sterile (parenteral/ophthalmic)

Used mainly as a water-miscible solvent in parenteral products for intravenous or intramuscular injection, at concentrations of up to about 50% v/v. It has also been investigated as a solvent and penetration enhancer in nasal, rectal and topical formulations and in in-situ forming implants.

A clear, colourless, almost odourless liquid with a bitter taste that produces a warm sensation on the tongue. Glycofurol 75 is the grade in which most of the material has n = 1 or 2.

Density

≈ 1.07–1.09 g/cm³ at 20 °C

Solubility

miscible with water, ethanol, glycerin, propylene glycol and polyethylene glycol 400; immiscible with arachis oil and light petroleum

Viscosity

low to moderate; somewhat more viscous than water

Stable if stored under nitrogen in a well-closed container, protected from light, in a cool, dry place. As a polyether it may slowly form peroxides on exposure to air.

Incompatible with oxidising agents.

Prepared by reacting tetrahydrofurfuryl alcohol with ethylene oxide, followed by purification to remove tetrahydrofurfuryl alcohol and other impurities.

Glycofurol is irritant when used undiluted, but is tolerated in parenteral products when diluted to about 50% v/v or less. At high doses it has central nervous system depressant and diuretic effects in animals.

Observe normal precautions for the quantity handled; eye protection and gloves are recommended.

Has been used in parenteral medicines licensed in some European countries. It is not widely used in products marketed in the USA.

Polyethylene glycol; propylene glycol; tetrahydrofurfuryl alcohol.

Glycofurol is a useful co-solvent for poorly water-soluble drugs in injections, but the content of residual tetrahydrofurfuryl alcohol and peroxides should be controlled, and the product checked for precipitation of the drug on dilution with aqueous infusion fluids.