Polyethylene Glycol 400 (Pharmaceutical Grade)

A clear, viscous liquid polyethylene glycol used in pharmaceutical liquid and semisolid formulations as a co-solvent, solubilizer, soft-gel capsule fill vehicle, ointment base, and humectant. The dominant liquid PEG grade in injectable, oral liquid, and soft-gel pharmaceutical formulations.

Clear, colorless to slightly yellow viscous liquid, miscible with water in all proportions, miscible with ethanol, acetone, glycols, and aromatic hydrocarbons. Hygroscopic.

We supply pharmaceutical-grade PEG 400 from manufacturers in China holding ISO, GMP, USP/EP/JP DMF, Halal, Kosher, and other certifications relevant to the product and production. Low-aldehyde and parenteral-grade variants are available on request.

Common market grades include standard pharmaceutical PEG 400 for oral and topical applications, low-aldehyde PEG 400 for parenteral and ophthalmic formulations (with tightened formaldehyde and peroxide limits), and ultra-low-impurity grades for sensitive biologic and protein formulations.

Bulk and reduced-MOQ shipments. Batch-level COA covering identification, average molecular weight, viscosity, hydroxyl value, water content, ethylene oxide, 1,4-dioxane, formaldehyde, peroxide, heavy metals, and microbiology against USP, EP, JP, and BP monographs.

PEG 400 is the most widely used liquid polyethylene glycol in pharmaceutical formulation and one of the few co-solvents acceptable for parenteral use at meaningful concentrations. It has been in pharmaceutical use since the 1940s and is supported by a deep regulatory history across oral, topical, injectable, and ophthalmic routes.

Production proceeds by base-catalyzed addition polymerization of ethylene oxide, controlled to an average degree of polymerization of approximately 8 to 9. The pharmacopoeial monograph specifies an average molecular weight of 380 to 420.

Listed in USP-NF, EP, JP, and BP monographs (as Macrogol 400 in EP/JP). FDA Inactive Ingredient Database listed for parenteral routes at up to approximately 60 percent of the formulation, the highest co-solvent acceptance level of any common parenteral excipient.

The defining functional advantages are excellent solubilization of poorly water-soluble APIs (logP up to approximately 4), broad miscibility with water and many organic solvents, low toxicity, and an established parenteral track record. Low-aldehyde and low-peroxide grades are required for protein and biologic formulations where carbonyl impurities would react with the API.

Strategic position: along with propylene glycol, ethanol, and glycerin, PEG 400 is one of the four reference co-solvents in injectable and oral liquid pharmaceutical formulation. Residual ethylene oxide, 1,4-dioxane, formaldehyde, and peroxide control define grade quality above price.

• Co-solvent in injectable pharmaceutical formulations
• Soft-gel capsule fill vehicle for poorly soluble APIs
• Solubilizer in oral liquid pharmaceutical formulations
• Vehicle in topical pharmaceutical creams, lotions, and gels
• Humectant in pharmaceutical ointments and semisolid bases
• Solvent in ophthalmic lubricant and artificial tear formulations
• Plasticizer in soft-gel shells and film coatings
• Wetting agent in poorly wettable API suspensions
• Carrier in topical pharmaceutical foam systems