Pharmaceutical Excipient

Polyethylene Glycol

Name: Polyethylene Glycol (PEG 400 / 4000 / 6000)
Brand: Chelora Pharmachem
SKU: CAS-25322-68-3
Availability: InStock

CAS 25322-68-3 · PEG 400 / 4000 / 6000 · IP / BP / USP-NF

Three molecular-weight grades of pharmaceutical-grade macrogol — liquid PEG 400 for co-solvency and solubilisation, solid PEG 4000 & 6000 for tablet coating, ointment bases and laxative preparations. Chelora supplies every grade to IP, BP and USP-NF monograph with full batch documentation.

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IP / BP / USP-NF grades
Non-hazardous transport
Samples to bulk

MW grades

CAS number

25322-68-3

MW range

400 – 7 000

Pharmacopoeia

IP · BP · USP-NF

Transport

Non-DG

Product overview

The workhorse excipient of modern pharmacy

Polyethylene glycol (PEG), also known as macrogol, is a synthetic polyether manufactured by ring-opening polymerisation of ethylene oxide. It is one of the most widely used pharmaceutical excipients in the world, appearing in oral, topical, rectal and parenteral dosage forms across nearly every therapeutic area.

PEG's value lies in its versatility across molecular weights. Low-MW grades such as PEG 400 are clear, viscous liquids that serve as co-solvents and solubilisers for poorly water-soluble drugs, soft-gelatin capsule fills and injectable vehicles. Higher-MW grades (PEG 4000 and PEG 6000) are waxy solids used as tablet-coating plasticisers, suppository bases and binders.

All grades are freely soluble in water, non-toxic at the levels used in formulation and compatible with a wide range of excipients and APIs. PEG is listed in the FDA Inactive Ingredient Database (IID) for oral, topical and parenteral routes, and monographed in the IP, BP and USP-NF.

Clinically, PEG 3350/4000 is the active ingredient in osmotic laxatives (e.g. Miralax, Movicol) and bowel-preparation solutions, where it works by retaining water in the intestinal lumen without being systemically absorbed.

Technical specifications

IUPAC namePoly(oxyethylene) glycol / Polyethylene glycol

SynonymsPEG, Macrogol, Carbowax, Polyoxyethylene glycol

CAS number25322-68-3

Molecular formulaH(OCH₂CH₂)ₙOH or HO(C₂H₄O)ₙH

MW — PEG 400380 – 420 g/mol (avg. ~400)

MW — PEG 40003 000 – 5 000 g/mol (avg. ~4 000)

MW — PEG 60005 000 – 7 000 g/mol (avg. ~6 000)

Appearance — PEG 400Clear, colourless, viscous liquid

Appearance — PEG 4000 / 6000White to off-white waxy solid (flakes or powder)

Solubility in waterFreely soluble at all MW grades

Solubility in organicsSoluble in chloroform, ethanol; insoluble in diethyl ether, hexane

pH (5 % aq. solution)4.5 – 7.5

Hydroxyl value — PEG 400264 – 300 mg KOH/g

Hydroxyl value — PEG 400022 – 32 mg KOH/g

Hydroxyl value — PEG 600015 – 23 mg KOH/g

Purity (assay)≥ 95.0 % (ethylene oxide equivalents, IP/BP/USP-NF)

Residue on ignition≤ 0.1 %

Heavy metals (as Pb)≤ 10 ppm

Ethylene glycol & diethylene glycol≤ 0.25 % (total)

Freezing range — PEG 400053 – 57 °C

Freezing range — PEG 600055 – 62 °C

StorageCool, dry place; protect from moisture; tightly closed

TransportNot classified as dangerous goods (Non-DG)

Applications & end uses

Industries that depend on Polyethylene Glycol

Ointment & suppository base (PEG blends)

Blends of PEG 400 (liquid) with PEG 4000 or PEG 6000 (solid) form washable, water-miscible ointment and suppository bases that melt at body temperature and release the active ingredient predictably, offering a non-greasy alternative to petrolatum bases.

Tablet coating plasticiser (with HPMC)

PEG 4000 / 6000 are widely used as plasticisers in HPMC-based film coats for oral solid dosage forms. They lower the minimum film-forming temperature, improve coat flexibility and reduce cracking during high-speed coating.

Solubiliser & co-solvent for poorly soluble drugs

PEG 400 serves as a co-solvent in oral liquid and parenteral formulations, increasing the aqueous solubility of BCS Class II and IV compounds. It is also used in soft gelatin capsule fill matrices to enhance drug dissolution.

Laxative (PEG 3350 / 4000 — osmotic)

Orally administered PEG 3350 / 4000 acts as an osmotic laxative by retaining water in the intestinal lumen. It is the basis of widely prescribed bowel preparations (e.g. Miralax, Movicol) and chronic constipation treatments.

Industrial lubricant & mould release

Higher-MW PEGs function as non-toxic lubricants and mould-release agents in rubber, metal-forming and textile processing. Their water solubility simplifies cleaning compared with petroleum-based lubricants.

Cosmetic humectant & skin-feel modifier

PEG 400 and PEG 4000 feature in lotions, creams and hair-care products as humectants and viscosity modifiers, lending a smooth, non-tacky skin feel and improving spreadability of formulations.

Available grades

Three molecular-weight grades

IP / BP / USP-NF

PEG 400 (liquid)

Co-solvent, soft-gel fill, ointment base

IP / BP / USP-NF

PEG 4000 (solid flakes)

Tablet coating, suppository base, laxative

IP / BP / USP-NF

PEG 6000 (solid flakes)

Tablet coating, binding, industrial

Packaging options

Sealed and labelled to pharmacopoeia standard

225 kg drum — MS drum with HDPE lining (PEG 400 liquid)

Standard bulk liquid unit

25 kg bag — Multi-layer paper bag with PE liner (PEG 4000/6000 flakes)

Standard pharmaceutical unit

Sample — Sealed HDPE container (liquid or solid)

QC evaluation before commitment

Documentation supplied

Complete paperwork for QC and regulatory

Certificate of Analysis (COA)

Batch-specific results for assay, hydroxyl value, pH, ethylene glycol/DEG, heavy metals, LOD, ROI and freezing range.

Safety Data Sheet (SDS)

GHS-format, 16-section SDS covering handling, first aid, fire-fighting and disposal.

Specification sheet

Limit values for each test parameter aligned to IP, BP or USP-NF monograph.

Pharmacopoeia compliance statement

Confirmation of monograph compliance for each MW grade where applicable.

Frequently asked questions

Common questions about Polyethylene Glycol

What is the difference between PEG 400, PEG 4000 and PEG 6000?+

The number denotes the approximate average molecular weight. PEG 400 is a clear viscous liquid used as a co-solvent and soft-gel fill; PEG 4000 and PEG 6000 are white waxy solids (flakes) used in tablet coating, suppository bases and as binders. All three are freely water-soluble.

Does PEG have any hazardous-goods classification?+

No. Polyethylene glycol in all three MW grades is non-hazardous and not classified as dangerous goods for air, sea or road transport. Standard packaging and labelling apply. An SDS is supplied with every order.

Which pharmacopoeia standards does Chelora PEG meet?+

All three grades are manufactured to meet Indian Pharmacopoeia (IP), British Pharmacopoeia (BP) and United States Pharmacopeia – National Formulary (USP-NF) monograph specifications. Each batch ships with a COA confirming compliance.

Can PEG 400 be used as a co-solvent in parenteral formulations?+

Yes. PEG 400 is routinely used as a co-solvent in injectable formulations (typically up to ~30 % v/v) to improve the solubility of poorly water-soluble drugs. It is listed in the FDA Inactive Ingredient Database for parenteral use.

What impurity limits apply to pharmaceutical-grade PEG?+

Key limits include ethylene glycol and diethylene glycol (≤ 0.25 % total), heavy metals (≤ 10 ppm as Pb) and residue on ignition (≤ 0.1 %). The exact limits follow the IP/BP/USP-NF monograph for the relevant MW grade.

What is the typical lead time for a bulk PEG order?+

Standard lead time is 5 – 10 working days for domestic orders and 10 – 14 days for export, depending on grade and volume. We keep PEG 400 and PEG 4000 in ready stock; PEG 6000 may require additional lead time for large quantities.

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