Pharmaceutical Excipient

Lactose Monohydrate

Name: Lactose Monohydrate
Brand: Chelora Pharmachem
SKU: CAS-64044-51-5
Availability: InStock

CAS 64044-51-5 · C₁₂H₂₂O₁₁·H₂O · MW 360.31

The world's most widely used pharmaceutical excipient — from tablet compression to dry powder inhalers. Chelora supplies IP, BP and USP-NF grade lactose monohydrate with certificate of analysis and full documentation on every batch.

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

≥ 99 %

assay purity

CAS number

64044-51-5

Specific rotation

+54.4° to +55.9°

Pharmacopoeia

IP · BP · USP-NF

Transport

Non-DG

Product overview

The backbone of solid dosage formulation

Lactose monohydrate (alpha-lactose monohydrate) is a disaccharide sugar derived from whey — a by-product of the cheese-making process. It consists of one galactose and one glucose unit linked by a beta-1,4-glycosidic bond, with one molecule of water of crystallisation incorporated into the crystal lattice.

As an excipient, lactose monohydrate is prized for its excellent compressibility, low hygroscopicity, bland taste, compatibility with a wide range of APIs and well-understood regulatory profile. It has been used in tablet manufacturing for over a century and is listed in all major pharmacopoeias (IP, BP, Ph. Eur., USP-NF, JP).

Spray-dried grades (SuperTab, FlowLac types) combine crystalline lactose monohydrate with a small fraction of amorphous lactose to deliver superior flow and direct-compression performance, eliminating the need for wet granulation in many formulations and reducing manufacturing costs and cycle times.

Inhalation-grade lactose (InhaLac type) is produced with tightly controlled particle-size distribution and surface morphology to serve as the carrier particle in dry powder inhaler (DPI) formulations. The carrier ensures uniform blending, accurate dosing and effective aerosolisation of micronised API particles to the deep lung.

Technical specifications

IUPAC name4-O-beta-D-Galactopyranosyl-alpha-D-glucopyranose monohydrate

SynonymsAlpha-lactose monohydrate, Milk sugar, Lactose hydrate

CAS number64044-51-5

Molecular formulaC₁₂H₂₂O₁₁·H₂O

Molecular weight360.31 g/mol

AppearanceWhite to off-white crystalline powder

Melting point201 – 202 °C (anhydrous); monohydrate loses water ~100 °C

Solubility in waterFreely soluble (~195 g/L at 25 °C)

Purity (assay)≥ 99.0 % (IP / BP / USP-NF)

Specific rotation [α]D²⁰+54.4° to +55.9°

Loss on drying4.5 – 5.5 % (corresponds to 1 mol water)

Heavy metals (as Pb)≤ 5 ppm

pH (10 % solution)4.0 – 6.5

Sulphated ash≤ 0.1 %

Protein and light-absorbing impuritiesPasses test

Acidity / alkalinityComplies (IP / BP / USP-NF)

StorageCool, dry place; protect from moisture

TransportNot classified as dangerous goods (Non-DG)

Applications & end uses

Industries that depend on Lactose Monohydrate

Tablet filler and diluent

Lactose monohydrate is the most widely used pharmaceutical excipient by volume. It serves as the primary filler-diluent in wet granulation, dry granulation and direct compression tablet formulations, providing bulk, compressibility and content uniformity.

Dry powder inhaler (DPI) carrier

Inhalation-grade lactose with controlled particle-size distribution acts as the carrier particle in DPI formulations, ensuring uniform blending and accurate dose metering of micronised active pharmaceutical ingredients to the lung.

Capsule diluent

Lactose is used as a diluent in hard gelatin and HPMC capsule fills, enabling accurate dosing of potent, low-dose APIs by providing the required fill volume and powder flow properties.

Lyophilisation bulking agent

In freeze-dried (lyophilised) parenterals and biologics, lactose monohydrate forms an elegant cake structure, supports rapid reconstitution and provides cryoprotection for sensitive proteins and vaccines during the freeze-drying cycle.

Infant formula and food industry

Food-grade lactose monohydrate is a key ingredient in infant formula, confectionery, bakery products and flavour carriers, contributing mild sweetness, browning behaviour (Maillard reaction) and bulking properties.

Confectionery and bakery

In sugar-panning, chocolate coatings and baked goods, lactose provides texture modification, reduced sweetness relative to sucrose and controlled browning, making it a versatile ingredient in the food and confectionery sector.

Available grades

Three grades for every formulation need

≥ 99.0 %

Pharma grade (200M, fine sieved)

Wet granulation tablets, capsule fill, general pharma

≥ 99.0 %

Spray-dried grade (SuperTab / FlowLac type)

Direct compression (DC) tablets, superior flow and compressibility

≥ 99.0 %

DPI inhalation grade (InhaLac type)

Dry powder inhaler carriers, controlled particle size

Packaging options

Sealed and labelled to pharmacopoeia standard

25 kg — Double-lined paper bag / HDPE drum

Standard pharmaceutical unit

50 kg — HDPE-lined fibre drum

Bulk formulation supply

Sample — Sealed HDPE container

QC evaluation before commitment

Documentation supplied

Complete paperwork for QC and regulatory

Certificate of Analysis (COA)

Batch-specific results for assay, specific rotation, loss on drying, heavy metals, pH and microbial limits.

Safety Data Sheet (SDS)

GHS-format, 16-section SDS covering handling, first aid, exposure controls 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 and grade designation where applicable.

Frequently asked questions

Common questions about Lactose Monohydrate

What is the difference between lactose monohydrate and anhydrous lactose?+

Lactose monohydrate contains one molecule of water of crystallisation (4.5 – 5.5 % by weight), while anhydrous lactose is the dried form with < 0.5 % moisture. Monohydrate is the standard grade for wet granulation; anhydrous and spray-dried forms are preferred for direct compression of moisture-sensitive APIs.

Which pharmacopoeia grades does Chelora supply?+

We supply lactose monohydrate meeting IP, BP and USP-NF monograph specifications. Spray-dried (DC-grade) and inhalation-grade (DPI-carrier) variants are also available. Each batch is supplied with a COA confirming compliance.

Is Lactose Monohydrate classified as a hazardous material?+

No. Lactose monohydrate is not classified as dangerous goods for transport purposes and is listed as GRAS (Generally Recognised As Safe) by the FDA. Standard packaging and labelling apply.

Can I use your lactose for dry powder inhaler (DPI) formulations?+

Yes. Our inhalation-grade lactose (InhaLac type) has controlled particle-size distribution specifically designed for DPI carrier applications. A detailed PSD certificate is available alongside the standard COA.

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

Standard lead time is 5 – 10 working days for domestic orders and 10 – 14 days for export, depending on grade and volume. Spray-dried and inhalation grades may require slightly longer lead times.

Do you offer samples before bulk purchase?+

Yes. Sample quantities of all three grades are available so your QC and R&D teams can verify the material against your specification before committing to a production order.

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