Description

Diphenhydramine is a first-generation ethanolamine-class antihistamine with pronounced sedative and anticholinergic properties. This versatile active pharmaceutical ingredient (API) is critical for formulators requiring reliable and consistent pharmacological effects. It is primarily utilized by pharmaceutical manufacturers in the production of over-the-counter (OTC) sleep aids, allergy medications, antiemetics, and topical antipruritic formulations.

Application

• Pharmaceutical API: Core ingredient in OTC sleep aid tablets, capsules, and liquid formulations.
• Allergy & Cold Remedies: Key component in antihistamine preparations for relieving symptoms of allergies, hay fever, and the common cold.
• Antiemetic Formulations: Used in medications to prevent and treat nausea, vomiting, and vertigo, including motion sickness.
• Topical Preparations: Incorporated into creams, gels, and sprays to relieve itching and minor skin irritations.
• Veterinary Pharmaceuticals: Employed in veterinary medicine for its sedative and anti-allergic effects in animals.
• Drug Intermediate: Serves as a chemical precursor in the synthesis of more complex pharmaceutical compounds.

Basic Information

Product Name	Diphenhydramine
CAS No.	58-73-1
Molecular Formula	C17H21NO
Molecular Weight	255.36 g/mol
Synonyms	2-(Diphenylmethoxy)-N,N-dimethylethylamine; Benadryl (trade name); Dimedrol; Diphenhydramine Hydrochloride (salt form); DPH; β-Dimethylaminoethyl benzhydryl ether; Allergina; Wehdryl
EINECS	200-396-7

Quality Control

Our Diphenhydramine is manufactured under strict quality management systems. We provide material that meets or exceeds relevant pharmacopeial standards, including USP-NF and EP monographs. Every batch undergoes comprehensive analytical testing for identity, purity, and impurities. A Certificate of Analysis (COA) detailing all test results is provided with each shipment to ensure full traceability and compliance.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at a controlled room temperature (15-25°C). This product is hygroscopic (moisture-sensitive); the container must be kept tightly sealed to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms
Identification (HPLC)	Conforms to reference standard
Assay (HPLC)	98.0% - 102.0% (on anhydrous basis)
Water (KF)	≤ 0.5%
Residue on Ignition	≤ 0.1%
Heavy Metals	≤ 20 ppm
Related Substances (HPLC)	Individual impurity ≤ 0.5%, Total impurities ≤ 1.5%

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.