Last updated: April 23, 2026
Who Supplies Diphenhydramine Hydrochloride (API and Finished Dosage) Globally?
Diphenhydramine hydrochloride is widely sourced because it is a legacy antihistamine with broad generic availability. Supplier identification depends on whether you need API (active pharmaceutical ingredient) or finished dosage forms (tablets, capsules, oral solution, injection). The lists below cover major, established manufacturers and common commercial sources observed across pharmaceutical supply channels.
What Are the Main API Suppliers for Diphenhydramine Hydrochloride?
Commercial API manufacturers (diphenhydramine HCl)
These companies are frequently listed as diphenhydramine hydrochloride API or API-origin manufacturers in global procurement and regulatory ecosystems:
- Zhejiang NHU Co., Ltd. (China)
- Hubei Xingfa Chemicals Group Co., Ltd. (China)
- Bharat Serums and Vaccines Limited (India)
- Aarti Drugs Limited / Aarti Pharmalabs ecosystem (India)
- Chemwerth (India)
- TCI (Tokyo Chemical Industry) (Japan; catalog chemicals and some pharmaceutical-grade supply channels)
Typical commercial procurement note: API availability is often driven by generic-grade bulk supply and established QC documentation sets (e.g., CoA, GMP status where applicable), and by the specific salt form (diphenhydramine hydrochloride) and intended compendial standard (USP/EP) used in customer specifications.
Who Supplies Diphenhydramine HCl Finished Dosage Forms?
Generic and branded finished product makers (common global sources)
Diphenhydramine hydrochloride appears in many OTC and prescription product lines. Finished products are typically supplied by multiple generic manufacturers depending on market and pack strength:
- Teva (various generic antihistamine products)
- Mylan (now Viatris) (generic antihistamine products in multiple markets)
- Perrigo (OTC legacy antihistamines in multiple formulations)
- GSK (legacy/region-dependent lineages) where applicable in certain markets
- Hikma Pharmaceuticals (generic injectables and oral products in select markets)
Market reality: finished dosage supply is fragmented by jurisdiction, strength, route (oral vs injection), and excipient system. Procurement usually pins down by NDC/EMA product code or local registration rather than by API manufacturer.
Which Suppliers Cover Injection vs Oral Formulations?
Injection-focused supply tends to be narrower
Diphenhydramine hydrochloride injection is less uniformly available than tablets/capsules, so suppliers for injectable versions are typically fewer and more regulated by facility qualification. In practice, sourcing for injection is anchored to:
- GMP injectable manufacturing capability
- sterile processing approvals
- country-specific drug registrations
Common global injectable-capable generic suppliers include:
- Hikma Pharmaceuticals
- Teva
- Viatris
- Fresenius Kabi (injectable portfolio depends on market availability)
What Specifications Do Buyers Typically Lock for Diphenhydramine Hydrochloride?
Compendial and salt-form constraints
Most procurement teams require:
- Diphenhydramine hydrochloride identity (salt form confirmed)
- USP or EP compliance (as specified in the purchase order)
- Assay and impurities within defined limits
- Residual solvents and heavy metals per the customer method or standard
- Particle size control where relevant (especially for tablets/capsules)
Quality documentation buyers request
- GMP status for API or finished dosage
- CoA per batch (assay, impurities)
- DMF or CEP references where the supplier holds them (region-dependent)
- Stability package for finished products
How to Choose the Right Supplier Category (API vs Finished Dosage)?
| Need |
Recommended supplier route |
What to verify in sourcing |
| You manufacture tablets/capsules yourself |
API supplier |
USP/EP grade, impurity profile, GMP status, DMF/CEP availability |
| You buy product for distribution |
Finished dosage supplier |
registration (NDC/EMA), pack strength, route (oral vs injection), shelf-life, labeling |
| You need sterile injection supply |
injectable-capable finished dosage supplier |
sterile manufacturing approval, batch release documentation, lead times |
Key Takeaways
- Diphenhydramine hydrochloride is sourced through two distinct channels: API suppliers and finished dosage manufacturers; injection supply is typically narrower than oral supply.
- Common API supply is concentrated among large generic-capable chemical manufacturers in China and India, plus catalog-grade suppliers for smaller procurement volumes.
- Finished dosage supply varies by market and registration; procurement is usually anchored to local product codes and pack specs, not only API origin.
FAQs
1) Can one supplier provide both diphenhydramine HCl API and finished dosage forms?
Yes, but it is not universal. Large pharma and generic players may supply finished dosage, while chemical firms often focus on API. Many buyers split sourcing by category.
2) What grade of diphenhydramine hydrochloride is typically required for compendial products?
Buyers usually specify USP or EP compliance for the salt form diphenhydramine hydrochloride and lock impurity, assay, and residual solvent limits in the quality agreement.
3) Are injection suppliers the same as tablet suppliers?
Often not. Injection manufacturing requires sterile processing capability, so injectable sourcing typically comes from a smaller set of qualified manufacturers.
4) Is diphenhydramine hydrochloride widely available year-round?
It is broadly available due to its legacy status and generic production footprint, but lead times can still vary by route and regulatory batch release requirements.
5) How do procurement teams validate a supplier quickly?
They validate via batch CoA, GMP/DMF or CEP references where available, and compendial testing alignment (USP/EP) before scaling orders.
References
[1] USP. “Diphenhydramine Hydrochloride” (monograph and related standards). United States Pharmacopeia.
[2] EMA. European Medicines Agency product information and public assessment materials for relevant antihistamine products containing diphenhydramine hydrochloride. European Medicines Agency.
[3] FDA. Orange Book and FDA drug approvals referencing diphenhydramine hydrochloride products by active ingredient and application. U.S. Food and Drug Administration.
[4] WHO. WHO Prequalification Programme and related documentation where diphenhydramine hydrochloride products or manufacturing sites appear. World Health Organization.
