List of Excipients in Branded Drug DEMEROL

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Hospira Inc	DEMEROL	meperidine hydrochloride	0409-1176	HYDROCHLORIC ACID
Hospira Inc	DEMEROL	meperidine hydrochloride	0409-1176	SODIUM CHLORIDE
Hospira Inc	DEMEROL	meperidine hydrochloride	0409-1176	SODIUM HYDROXIDE
Hospira Inc	DEMEROL	meperidine hydrochloride	0409-1181	HYDROCHLORIC ACID
Hospira Inc	DEMEROL	meperidine hydrochloride	0409-1181	METACRESOL

DEMEROL Excipient Strategy and Commercial Opportunities for Meperidine Pharmaceutical Products

Last updated: September 24, 2026

DEMEROL is the branded form of meperidine hydrochloride, an opioid analgesic with declining clinical use because of neurotoxic metabolite accumulation, seizure risk, drug-interaction concerns, and the availability of safer alternatives. The strongest commercial opportunities are not broad analgesic expansion or premium oral reformulation. They are targeted injectable presentations, preservative-free products, institutional supply reliability, differentiated packaging, and lifecycle products that reduce dosing errors and administration burden.

The commercial case is constrained by opioid stewardship, controlled-substance regulation, generic competition, limited guideline support, and the low strategic priority of meperidine in many hospital formularies.

What is DEMEROL and how is meperidine used?

DEMEROL contains meperidine hydrochloride, a synthetic opioid agonist used for short-term treatment of moderate-to-severe pain. It has also been used for shivering and, historically, for obstetric and perioperative analgesia. Current clinical guidance generally limits its use because normeperidine, its active metabolite, can accumulate in renal impairment and produce central nervous system toxicity, including seizures.

Attribute	DEMEROL / meperidine
Active ingredient	Meperidine hydrochloride
Drug class	Opioid analgesic
Main dosage forms	Injection, historically tablets and oral solution
Primary institutional use	Short-term parenteral analgesia in selected cases
Key metabolite	Normeperidine
Major safety concerns	Respiratory depression, dependence, serotonin syndrome, seizures
Regulatory category	U.S. controlled substance, Schedule II
Main competitors	Morphine, hydromorphone, fentanyl, oxycodone and other opioid products
Commercial position	Mature, largely generic, declining strategic importance

The U.S. prescribing information warns against use in patients with significant renal impairment and against prolonged administration. The label also identifies risks from benzodiazepines, serotonergic drugs, monoamine oxidase inhibitors and other central nervous system depressants (DailyMed, 2024a).

What excipients are used in DEMEROL formulations?

The excipient strategy depends on whether the product is an injectable, tablet or oral liquid. The injectable presentation has the clearest commercial relevance because parenteral meperidine remains the principal hospital dosage form.

Injectable formulation

Public U.S. labeling for meperidine hydrochloride injection identifies water for injection as the principal vehicle. The pH may be adjusted with hydrochloric acid or sodium hydroxide. Some presentations or manufacturers may use additional excipients, including preservatives, depending on concentration, container closure and intended use.

A commercial developer must distinguish among:

1. Preservative-free single-dose ampoules or vials.
2. Preserved multidose containers.
3. Ready-to-administer prefilled syringes.
4. Pharmacy bulk packages.
5. Concentrated and dilute presentations.

The choice affects container compatibility, microbial-control requirements, stability, hospital handling and regulatory classification.

Oral tablets

Historical meperidine tablets used conventional solid-dose excipients such as diluents, binders, disintegrants, lubricants and colorants. The commercial opportunity for a new tablet is limited because the dosage form is technically straightforward and meperidine tablets have lost market relevance in the United States.

Potential excipient functions include:

Function	Candidate excipient classes	Commercial purpose
Dilution	Lactose, microcrystalline cellulose, dibasic calcium phosphate	Tablet mass and content uniformity
Binding	Povidone, pregelatinized starch, hydroxypropyl cellulose	Mechanical strength
Disintegration	Crospovidone, croscarmellose sodium, sodium starch glycolate	Rapid release
Lubrication	Magnesium stearate, sodium stearyl fumarate	Manufacturing efficiency
Taste control	Film coating, polymeric coating	Improved acceptability
Identification	Colorants, imprinting	Medication-error reduction

A tablet reformulation would need a clear advantage because generic substitution and limited clinical demand would make premium pricing difficult.

Oral liquid

An oral solution or concentrate could use purified water, pH modifiers, sweeteners, preservatives and flavoring agents. The principal development risks are dose-measurement error, accidental exposure, microbial stability, palatability and controlled-substance diversion.

An oral liquid could have limited value in specialist settings but would face substantial risk under opioid-safety policies. A lower-concentration, unit-dose presentation may reduce administration errors, but it could also increase volume and handling burden.

What excipient strategy is strongest for DEMEROL injection?

The strongest strategy is a preservative-free, ready-to-administer injectable product with a narrow excipient profile and strong container-closure controls.

Preservative-free positioning

Preservative-free meperidine injection could target:

• Neonatal and pediatric environments where preservative exposure is restricted.
• Operating rooms and procedural areas.
• Emergency departments.
• Hospitals seeking single-dose presentations.
• Automated dispensing systems that favor standardized unit doses.

The benefit is operational rather than therapeutic. Removing preservatives does not eliminate meperidine’s opioid risks, but it can support use in settings where benzyl alcohol or other antimicrobial preservatives are undesirable.

A developer must demonstrate sterility assurance through container design, validated aseptic processing or terminal sterilization where compatible with the formulation and package.

Ready-to-administer syringes

Prefilled syringes could create more defensible commercial differentiation than a conventional vial. Potential benefits include:

• Reduced pharmacy compounding.
• Lower preparation time.
• Lower calculation and withdrawal error.
• Better barcode integration.
• More consistent dose presentation.
• Reduced manipulation of a controlled substance.

The principal barriers are syringe adsorption, extractables and leachables, plunger compatibility, needle configuration, drug stability and controlled-substance reconciliation. A prefilled product also requires a reliable tamper-evident design and a secure supply chain.

Low-volume presentations

Meperidine injection is available in multiple strengths in the U.S. market. A portfolio with clearly differentiated concentrations could address specific institutional workflows, but excessive concentration options increase selection risk.

A commercially disciplined portfolio would prioritize:

• One standard adult concentration.
• One lower-concentration option for dose titration.
• A unit-dose package for emergency and perioperative use.
• Clear labeling designed to reduce confusion between milligrams per milliliter and total syringe content.

What formulation patents could protect a new DEMEROL product?

A conventional meperidine injection is unlikely to support a strong composition-of-matter patent because the active ingredient is old and widely disclosed. Protection would need to come from formulation, device, manufacturing or use claims.

Potential patentable areas include:

Patent area	Potential claim subject	Relative strength
Ready-to-administer syringe	Stable meperidine formulation in a specific syringe system	Moderate
Container closure	Reduced adsorption or leachables profile	Moderate
Stability	Defined pH, concentration and storage conditions	Low to moderate
Manufacturing	Aseptic process or terminal sterilization method	Low to moderate
Device integration	Barcode, tamper evidence or dose-control architecture	Moderate
Combination product	Syringe or injector with administration controls	Moderate
Method of use	Restricted short-term use in a defined population	Low
Excipient composition	Specific preservative-free or buffering system	Low unless unexpected results are demonstrated

Patent strength would depend on demonstrated technical effect. For example, a patent claiming a particular pH range would be weak if the range merely reflects routine optimization. A stronger filing would link the range to an unexpected result such as reduced degradation, lower adsorption, improved syringe stability or extended refrigerated shelf life.

How does DEMEROL compare with competing opioid injection products?

Meperidine competes against products with stronger guideline support and larger hospital demand.

Product	Principal strength	Excipient opportunity	Commercial assessment
Meperidine injection	Established supply and legacy use	Preservative-free, prefilled syringe, error-resistant packaging	Niche and declining
Morphine injection	Broad clinical use and multiple concentrations	Ready-to-administer and premix systems	Larger market, higher competition
Hydromorphone injection	High potency and hospital use	Low-volume syringe and safety labeling	Stronger premium potential
Fentanyl injection	Rapid onset and perioperative use	Stable prefilled and anesthetic workflow formats	Strong institutional demand
Ketorolac injection	Nonopioid alternative for selected pain	Ready-to-use packaging	Substitution risk for meperidine
Oxycodone injection	Limited parenteral role	Specialty formulations	Smaller direct overlap

Meperidine’s excipient strategy must therefore solve an operational problem. A formulation that only matches an existing vial will have limited negotiating power with hospital systems.

When does DEMEROL lose exclusivity?

DEMEROL has no meaningful U.S. new-molecule exclusivity remaining. Meperidine hydrochloride is an old active ingredient, and generic injectable products have been marketed for many years.

The relevant exclusivity questions are therefore:

• Whether a specific branded product remains actively marketed.
• Whether an individual formulation has an unexpired patent.
• Whether an ANDA applicant has filed a Paragraph IV certification.
• Whether a product is listed in the Orange Book.
• Whether supply disruption or manufacturing constraints create temporary commercial advantage.

For an old injectable, market exclusivity is more likely to arise from regulatory approval, reliable manufacturing, shortage status or hospital contracting than from long-lived patent protection.

What is the Orange Book status of DEMEROL?

The Orange Book identifies approved drug products and patent or exclusivity information for listed reference products. A branded or reference-listed DEMEROL product must be checked against the current FDA database because listing status, marketing status and active product codes can change over time (FDA, 2024a).

For commercial diligence, the relevant fields are:

Orange Book issue	Why it matters
Reference-listed drug status	Determines the ANDA reference pathway
Active ingredient and strength	Defines the scope of generic equivalence
Dosage form	Separates injection, tablet and oral products
Patent listings	Determines possible Paragraph IV exposure
Exclusivity codes	Identifies remaining regulatory barriers
Marketing status	Distinguishes active, discontinued and withdrawn products

A company should not assume that a legacy brand name guarantees an active reference product or an enforceable patent estate.

Which companies are challenging DEMEROL?

The market is primarily exposed to generic competition rather than a single high-profile challenger. Meperidine hydrochloride injection has historically been marketed by multiple generic manufacturers and contract suppliers. The competitive field can include major injectable manufacturers, specialty pharmaceutical companies and authorized distributors.

Relevant competitive factors include:

• FDA approval status by strength.
• Current commercial availability.
• Drug-shortage history.
• Manufacturing-site reliability.
• Hospital group purchasing contracts.
• Controlled-substance distribution controls.
• Ability to supply prefilled syringes.
• Packaging and barcode compliance.

Paragraph IV litigation is less likely to be commercially central than abbreviated approvals and supply competition because the active ingredient and basic dosage forms are old. A new formulation with an unexpired patent could create litigation risk, but a standard meperidine injection would generally face limited patent barriers.

What generic entry risks exist for a new DEMEROL formulation?

A reformulated meperidine product would face five principal generic-entry risks.

Formulation copying

If the product is protected only by a narrow excipient combination, a competitor may design around the claim using a different buffer, preservative system or container.

ANDA substitution

If the product is therapeutically equivalent to an approved reference product, an ANDA applicant may compete on price without reproducing every commercial element of the branded presentation.

Weak method-of-use claims

Claims directed to short-term pain management or perioperative use may be vulnerable because the underlying uses are old and broadly described in clinical literature.

Limited switching costs

Hospitals can often switch between opioid injectables when formulary committees approve alternatives. A packaging advantage must be material enough to justify a premium.

Small market size

A narrow market reduces the economic value of expensive patent litigation. Generic entrants may accept lower margins if they can secure institutional contracts.

What manufacturing and intellectual-property barriers affect DEMEROL?

Manufacturing barriers are more important than active-ingredient patents.

Key barriers include:

• Sterile manufacturing capacity.
• Validated aseptic filling.
• Controlled-substance security.
• Schedule II recordkeeping.
• Reliable supply of glass vials, elastomeric closures and prefilled syringes.
• Container-closure integrity.
• Extractables and leachables testing.
• Stability data across storage conditions.
• Serialization and barcode implementation.
• Qualification of backup manufacturing sites.

For a prefilled syringe, the device component may create stronger differentiation than the excipient itself. A company could combine formulation claims with claims covering syringe materials, dose markings, tamper evidence and automated dispensing compatibility.

What licensing deals could create commercial value?

A licensing strategy would be more attractive for a company with sterile injectable capacity, hospital distribution and controlled-substance infrastructure.

Potential deal structures include:

1. Licensing a ready-to-administer syringe technology to an established generic injectable manufacturer.
2. Supplying a proprietary container-closure system to a hospital-focused pharmaceutical company.
3. Co-developing preservative-free presentations with a contract development and manufacturing organization.
4. Acquiring a discontinued or under-marketed reference product to support a reformulation.
5. Licensing hospital automation, barcode or medication-safety technology.

A royalty-only deal would be difficult to justify without a differentiated formulation or device patent. A supply agreement with minimum purchase commitments may be more practical than a broad territorial license.

What FDA regulatory pathway applies to a new DEMEROL product?

A standard generic meperidine injection would typically use the ANDA pathway if the product can demonstrate pharmaceutical equivalence and bioequivalence to an appropriate reference product. A materially different formulation, delivery device or route may require a 505(b)(2) application rather than an ANDA.

The regulatory pathway depends on:

• Dosage form.
• Active ingredient concentration.
• Route of administration.
• Excipients.
• Preservative status.
• Container closure.
• Device integration.
• Reference product availability.
• Need for clinical or human-factor data.

FDA guidance for generic injectables emphasizes equivalence, product quality, sterility and injectable-specific chemistry, manufacturing and controls requirements (FDA, 2023). A prefilled syringe may trigger combination-product and device-review considerations.

How strong is the DEMEROL patent estate?

The underlying patent estate is weak because meperidine is an old active ingredient with broad generic availability. A new commercial program could still establish a moderate formulation or device estate if it produces measurable technical advantages.

Estate component	Estimated strategic value
Meperidine compound patents	None of practical relevance
Standard injection formulation	Weak
Preservative-free formulation	Low to moderate
Prefilled syringe	Moderate
Container-closure system	Moderate
Manufacturing process	Low to moderate
Method-of-use patents	Weak
Hospital workflow and packaging IP	Moderate
Trademark and brand assets	Limited without active demand

The strongest defensibility would come from a product system rather than a single excipient claim.

What are the most attractive commercial opportunities?

The best opportunities are concentrated in institutional markets.

Opportunity 1: Preservative-free unit-dose injection

This product could target hospitals, pediatric settings and procedural areas. The opportunity depends on demonstrating a real handling or patient-population advantage.

Opportunity 2: Ready-to-administer syringe

The value proposition is lower preparation burden and improved medication safety. This format could command a premium if supported by hospital workflow data.

Opportunity 3: Supply-reliable niche product

Manufacturing reliability can create commercial value during shortages or supply interruptions. This is a procurement opportunity rather than a patent-led opportunity.

Opportunity 4: International markets

Meperidine remains available in some markets where analgesic access, legacy protocols and local manufacturing conditions differ from the United States. Geographic expansion requires country-specific narcotics controls, pharmacovigilance, labeling and registration analysis.

Opportunity 5: Controlled-substance packaging technology

Tamper-evident packaging, unit-dose reconciliation and electronic inventory integration may have greater value than new excipients. The technology could also apply to morphine, hydromorphone and fentanyl products.

Key Takeaways

• DEMEROL is meperidine hydrochloride, an old opioid with declining clinical use.
• The commercial opportunity is concentrated in injectable products, not conventional oral reformulation.
• Preservative-free vials, unit-dose packaging and ready-to-administer syringes offer the clearest differentiation.
• A standard meperidine injection has limited patent strength and substantial generic-entry exposure.
• Formulation patents must show an unexpected technical effect, not routine excipient optimization.
• Manufacturing, controlled-substance compliance, sterile capacity and hospital contracting are major barriers.
• FDA pathway selection depends on whether the product is a conventional generic, a reformulated injection or a device-integrated product.
• The strongest product strategy combines formulation, container-closure, packaging and workflow IP.

FAQs About DEMEROL Excipients and Commercial Strategy

Can a preservative-free DEMEROL injection obtain patent protection?

Yes, but a preservative-free claim alone may be weak. Protection would be stronger if the formulation also demonstrates improved stability, reduced adsorption, better container compatibility or a defined patient-population benefit.

Is DEMEROL still commercially attractive in the United States?

Only as a focused institutional product. Broad growth is limited by opioid stewardship, safety concerns, generic competition and substitution by morphine, hydromorphone and fentanyl.

Could a DEMEROL prefilled syringe qualify for 505(b)(2) approval?

It could, depending on the reference product, formulation differences, device characteristics and data requirements. A conventional equivalent injection may be more suitable for an ANDA.

Are meperidine method-of-use patents commercially strong?

Generally, no. Broad analgesic-use claims are vulnerable because meperidine’s clinical uses are longstanding. Narrow claims tied to a specific dosing protocol or patient subgroup would require strong clinical support.

What is the best licensing partner for a new DEMEROL formulation?

The strongest partner would have sterile injectable manufacturing, Schedule II distribution controls, hospital contracting access and experience with prefilled syringes or unit-dose packaging.

References

1. DailyMed. (2024a). DEMEROL- meperidine hydrochloride injection, solution. U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/

2. U.S. Food and Drug Administration. (2023). Product-specific guidance for meperidine hydrochloride injection. FDA. https://www.fda.gov/

3. U.S. Food and Drug Administration. (2024a). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book

4. U.S. Food and Drug Administration. (2024b). Drug shortages database. FDA. https://www.accessdata.fda.gov/scripts/drugshortages/

5. U.S. Food and Drug Administration. (2024c). Meperidine hydrochloride injection prescribing information. FDA and DailyMed labeling database. https://dailymed.nlm.nih.gov/