List of Excipients in Branded Drug HYDROCODONE POLISTIREX AND CHLORPHENIRAMINE POLISTIREX

Generic Drugs Containing HYDROCODONE POLISTIREX AND CHLORPHENIRAMINE POLISTIREX

Company	Ingredient	NDC	Excipient
ATLANTIC BIOLOGICALS CORP	hydrocodone polistirex and chlorpheniramine polistirex	17856-0087	ASCORBIC ACID
ATLANTIC BIOLOGICALS CORP	hydrocodone polistirex and chlorpheniramine polistirex	17856-0087	D&C YELLOW NO. 10
ATLANTIC BIOLOGICALS CORP	hydrocodone polistirex and chlorpheniramine polistirex	17856-0087	HIGH FRUCTOSE CORN SYRUP

What are the Most Frequently-Used Excipients in HYDROCODONE POLISTIREX AND CHLORPHENIRAMINE POLISTIREX?

# Of NDCs	Excipient
8	ASCORBIC ACID
2	CORN OIL
8	D&C YELLOW NO. 10

Excipient Strategy and Commercial Opportunities for Hydrocodone Polistirex and Chlorpheniramine Polistirex

Last updated: August 12, 2026

Hydrocodone polistirex and chlorpheniramine polistirex are the active drug-resin complexes in Tussionex Pennkinetic Extended-Release Oral Suspension, a prescription antitussive and antihistamine product. The commercial opportunity is primarily in generic or authorized-generic development, improved suspension engineering, tamper-resistant delivery, pediatric acceptability, and manufacturing cost reduction.

The core formulation challenge is to maintain dose uniformity and controlled release while preventing resin separation, sedimentation, crystal growth, taste release, and inaccurate dosing. Because hydrocodone is an opioid, any product strategy must also address controlled-substance compliance, diversion risk, abuse-deterrence expectations, and restrictions on pediatric cough-and-cold use.

What is hydrocodone polistirex and chlorpheniramine polistirex?

Hydrocodone polistirex is a hydrocodone-ion-exchange resin complex. Chlorpheniramine polistirex is the corresponding extended-release complex of chlorpheniramine. The resin complexes are dispersed in an oral suspension rather than dissolved as free drug.

The reference product, Tussionex, contains the following labeled strength per 5 mL:

Component	Labeled amount per 5 mL	Function
Hydrocodone polistirex	Equivalent to 10 mg hydrocodone	Opioid antitussive
Chlorpheniramine polistirex	Equivalent to 8 mg chlorpheniramine	Long-acting antihistamine
Polistirex resin complexes	Quantity sufficient to deliver the labeled dose	Ion-exchange controlled-release matrix

Tussionex is indicated for temporary relief of cough and upper-respiratory symptoms associated with allergy or the common cold. The FDA label identifies the product as an extended-release suspension and requires shaking before use because the drug-resin particles are dispersed in a liquid vehicle (U.S. Food and Drug Administration [FDA], 2023).

What excipients are used in the reference hydrocodone-chlorpheniramine suspension?

The reference formulation uses a multi-function excipient system. The labeled inactive ingredients include carrageenan, FD&C Yellow No. 6, flavor, high-fructose corn syrup, methylparaben, polyethylene glycol 3350, polysorbate 80, povidone, propylene glycol, purified water, sucrose, and xanthan gum (FDA, 2023).

Excipient	Likely formulation role	Commercial relevance
Carrageenan	Suspending and rheology-control agent	Helps maintain particle dispersion
Xanthan gum	Viscosity modifier and suspending polymer	Reduces sedimentation and supports dose uniformity
Povidone	Wetting, dispersing, or viscosity-supporting polymer	May improve particle incorporation
Polysorbate 80	Surfactant and wetting agent	Supports uniform dispersion of hydrophobic resin particles
Polyethylene glycol 3350	Solubilizer, humectant, and vehicle modifier	Can affect mouthfeel and viscosity
Propylene glycol	Cosolvent and humectant	Supports flavor and preservative systems
Sucrose and high-fructose corn syrup	Sweeteners and vehicle solids	Mask resin and drug-associated taste
Methylparaben	Preservative	Controls microbial growth in the aqueous suspension
Flavor	Palatability system	Important for adherence and repeat use
FD&C Yellow No. 6	Colorant	Product identification and consumer acceptability
Purified water	Continuous phase	Primary suspension vehicle

The strategic importance of the excipient system is greater than the individual ingredients. A generic applicant must reproduce the product's physical behavior, including sedimentation rate, redispersibility, viscosity, particle-size distribution, syringe or spoon delivery, and drug release.

How does the polistirex resin control drug release?

Polistirex complexes use an ion-exchange mechanism. Drug molecules are associated with a cross-linked sulfonated polymer resin. In the gastrointestinal tract, ionic exchange with endogenous ions gradually releases the active ingredient.

Release depends on several variables:

• Resin cross-link density
• Drug loading
• Particle-size distribution
• Degree of drug-resin complexation
• pH and ionic strength
• Competing ions in gastrointestinal fluid
• Polymer swelling
• Suspension-processing conditions
• Coating or surface modification, if used

The excipient vehicle does not independently create the extended-release profile. It must preserve the physical integrity and dispersion of the resin particles. Excessive surfactant, unsuitable pH, high ionic strength, or aggressive wet processing can change surface exchange behavior and produce faster or less consistent release.

For a generic product, the key technical target is not simply chemical equivalence. The formulation must achieve comparable in vitro release, dose uniformity, particle distribution, and pharmacokinetic performance under the applicable FDA pathway.

What excipient strategy is most suitable for a generic product?

A conservative formulation strategy would preserve the reference product's broad excipient architecture while optimizing the components that create the greatest development risk.

Suspension stability

Carrageenan and xanthan gum provide complementary rheology. Xanthan gum delivers high low-shear viscosity and shear-thinning behavior. Carrageenan can improve suspension structure and particle immobilization. The combination can reduce sedimentation while allowing the product to flow after shaking.

The target is a suspension that:

1. Does not form a hard cake during storage.
2. Redisperses rapidly with ordinary shaking.
3. Delivers a reproducible dose through a calibrated oral syringe.
4. Does not become excessively viscous at refrigerated or room temperatures.
5. Maintains consistent viscosity after repeated opening and dosing.

A high-viscosity product may improve physical stability but can create dose-delivery problems, air entrapment, and poor patient acceptance. A low-viscosity product can sediment rapidly and increase dose variability.

Wetting and dispersion

Polysorbate 80, povidone, and polyethylene glycol 3350 can support wetting of the resin complex. Their concentrations require careful optimization. Over-wetting may increase aggregation or alter the particle surface. Excess surfactant can also create foaming, flavor instability, and packaging interaction.

The preferred process is typically a controlled pre-dispersion of the resin complex followed by gradual incorporation into the structured vehicle. High-shear processing should be evaluated because it can modify agglomerate size and change the apparent release profile.

Taste masking

The resin complex may reduce immediate release of hydrocodone and chlorpheniramine in the mouth, but it does not eliminate taste risk. Bitterness can arise from unbound drug, surface-associated drug, flavor components, or polymer interactions.

The reference product uses a high-sugar system, flavor, and viscous vehicle. A commercial developer could pursue:

• Optimized flavor systems
• Reduced free-drug fraction
• Alternative sweetener combinations
• Resin particle surface treatment
• Microencapsulation
• Higher-viscosity oral suspension technology
• Sugar-reduced or sugar-free vehicles

Sugar-free development is commercially attractive for patients with diabetes and for broader formulation differentiation. It introduces new risks, including polyol-related gastrointestinal effects, altered viscosity, preservative compatibility, and different sensory behavior.

Microbial preservation

The aqueous formulation requires microbial control. Methylparaben is used in the reference formulation, but a generic developer could evaluate alternative systems such as propylparaben combinations, benzoate systems, or other permitted preservatives.

Preservative selection must account for:

• Vehicle pH
• Partitioning into the resin or flavor phase
• Container compatibility
• Preservative efficacy testing
• Repeated-use contamination
• Pediatric exposure limits
• Stability during in-use storage

The preservative system may become an important regulatory differentiator if the product is reformulated for a specific patient population.

What formulations are protected by the reference product's intellectual property?

The principal technical protection historically associated with Tussionex-type products has centered on the drug-resin complex and extended-release suspension technology rather than on ordinary excipients such as sucrose, water, xanthan gum, or methylparaben.

Potentially relevant claim categories include:

Claim category	Typical scope	Generic-development impact
Drug-resin complex	Hydrocodone or chlorpheniramine associated with polistirex	May require a non-infringing complex or licensed technology
Controlled-release oral suspension	Release profile and dosage form	Can affect formulation design and bioequivalence strategy
Particle engineering	Resin particle size, coating, or surface treatment	May create process and characterization barriers
Suspension vehicle	Specific polymer, surfactant, sweetener, or pH combination	Usually easier to design around than the active complex
Dosing system	Calibrated oral dosing device or delivery configuration	May create device-related constraints
Method of use	Relief of cough, cold, or allergy symptoms	Scope may be limited by regulatory and labeling requirements

Because Tussionex is an older product, historical patent terms are unlikely to create the same barrier as a recently approved extended-release opioid product. The practical freedom-to-operate question is whether any unexpired claims cover a specific resin complex, manufacturing process, formulation combination, or delivery device. The FDA Orange Book should be reviewed for current listed patents and exclusivity status before a filing or launch decision (FDA, 2024a).

What is the FDA regulatory status and Orange Book position?

Tussionex is an FDA-approved prescription oral suspension containing hydrocodone polistirex and chlorpheniramine polistirex. It is regulated as a combination drug product with an opioid active ingredient. FDA labeling includes boxed-warning language and opioid-related prescribing restrictions (FDA, 2023).

The likely regulatory route for a competing product is an abbreviated new drug application under section 505(j) of the Federal Food, Drug, and Cosmetic Act. The applicant would generally need to establish pharmaceutical equivalence and bioequivalence to the reference listed drug.

Key regulatory issues include:

• Same active ingredients and strengths
• Same dosage form and route of administration
• Comparable extended-release performance
• Dose uniformity after shaking
• Comparable pharmacokinetic exposure
• Container-closure suitability
• Preservative efficacy
• Opioid labeling and risk controls
• Controlled-substance registration and distribution compliance

There is no biosimilar pathway for this product. Hydrocodone polistirex and chlorpheniramine polistirex are small-molecule drug-resin complexes, not biologics. Biosimilar risk is therefore irrelevant; generic substitution and 505(j) litigation are the relevant competitive mechanisms.

When does hydrocodone polistirex and chlorpheniramine polistirex lose exclusivity?

The active ingredients are associated with an older prescription product, and the core commercial opportunity is post-exclusivity generic competition rather than new-molecule exclusivity.

Exclusivity analysis should separate four concepts:

Exclusivity type	Relevance to Tussionex-type product
New chemical entity exclusivity	Not expected to be commercially relevant for this legacy combination
Three-year clinical-investigation exclusivity	Generally tied to a qualifying new approval or supplement
Pediatric exclusivity	Could extend listed patent terms if granted, but must be checked in the Orange Book
Patent exclusivity	Depends on any unexpired formulation, process, or device claims

A historical approval date alone does not establish current market freedom. Patent expiration depends on the specific patent family, terminal disclaimers, PTA, PTE, continuations, and claim scope. A current Orange Book and USPTO review is required for a launch-date determination (FDA, 2024a; U.S. Patent and Trademark Office [USPTO], 2024).

Which companies are challenging the reference product?

The relevant challengers are generic drug manufacturers capable of developing controlled-release oral suspensions and managing Schedule II opioid compliance. Potential participants include large generic companies, specialty pharmaceutical manufacturers, and contract-development organizations.

A challenger would likely select one of three strategies:

1. File a conventional ANDA against the reference listed drug.
2. Develop an authorized generic or licensed product through the brand owner.
3. Launch a differentiated reformulation under a separate NDA if ANDA equivalence is technically difficult.

Paragraph IV litigation is possible if the reference product has listed patents. A first applicant with a valid Paragraph IV certification may seek 180-day generic exclusivity, subject to statutory forfeiture and other first-filer rules. The commercial value of first-filer status would depend on the size of the remaining market, the number of competing applicants, and the probability that litigation delays entry.

What generic entry risks exist for hydrocodone-chlorpheniramine suspension?

The main risks are technical and commercial rather than chemical.

Bioequivalence risk

Extended-release resin complexes can produce complex pharmacokinetics. Small changes in resin loading, particle size, vehicle composition, or release media can affect peak concentration and exposure.

A formulation may pass simple assay and dissolution testing yet fail in vivo bioequivalence. The developer should expect close control of:

• Hydrocodone and chlorpheniramine exposure
• Maximum concentration
• Time to maximum concentration
• Food effects
• Intra-subject variability
• Alcohol interaction or dose-dumping behavior

Dose-uniformity risk

Suspension products are vulnerable to stratification. The first and last doses in a bottle may differ if the product settles or forms a compact sediment. This is especially important for hydrocodone because a concentrated dose can create a safety event.

Abuse and diversion risk

Hydrocodone is a Schedule II controlled substance in the United States. The resin complex may limit immediate release, but it should not be treated as complete abuse deterrence. A developer should evaluate manipulation, extraction, crushing, chewing, and co-administration with alcohol or other solvents.

An abuse-deterrent formulation could create differentiation, but it would require a separate development and regulatory strategy. A standard ANDA cannot assume that a novel abuse-deterrent claim will be accepted without supporting evidence and labeling alignment.

Pediatric and caregiver-use risk

The product's oral-liquid presentation supports use by children and adults but also creates dosing risks. FDA has advised against use of prescription opioid cough-and-cold medicines containing hydrocodone in children younger than 18 years because the risks outweigh the benefits (FDA, 2018).

Commercial development should therefore emphasize calibrated dosing, clear labeling, child-resistant packaging, and adult-use positioning. A redesigned dosing syringe could improve usability but might trigger device and combination-product review considerations.

How strong is the patent estate for this product?

The patent estate is likely weaker than the regulatory and manufacturing barriers.

A strong commercial position would require enforceable claims covering one or more of the following:

• The specific hydrocodone-polisti​​rex complex
• The specific chlorpheniramine-polisti​​rex complex
• A narrow extended-release profile
• A distinctive particle-size distribution
• A manufacturing process that is difficult to replicate
• A formulation that prevents dose dumping
• A protected dosing device

Ordinary excipients are generally weak standalone barriers because competitors can substitute polymers, sweeteners, preservatives, surfactants, and flavors. The strongest practical barrier may be know-how involving resin loading, particle processing, suspension order of addition, and scale-up.

A patent search should distinguish expired composition patents from potentially active continuation or process patents. Patent families should be assessed in the United States, Canada, Europe, Japan, and other high-value markets. Patent protection is unlikely to be globally uniform because product approvals, Orange Book listing, and generic litigation operate differently by jurisdiction.

What commercial opportunities exist beyond a standard generic?

Authorized generic

An authorized generic could preserve brand-channel economics while offering lower-cost distribution. This approach may be attractive if the brand owner wants to manage erosion or capture institutional and payer volume.

Sugar-free reformulation

A sugar-free suspension could address diabetes-conscious consumers and institutional formularies. The opportunity depends on proving equivalent release and maintaining acceptable taste and viscosity.

Improved dosing presentation

A bottle-and-syringe package with a calibrated oral syringe, stronger resuspendability, and clear shake instructions could reduce medication errors. The value is higher in pediatric and caregiver markets.

Abuse-deterrent formulation

A resin system with improved resistance to crushing, extraction, or alcohol-induced dose dumping could support premium positioning. The development cost and regulatory burden would be substantial, and the product would compete against non-opioid antitussives.

Non-opioid substitution

Dextromethorphan, benzonatate, guaifenesin, antihistamine combinations, and prescription non-opioid cough products create substitution pressure. A hydrocodone product remains differentiated by potency but faces tighter prescribing controls and declining opioid utilization.

Contract manufacturing

Manufacturers with expertise in resin complexes, high-viscosity suspensions, and controlled-substance handling could offer development and commercial manufacturing services. This is a specialized niche because ordinary oral-liquid manufacturing capabilities may not translate to reproducible ion-exchange release products.

How does this product compare with competing cough medicines?

Product category	Main advantage	Main limitation	Commercial implication
Hydrocodone/chlorpheniramine ER suspension	Strong cough suppression with extended-release dosing	Schedule II opioid and pediatric restrictions	Niche prescription opportunity
Dextromethorphan products	Non-opioid positioning and broad availability	Abuse potential at high doses; variable efficacy	Lower regulatory burden
Benzonatate	Prescription non-opioid antitussive	Toxicity risk if accidentally chewed or ingested by children	Competes in adult prescription market
Codeine cough products	Established opioid class	Safety, variability, and regulatory restrictions	Declining strategic attractiveness
Guaifenesin combinations	Expectorant positioning and broad consumer use	Not equivalent to opioid antitussive effect	Large-volume substitution market
Non-sedating antihistamines	Lower sedation burden	Limited cough suppression	Relevant for allergy-driven symptoms

The principal commercial constraint is that the product's opioid benefit must justify controlled-substance handling, prescribing limitations, and safety monitoring. The most credible growth strategy is not broad mass-market expansion. It is targeted differentiation through formulation quality, reliable dosing, and controlled distribution.

Key Takeaways

• Hydrocodone polistirex and chlorpheniramine polistirex are extended-release drug-resin complexes used in Tussionex oral suspension.
• The excipient system is built around suspension stability, taste masking, microbial preservation, and controlled redispersion.
• Carrageenan, xanthan gum, polysorbate 80, povidone, polyethylene glycol 3350, sugars, propylene glycol, methylparaben, flavor, and purified water form the key formulation architecture.
• The strongest generic-development risks are bioequivalence, dose uniformity, resuspendability, alcohol interaction, and opioid-compliance requirements.
• Biosimilar competition is irrelevant. The relevant pathway is an ANDA or, for a differentiated product, a separate NDA.
• Ordinary excipients are unlikely to create durable patent barriers. Resin-complex composition, particle engineering, release control, manufacturing process, and dosing-device claims are more important.
• Commercial opportunities include authorized generic supply, sugar-free reformulation, improved dosing systems, abuse-deterrent development, and contract manufacturing.
• FDA pediatric restrictions and Schedule II controls limit broad expansion and favor focused adult prescription-market strategies.

FAQs

Can hydrocodone polistirex be replaced with immediate-release hydrocodone in a generic suspension?

No. A generic product must match the reference product's active ingredients, dosage form, strength, and release characteristics. Immediate-release hydrocodone would generally require a different regulatory strategy.

Is a sugar-free hydrocodone-chlorpheniramine suspension commercially feasible?

Yes, but the developer must address taste, viscosity, preservative efficacy, redispersibility, and bioequivalence. Sugar substitution can materially change the suspension's physical properties.

Does polistirex make hydrocodone abuse-deterrent?

Not automatically. Drug-resin complexation can modify release, but abuse-deterrent status requires evidence under FDA's abuse-deterrence framework and cannot be inferred solely from the presence of polistirex.

What manufacturing capability is required for this product?

The manufacturer needs controlled-substance handling, drug-resin complex processing, high-viscosity oral-suspension manufacturing, particle-size control, preservative testing, and validated dose-uniformity methods.

Could a new flavor or dosing syringe support separate patent protection?

Potentially, but the claim would need meaningful technical novelty and non-obviousness. A flavor change alone is usually a weak patent position. A dosing system that materially improves accuracy or prevents misuse may have stronger device or combination-product value.

References

1. U.S. Food and Drug Administration. (2018). FDA requires labeling changes for prescription opioid cough and cold medicines to limit their use to adults 18 years and older. https://www.fda.gov

2. U.S. Food and Drug Administration. (2023). Tussionex Pennkinetic extended-release suspension prescribing information. https://dailymed.nlm.nih.gov

3. U.S. Food and Drug Administration. (2024a). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book. https://www.fda.gov

4. U.S. Food and Drug Administration. (2024b). Abbreviated new drug application submissions: Refuse-to-receive standards. https://www.fda.gov

5. U.S. Patent and Trademark Office. (2024). Patent term adjustment and patent term extension resources. https://www.uspto.gov