Last updated: September 24, 2026

The aspirin, caffeine, and dihydrocodeine bitartrate combination is an established prescription analgesic marketed in the United States as Synalgos-DC. Its commercial position is constrained by opioid regulation, limited prescribing, generic substitution, and competition from non-opioid migraine and pain treatments. The product has no visible protection from a modern patent estate, no meaningful biologic or biosimilar issue, and limited public evidence of material product-level revenue.

The commercial outlook is mature to declining. Any remaining value is concentrated in a narrow prescription market, legacy brand recognition, distributor access, and the clinical utility of a fixed-dose combination for acute pain.

What is the aspirin, caffeine, and dihydrocodeine bitartrate drug?

The product combines three active ingredients:

Component	Function
Aspirin	Nonsteroidal analgesic and antipyretic
Caffeine	Analgesic adjuvant that can enhance pain relief
Dihydrocodeine bitartrate	Opioid analgesic

Synalgos-DC capsules contain 356.4 mg of aspirin, 30 mg of caffeine, and 16 mg of dihydrocodeine bitartrate per capsule, according to the U.S. prescribing information.[1]

The product is indicated for the relief of moderate to moderately severe pain. Its opioid component exposes the product to controlled-substance rules, abuse-deterrence scrutiny, opioid-prescribing restrictions, and heightened pharmacy controls.

What is the FDA regulatory status?

The product was approved through the new drug application pathway rather than the modern abbreviated new drug application system used for most generic products. The FDA labeling identifies Synalgos-DC as a prescription product containing an opioid analgesic.[1]

The FDA’s regulatory position is affected by:

Controlled-substance scheduling for dihydrocodeine combinations
Opioid labeling requirements
Medication Guide and abuse, misuse, and addiction warnings
Respiratory-depression risks
Restrictions involving concomitant sedatives and alcohol
State-level prescription-monitoring and opioid-dispensing rules

The product is not a biologic. Biosimilar competition is therefore not relevant.

How does the aspirin-caffeine-dihydrocodeine combination work?

The combination uses complementary mechanisms. Aspirin inhibits cyclooxygenase-mediated prostaglandin production. Caffeine may improve analgesic response and counter some opioid-related sedation. Dihydrocodeine produces opioid-mediated analgesia through central nervous system activity.

The formulation is positioned for acute pain rather than chronic disease management. Its clinical use is limited by the risks associated with aspirin and dihydrocodeine, including gastrointestinal bleeding, respiratory depression, dependence, impaired driving, and overdose.

The fixed-dose format may be convenient, but it also limits prescriber flexibility. A clinician cannot independently adjust the opioid, non-opioid, and caffeine components.

What patents protect Synalgos-DC and its active ingredients?

The core composition is an old drug combination with no evident modern patent barrier protecting commercial entry. Aspirin, caffeine, and dihydrocodeine are long-established active ingredients. Any original composition, formulation, or use patents would have expired decades ago.

What is the Orange Book status?

The FDA Orange Book is the primary U.S. source for patents and regulatory exclusivity associated with approved drug products.[2] The product does not appear to have a commercially relevant current patent estate comparable to newer branded drugs.

The practical conclusions are:

Patent issue	Commercial assessment
Core composition patent	Expired or unavailable as a current barrier
Active-ingredient patents	Expired
Modern formulation patents	No material protection identified
Method-of-use patents	No material protection identified
Orange Book patent dispute	No significant current dispute identified
Regulatory exclusivity	Expired
Generic entry barrier	Primarily regulatory, manufacturing, and market-based

The absence of an active patent estate does not guarantee rapid generic entry. Controlled-substance manufacturing, formulation stability, FDA review, supply-chain controls, and limited market size can discourage competitors even where patent protection is absent.

How strong is the patent estate?

The patent estate is weak from a life-cycle-management perspective. The product lacks the characteristics that support extended exclusivity:

No active molecular patent
No long-lived delivery technology
No biologic manufacturing complexity
No high-value disease-specific indication
No obvious pediatric or orphan exclusivity strategy
No active formulation franchise comparable to extended-release opioid products

Any remaining commercial defensibility is operational rather than patent-based.

When does aspirin, caffeine, and dihydrocodeine lose exclusivity?

The product’s meaningful exclusivity period ended long ago. It is not positioned as a recently launched protected medicine, and its commercial life is based on legacy approval and continued availability rather than patent exclusivity.

Exclusivity category	Status
New chemical entity exclusivity	Expired
Original product patent	Expired
Pediatric exclusivity	None of current commercial significance
Orphan exclusivity	Not applicable
Qualified infectious-disease exclusivity	Not applicable
GAIN Act exclusivity	Not applicable
Current market exclusivity	None of material duration

The key entry question is therefore not when exclusivity expires. It is whether a manufacturer can justify the cost and compliance burden of supplying a small opioid-combination market.

Are there generic versions of Synalgos-DC?

Generic availability has historically been limited compared with common products such as codeine-acetaminophen or butalbital-acetaminophen-caffeine combinations. The market may include authorized or therapeutically similar supply depending on the period, distributor, and FDA-listed product status.

A competitor would need to address:

ANDA approval requirements.
Demonstration of pharmaceutical equivalence and bioequivalence.
Controlled-substance registration and quota management.
DEA compliance.
Opioid manufacturing and distribution controls.
Commercial distribution through wholesalers and pharmacies.
Product liability and abuse-diversion exposure.

The small market can weaken the business case for multiple generic entrants. Generic competition can also create supply instability if one or two suppliers exit.

What Paragraph IV challenges affect the product?

No prominent current Paragraph IV campaign is associated with the aspirin-caffeine-dihydrocodeine combination. That result is consistent with the product’s age and lack of a commercially important unexpired patent estate.

A Paragraph IV filing is most valuable where an active patent blocks a large market. This product does not present that profile. A potential entrant would more likely rely on ordinary generic approval, product discontinuation status, or an unpatented competitive pathway than on high-value patent litigation.

What patent litigation affects Synalgos-DC?

No major active patent litigation appears to define the commercial outlook for Synalgos-DC. The product’s legal exposure is more likely to arise from opioid marketing, controlled-substance compliance, product liability, and labeling enforcement than from patent infringement.

Potential legal risks include:

Failure to comply with DEA controlled-substance requirements
Improper distribution or diversion
Inadequate opioid-risk warnings
Aspirin-related gastrointestinal injury claims
Respiratory depression or overdose claims
Alleged promotion outside the approved indication
Pharmacy and wholesaler compliance actions

These risks affect operating cost and liability reserves but do not create patent-based market exclusivity.

How does opioid regulation affect market dynamics?

Opioid regulation is the central market constraint. Dihydrocodeine products face a more difficult commercial environment than non-opioid analgesics because prescribers, pharmacies, payers, and distributors have adopted stricter controls.

The product is affected by:

State prescription-drug-monitoring programs
Limits on initial opioid prescriptions
Electronic prescribing requirements
Quantity restrictions
Prior authorization
Prescriber reluctance
Pharmacy refusal or limited stocking
Wholesaler due diligence
DEA production quotas

The combination also contains aspirin, which creates a separate risk profile. Aspirin can cause gastrointestinal ulceration and bleeding, particularly in older adults, patients using anticoagulants, and patients with a history of peptic ulcer disease.

This dual-risk profile reduces the number of patients for whom the product is an attractive first-line option.

What is the competitive landscape?

The product competes across several therapeutic categories rather than against one direct substitute.

Competitive category	Examples	Competitive effect
Non-opioid analgesics	Ibuprofen, naproxen, acetaminophen	Preferred for lower-risk acute pain
Opioid combinations	Hydrocodone-acetaminophen, oxycodone-acetaminophen, codeine combinations	Compete for opioid-treated pain
Migraine combinations	Acetaminophen-caffeine combinations, triptan products	Reduce demand where migraine-specific therapy is appropriate
Nonprescription products	Aspirin, acetaminophen, ibuprofen, caffeine combinations	Pressure prescription demand
Newer migraine therapies	CGRP antagonists and monoclonal antibodies	Replace older analgesic approaches in selected patients
Nonpharmacologic treatment	Physical therapy and procedural interventions	Reduce long-term analgesic use

The product has limited differentiation. Caffeine is a familiar analgesic adjuvant, and dihydrocodeine does not provide a durable commercial advantage over more commonly prescribed opioid alternatives.

What is the financial trajectory for the product?

Public company filings do not generally disclose revenue for Synalgos-DC as a standalone product. The financial trajectory must therefore be assessed using product age, prescription dynamics, regulatory burden, and competitive intensity rather than a verified product-level revenue series.

The likely trajectory is:

Period	Financial profile
Historical launch and maturity	Revenue supported by prescription analgesic demand and limited alternatives
Generic and post-patent period	Price pressure and reduced brand leverage
Opioid-restriction period	Lower prescribing, greater compliance expense, narrower distribution
Current mature stage	Low-growth or declining demand with episodic supply opportunities
Longer term	Continued niche use, subject to discontinuation and supplier economics

What revenue exposure does the product create?

The product is unlikely to be a material revenue driver for a diversified pharmaceutical company. Its value is more relevant to a specialty or generic manufacturer with:

Existing controlled-substance infrastructure
Low incremental manufacturing costs
Established wholesale access
Ability to manage DEA quotas
A portfolio that shares regulatory and distribution resources

For a large innovator, the product would generally have limited strategic value. For a small generic company, it could provide modest niche revenue if competition is limited and supply remains reliable.

Revenue is exposed to several downward pressures:

Declining opioid utilization
Substitution with non-opioid therapies
Payer restrictions
Generic price erosion
Pharmacy stocking decisions
Product discontinuation risk
Compliance expenses
Potential liability costs

The main upside is shortage-driven pricing or limited competition. That upside is intermittent and does not support a conventional high-growth forecast.

What manufacturing and intellectual-property barriers exist?

Manufacturing complexity is moderate rather than high. The product is an immediate-release oral capsule with established active ingredients. It does not require biologic cell culture, sterile injectable production, complex device assembly, or advanced delivery technology.

The principal barriers are operational:

Controlled-substance handling
Accurate dosing of three active ingredients
Content uniformity
Stability and impurity control
Secure warehousing
DEA registration and quota management
Anti-diversion procedures
Reliable supply of dihydrocodeine bitartrate
Batch-release and quality systems

These barriers can reduce the number of active suppliers, but they are not equivalent to patent protection. A manufacturer with the right infrastructure can potentially enter without negotiating a license from an innovator.

Are there licensing deals associated with the product?

No major current licensing transaction appears to determine the economics of the aspirin-caffeine-dihydrocodeine combination. The product is not associated with a contemporary platform technology, co-development arrangement, or high-value regional licensing structure.

Any commercial transfer would likely involve:

Product rights
NDA or abbreviated-approval rights
Manufacturing rights
Controlled-substance registrations
Inventory and distribution agreements
Brand and trademark rights

The value of such a transaction would depend on current supply status and prescription volume, not on patent life.

How does this product compare with newer analgesic products?

Attribute	Aspirin/caffeine/dihydrocodeine	Newer non-opioid or targeted therapies
Patent protection	Minimal or expired	Often active
Regulatory burden	High because of opioid content	Varies, often lower
Prescriber acceptance	Narrowing	Stronger in targeted indications
Pricing power	Low	Potentially higher
Manufacturing complexity	Moderate	May be high for biologics or devices
Abuse liability	Present	Usually lower
Revenue growth	Mature or declining	Higher where clinical differentiation exists
Generic pressure	High	Depends on patent status

The product retains a role where clinicians seek a combination analgesic for acute moderate pain, but its clinical and commercial relevance is narrower than it was before modern opioid controls and expanded non-opioid treatment options.

What generic launch scenarios exist?

Three scenarios are commercially plausible.

Limited-entry scenario

One supplier remains active, with intermittent shortages and modest price stability. The product survives as a niche controlled-substance offering.

Multi-generic scenario

Two or more manufacturers obtain approval or maintain supply. Wholesale prices fall, pharmacy substitution rises, and the branded product loses most remaining value.

Discontinuation scenario

Manufacturing, compliance, or liability costs exceed expected demand. The brand or generic product is discontinued, leaving sporadic availability or therapeutic substitution.

The discontinuation scenario is credible for mature controlled-substance products with low prescription volume and limited strategic importance.

What is the geographic coverage?

The main commercial market is the United States, where the product has an FDA approval history and controlled-substance framework. International availability varies because dihydrocodeine scheduling, opioid prescribing, and product approvals differ by jurisdiction.

Geographic expansion would require:

Country-specific marketing authorization
Controlled-substance permits
Local labeling
Import and export approvals
Pharmacovigilance systems
Distribution controls
Local reimbursement access

The lack of a current patent estate makes geographic expansion legally easier than for a new medicine, but the market opportunity is limited by opioid restrictions and established local alternatives.

Key Takeaways

The aspirin, caffeine, and dihydrocodeine bitartrate combination is a mature prescription analgesic marketed in the United States as Synalgos-DC.
The product contains 356.4 mg of aspirin, 30 mg of caffeine, and 16 mg of dihydrocodeine bitartrate per capsule.
Core composition and formulation protection are expired or commercially immaterial.
No significant current Paragraph IV campaign, patent litigation, or licensing transaction defines the market.
Biosimilar competition is irrelevant because the product is a small-molecule oral combination.
Opioid regulation, pharmacy restrictions, and prescriber caution are stronger commercial constraints than intellectual property.
Public sources do not establish a standalone product revenue series.
The financial trajectory is mature to declining, with limited upside from supply shortages or constrained generic competition.
The main commercial risks are discontinuation, substitution by non-opioid therapies, compliance cost, and liability exposure.
The product may retain niche value for a manufacturer with existing controlled-substance infrastructure, but it is unlikely to be a major growth asset.

Frequently Asked Questions

Is aspirin, caffeine, and dihydrocodeine bitartrate still prescribed?

Yes, where the product is available and clinically appropriate, but prescribing is constrained by opioid controls, adverse-effect risks, and competition from non-opioid analgesics.

Is Synalgos-DC a Schedule II opioid?

The product’s controlled-substance classification is determined by the dihydrocodeine combination and applicable federal scheduling rules. Its regulatory treatment is less commercially important than the general opioid controls governing prescribing, dispensing, and distribution.[3]

Can a company launch a generic without licensing the brand?

A company may pursue an applicable FDA approval pathway without obtaining a brand license when no enforceable patent or exclusivity blocks approval. It still must satisfy FDA quality, bioequivalence, labeling, and controlled-substance requirements.

Does caffeine make dihydrocodeine more effective?

Caffeine is included as an analgesic adjuvant and may enhance the perceived or measured effect of some analgesic combinations. The combination does not eliminate opioid risks or justify use where the opioid is clinically inappropriate.

What is the largest commercial threat to Synalgos-DC?

The largest threat is declining clinical demand caused by opioid stewardship and substitution with non-opioid or indication-specific therapies. Generic price competition and possible supplier withdrawal are secondary threats.

References

U.S. Food and Drug Administration. (n.d.). Synalgos-DC prescribing information: Aspirin, caffeine, and dihydrocodeine bitartrate capsules.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, 44th edition.
U.S. Drug Enforcement Administration. (2024). Controlled substances schedules.

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
DailyMed Link:	aspirin; caffeine; dihydrocodeine bitartrate at DailyMed

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Sun Pharm Industries	SYNALGOS-DC	aspirin; caffeine; dihydrocodeine bitartrate	CAPSULE;ORAL	011483-004	Sep 6, 1983		DISCN	Yes	No	⤷ Start Trial	⤷ Start Trial				⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Exclusivity Expiration

Aspirin; caffeine; dihydrocodeine bitartrate - Generic Drug Details

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