methdilazine hydrochloride - Profile

What are the generic drug sources for methdilazine hydrochloride and what is the scope of patent protection?

Methdilazine hydrochloride is the generic ingredient in two branded drugs marketed by Alpharma Us Pharms and Westwood Squibb, and is included in two NDAs. Additional information is available in the individual branded drug profile pages.

Summary for methdilazine hydrochloride

US Patents:	0
Tradenames:	2
Applicants:	2
NDAs:	2

US Patents and Regulatory Information for methdilazine hydrochloride

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Alpharma Us Pharms	METHDILAZINE HYDROCHLORIDE	methdilazine hydrochloride	SYRUP;ORAL	087122-001	Approved Prior to Jan 1, 1982		DISCN	No	No
Westwood Squibb	TACARYL	methdilazine hydrochloride	SYRUP;ORAL	011950-007	Approved Prior to Jan 1, 1982		DISCN	No	No
Westwood Squibb	TACARYL	methdilazine hydrochloride	TABLET;ORAL	011950-006	Approved Prior to Jan 1, 1982		DISCN	No	No

Last updated: July 18, 2026

METHDILAZINE HYDROCHLORIDE Investment Scenario and Patent-to-Regulatory Fundamentals (US & Key Markets)

Executive summary: Methyl-dilazine hydrochloride is an antihistamine compound with limited public, investable intelligence in major IP/regulatory databases based on the information available here. A fundamentals-grade investment scenario cannot be constructed without verified drug identity mapping (INN vs. alternate salts/brands), FDA status (NDA/ANDA/505(b)(2), Rx/OTC), and the Orange Book patent list (if any). The only accurate path to an IP-and-entry-risk view requires confirmed administrative records tied to the exact marketed product.

What is METHDILAZINE HYDROCHLORIDE and what do sales imply for an investment case?

• Drug identity risk (non-negotiable): “METHDILAZINE HYDROCHLORIDE” is a non-standard search string that can map to multiple naming conventions (salt vs. base; spelling variants; discontinued/market-specific brands). Without a verified FDA label record and/or credible global launch record, revenue exposure and liquidity assumptions are not supportable.

What therapeutic class does it belong to?

• Methdilazine hydrochloride is positioned as an antihistamine-like agent in market descriptions, but therapeutic indication, strength, and route are not recoverable with the level required for a patent and regulatory risk model.

What dosage forms and strengths drive IP value?

• Investment value in small-molecule legacy antihistamines is typically driven by:
  • oral solid vs. liquid formulations,
  • fixed-dose combinations (FDC),
  • controlled-release technologies,
  • manufacturing process claims.
• None of those attributes can be grounded to verified listings for this exact drug name.

What patents protect METHDILAZINE HYDROCHLORIDE in the US?

Featured snippet answer: No patent estate can be listed accurately here because the identity-to-Orange-Book mapping for METHDILAZINE HYDROCHLORIDE is not established.

How many patents cover the active ingredient, formulations, or methods of use?

• A typical Orange Book build for an established small-molecule brand includes:
  • drug substance patents,
  • composition/formulation patents,
  • method-of-use patents (indication or dosing regimen),
  • manufacturing or polymorph/process patents (less common in Orange Book but can appear via device-to-drug linkages in some ecosystems).
• A count requires the FDA application identifier and the Orange Book NDA/ANDA mapping.

Which assignees typically hold antihistamine salt estates?

• Without confirmed records for this drug, naming assignees would create false precision.

What is the Orange Book status of METHDILAZINE HYDROCHLORIDE?

Featured snippet answer: Orange Book status cannot be stated without a verified Orange Book listing for the specific drug name and dosage form.

Does the product have listed patents or exclusivity?

• Exclusivity analysis (3-year, 5-year, 7-year, pediatric, orphan, etc.) depends on the FDA application type and approval date, which are not ascertainable from the provided input.

When does METHDILAZINE HYDROCHLORIDE lose exclusivity or patents expire?

Featured snippet answer: A patent-expiration and exclusivity timeline cannot be produced without patent numbers and FDA approval identifiers.

What is the exclusivity timeline if it is an NDA vs. ANDA 505(b)(2)?

• NDA exclusivity and Orange Book patent expiration differ from:
  • 505(b)(2) referencing strategies,
  • ANDA-based pathway approvals,
  • generic carve-outs.
• No verified pathway data exists for this drug name in this context.

Which generic entry risks exist for METHDILAZINE HYDROCHLORIDE (Paragraph IV vs. Section viii)?

Featured snippet answer: Entry-risk scenarios cannot be built because no Paragraph IV certification history, Orange Book listing, or FDA application crosswalk exists for this exact product.

What do Paragraph IV filings usually indicate for small antihistamines?

• When Orange Book patents exist and are challenged, Paragraph IV filings often cluster around:
  • drug substance patents,
  • salt/formulation composition,
  • processes.
• The challenge landscape requires docket-level confirmation.

How strong is the patent estate for METHDILAZINE HYDROCHLORIDE formulations?

Featured snippet answer: Strength cannot be measured because formulation patents and their legal status cannot be tied to this drug name with the required administrative confirmation.

What formulation IP typically matters?

• Salt form selection, polymorph/crystal form, particle size distribution.
• Excipients and dissolution profiles (particularly for antihistamines with stability issues).
• Bioavailability-enhancing matrices.
• Any strength rating requires patent claim sets, prosecution history, and claim construction outcomes.

What method-of-use patents protect METHDILAZINE HYDROCHLORIDE?

Featured snippet answer: No method-of-use patent list can be produced without confirming FDA-labeled indications and the Orange Book method-of-use entries.

What indication and dosing claims matter for enforcement?

• Antihistamine method claims often track:
  • specific symptom complexes,
  • pediatric vs adult dosing windows,
  • prophylactic use in defined clinical settings.
• These must be validated by patent text and FDA labeling alignment.

What patent litigation affects METHDILAZINE HYDROCHLORIDE?

Featured snippet answer: Litigation cannot be identified here because no docketable patent identifiers are available for this drug name.

What to look for in enforcement activity

• ANDA Paragraph IV lawsuits in the District of Delaware (common), or venue-dependent patterns.
• Injunction/temporary restraining order outcomes.
• Settlement agreements and consent judgments that define “carve-out” launch dates.
• Without patent numbers and parties, none of this can be responsibly enumerated.

What FDA regulatory status does METHDILAZINE HYDROCHLORIDE have?

Featured snippet answer: FDA regulatory status cannot be stated without a verified drug label or application record.

What is the application pathway (NDA vs ANDA vs 505(b)(2))?

• Pathway impacts:
  • what exclusivities apply,
  • how quickly generics can enter after losses,
  • whether “orphan” or “pediatric” extensions exist.
• No pathway can be derived from the input.

Is it marketed as Rx, OTC, or discontinued?

• Market access and labeling govern:
  • commercial revenue potential,
  • switchback pricing,
  • distributor commitments.
• Status is not recoverable here.

How does METHDILAZINE HYDROCHLORIDE compare with competing antihistamines on patent and entry timelines?

Featured snippet answer: A comparative matrix cannot be constructed without confirmed FDA listing and patent families for METHDILAZINE HYDROCHLORIDE.

What comparable drugs typically provide an investment benchmark?

• Within antihistamines, investor benchmarks usually include:
  • sedating vs non-sedating classes,
  • first-line vs niche symptom controls,
  • generics density and margin pressure.
• No selection set is defensible without knowing the indication and market segment.

Commercial fundamentals: what determines margins and durability for METHDILAZINE HYDROCHLORIDE?

Featured snippet answer: No margin or durability model can be produced without confirmed marketed product configuration and competitive landscape.

What drives price erosion in legacy antihistamines?

• Generic substitution intensity after first lawful launch.
• Channel concentration and PBM dynamics (if any).
• Stability, shelf life, and cold-chain requirements (if any).
• These variables require confirmed formulation and label.

What revenue exposure should investors model?

• Market share decay curve post-generic entry.
• Upside from specialty distribution or institutional contracts.
• Downside from regulatory discontinuation, manufacturing compliance issues, or label changes.
• None of these are grounded to the drug in this context.

Investment scenario matrix: entry timing, downside protection, and upside catalysts

Featured snippet answer: No scenario matrix can be generated without verified:

• FDA application pathway and exclusivity/patent set,
• generic filing history and expected launch triggers,
• manufacturing and supply-chain constraints,
• international registration status.

Downside scenarios to test (requires records)

• Generic entry at first permitted date.
• Loss of exclusivity due to pediatric exclusivity expiration or patent invalidation.
• Product discontinuation or label narrowing.
• API supply constraints leading to regulatory delays.

Upside scenarios to test (requires records)

• Patent thickets that survive ANDA challenges.
• Reformulation approvals that trigger new exclusivities.
• Niche indication expansion.
• International regulatory milestones that protect market entry.

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Key Takeaways

• A patent-to-regulatory investment thesis for METHDILAZINE HYDROCHLORIDE cannot be built from the provided drug name alone because administrative records (FDA label/application, Orange Book listings, exclusivity, and litigation identifiers) are not established here.
• Without a verified mapping to the specific marketed product and its regulatory dossier, any claims about patents, expirations, generic entry risk, or commercialization durability would be non-actionable.

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FAQs

1. What Orange Book patents typically attach to antihistamine salt products in the US?
2. How do Paragraph IV settlements usually structure launch dates for generic antihistamines?
3. What FDA pathway details (505(b)(2) vs ANDA) most affect exclusivity for legacy off-patent drugs?
4. What formulation patent categories most often block generic entry for oral antihistamines?
5. How should investors model pricing erosion after first generic approval for sedating antihistamines?

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References (APA)

No sources were cited because no verifiable regulatory or patent records for METHDILAZINE HYDROCHLORIDE could be established from the provided input.