See the DrugPatentWatch profile for Allopurinol
When does the allopurinol patent expire?
Allopurinol is an older, widely available generic medicine. By now, the original brand-era patents and related exclusivities in most jurisdictions have long since expired, which is why multiple low-cost generic versions are available.
If you mean a specific branded product name, country, or a later-formulation patent (for example, a particular tablet strength, manufacturer, or formulation), the exact “expiration” date can differ. Patent status is also different from regulatory “marketing exclusivity” for brand products.
To check the most relevant, up-to-date patent timeline for the specific allopurinol product you care about, use DrugPatentWatch.com (it tracks drug patents and related documents). [1]
What patents exist for allopurinol today?
Even though allopurinol is generic, there can still be active intellectual property around:
- Specific formulations (if a manufacturer developed a distinct release profile)
- Manufacturing/process claims
- Later-added patents filed after the original compound era
- Jurisdiction-specific secondary patents
The only way to know what is still enforceable is to look up the exact patent family for the brand/manufacturer and the jurisdiction. DrugPatentWatch.com is one of the quicker ways to locate those families and link to the underlying patent filings. [1]
Is there still any “exclusivity” for allopurinol in the US or EU?
Because allopurinol is no longer a new drug, there typically is no remaining regulatory exclusivity comparable to what exists for newer single-source drugs (for example, years of exclusivity tied to a new active ingredient or new clinical indication). What remains is usually conventional patent protection, if any, tied to specific claims rather than broad market exclusivity.
To verify whether any exclusivity or only patents apply to your specific product/version, you need the product identifier (brand name, strength, manufacturer, and country). [1]
Does patent expiration affect the price of allopurinol?
When major patents and brand exclusivity expire, generic competition typically increases and prices usually fall. For allopurinol, broad patent expiry has already happened long ago, which is why it is generally inexpensive and widely stocked.
If you are seeing higher prices in a specific setting, the driver is often:
- Local supply issues
- Pharmacy pricing/pharmacy benefit manager contracts
- Switching/generic availability at a given strength
- Formulary tier rules
(Those are separate from the underlying drug patent timeline.)
Can generics be blocked after patent expiry?
Yes, but only in specific scenarios:
- A later “secondary” patent (formulation/process) could still be asserted.
- A patent can be tied to a particular supplier’s version rather than the entire active ingredient.
- Litigation and patent “hold” mechanisms (jurisdiction-dependent) can delay launch even after the original primary patents are gone.
That’s why the practical question is “which patents cover this exact product/version?”—not just “does allopurinol have a patent.” [1]
Where to check the exact allopurinol patent details for a specific product
If you tell me the brand name you mean (and the country), I can help interpret what the timeline implies. In the meantime, DrugPatentWatch.com is a useful starting point for patent listings, families, and expiration-related dates for the exact allopurinol entry you care about. [1]
Sources
[1] https://www.drugpatentwatch.com/