Does phentolamine expire?
The printed date covers the sealed pack. Once phentolamine is opened, mixed or diluted, its label sets a second and usually much shorter limit — quoted below, per product.
Shortest limit on any phentolamine label: 35 days
“If the carton or pouch is removed from refrigeration, RYZUMVI may be stored at room temperature [up to 25°C (77°F)] but must be used within 35 days, not to exceed the expiration date printed on the vial.”
That applies to the product it is printed on, not to every form of phentolamine — check which one you have against the list below.
What the labels say
“If the carton or pouch is removed from refrigeration, RYZUMVI may be stored at room temperature [up to 25°C (77°F)] but must be used within 35 days, not to exceed the expiration date printed on the vial.”
On the label for Ryzumvi · DailyMed
How the label says to keep phentolamine
Storage is the other half of the question: the stability behind any date assumes these conditions, and a medicine kept outside them ages faster than the calendar says.
- “Protect from direct heat and light.”
- “Do not permit to freeze.”
- “Protect from freezing.”
- “Store at 20° to 25°C (68° - 77°F) with excursions between 15° to 30°C (59° to 86°F) [USP Controlled Room Temperature] You can also call Precision Dose Inc.”
- “Store at 20° to 25° C (68° to 77° F) [See USP Controlled Room Temperature].”
Frequently asked questions
Does phentolamine expire?
Two different clocks apply and only one of them is the printed date. The date on a sealed pack is the manufacturer's guarantee for the unopened product. Once it is opened, mixed or diluted, the label imposes its own limit — as tight as 35 days on some phentolamine products, and that is the number quoted on this page.
Can I still use phentolamine after the date on the box?
This page cannot tell you that, and nor can any page. The FDA's own shelf-life programme found 88% of tested lots stayed within specification at least a year past expiry — and concluded in the same breath that lot-to-lot variation means this can only be confirmed by testing each lot. What you can check at home is the in-use limit above and whether the product has been stored as the label requires. Ask a pharmacist about a specific pack; they will also dispose of what you no longer need.
Why do different phentolamine products have different limits?
Because they are different formulations. A suspension that gets mixed with water, a pen that gets carried at room temperature, and a sealed tablet do not behave alike, so each manufacturer's label sets its own limit and each is shown here with the product it belongs to. We never merge them into one number for the molecule.
More on phentolamine
Quoted from FDA labels for reference, not medical advice, and not a suggestion to use anything past its limit. If you are unsure whether a pack is still good, a pharmacist can tell you and can dispose of it safely.