Short answer: Store Estring at controlled room temperature, 59-77°F (15-25°C). Store Femring at 68-77°F (20-25°C), with excursions allowed from -4°F to 104°F (-20°C to 40°C); keep it in its pouch and insert it right after taking it out. Neither label calls for refrigeration. Sources: Estring label, How Supplied and patient leaflet; Femring label, section 16 and patient leaflet.
| Product | Temperature | Packaging |
|---|---|---|
| Estring (2 mg estradiol, 7.5 mcg per day over 90 days) | Controlled room temperature, 15-25°C (59-77°F) | One ring per pouch |
| Femring 0.05 mg/day and 0.10 mg/day | 20-25°C (68-77°F); excursions -20°C to 40°C (-4°F to 104°F) | One ring per pouch; do not store unpouched |
Femring, section 16.2: “Store at 20º C to 25º C (68º F to 77º F); excursions permitted to -20º C to 40º C (-4º F to 104º F). Do not store unpouched. Insert immediately upon removal from the protective pouch.”
Estring: “Store at controlled room temperature 15° to 25 °C (59 °F to 77 °F).” The Estring label gives no excursion range and does not say whether the ring may be stored out of its pouch.
Estring patient leaflet: “Discard the used ring in a waste receptacle. (Do not flush ESTRING.)” Femring patient leaflet: “Wrap the used ring in tissue or toilet paper and put it in a trash can.”
Femring leaflet: if the ring comes out before 90 days, clean it with warm water and put it back in. Contact with blood may discolor Femring during use; the leaflet says this does not affect how it releases medicine. Both labels say to keep the ring out of the reach of children; the Estring pouch says the package is not child-resistant.
See Estring side effects, Femring side effects, the Estring and Femring dosing schedules, and the vaginal estradiol page.
Both are room-temperature products, so they need no ice pack. Keep a spare ring sealed in its pouch in your carry-on and out of a hot car: up to 77°F (25°C) for Estring, and within the -4°F to 104°F (-20°C to 40°C) excursion range for Femring.