How long can Novolin R stay out of the fridge?
Novolin R (regular human insulin)
It depends on the device: vial 42 days, flexpen 28 days at room temperature, opened or not. After that, throw it out even if insulin is left.
- Vial
- 42 days
- FlexPen
- 28 days
Good to know
- Before opening, keep it in the fridge (36°F to 46°F) until the expiration date on the box.
- Keep below 86°F (30°C), away from heat and direct light. Never freeze; throw out insulin that froze.
- Whether an opened pen can go back in the fridge depends on the product. Check the label.
Source: the FDA label on DailyMed, last checked October 14, 2026. Labels change, so check the product in hand. Questions about a patient's medicine go to the pharmacist.
Working out the days supply?
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