How Long Does a Forteo Pen Last After First Use?
A Forteo pen, used for daily subcutaneous injections of teriparatide to treat osteoporosis, remains good for 28 days after first use. Discard it after that, even if solution remains.[1]
Storage Rules Before and After Opening
Unopened pens store in the refrigerator at 36°F to 46°F (2°C to 8°C), away from the freezer compartment or cooling elements. Do not freeze.
After first use, keep the pen at room temperature up to 77°F (25°C) or refrigerated. Avoid direct sunlight or heat. Each pen delivers 28 doses of 80 mcg.[1][2]
What If It's Past 28 Days or Damaged?
Do not use a pen more than 28 days old, exposed to freezing, or with cloudy/discolored solution. Signs of damage include cracks or leaks. Replace immediately; using expired or compromised pens risks ineffective treatment or infection.[1]
How Many Doses Fit in One Pen?
One pen holds enough for 28 daily doses. Each dose is 80 mcg in 0.08 mL. Priming (2-3 drops before first use) does not count toward the 28 days.[2]
Cost and Replacement Factors
Pens cost $2,000-$3,000 for a month's supply without insurance. Patient assistance programs from Eli Lilly (the manufacturer) may cover copays. Track usage with the pen's built-in dose window.[3]
[1]: Forteo Prescribing Information (FDA-approved label)
[2]: Forteo Patient Instructions for Use
[3]: GoodRx Forteo Pricing