Ostin

How long will my vial last?

For a multi-dose vial of compounded tirzepatide or semaglutide.

mL in the vial
mg per mL, from the label
mg per shot
Days between shots
Days after opening, if your pharmacy gave a beyond-use date

Assumes the same dose each time. Vials lose a little to priming and air bubbles, so plan to reorder before the last dose. Follow your pharmacy's storage and discard instructions.

How it's worked out

The medicine in the vial is mL × mg/mL: a 2 mL vial at 10 mg/mL holds 20 mg. Divide by your dose for the number of full doses: 20 mg ÷ 2.5 mg = 8 doses, about 8 weeks of weekly shots.

When the dose goes up

A vial runs out faster after a step up. At 5 mg the same 20 mg vial is 4 doses. If your plan steps up soon, enter the higher dose too and plan the refill around it.

Beyond-use dates

Compounded vials often come with a date to discard them, commonly a few weeks after opening, even if medicine is left. If that comes first, it's when you'll need the next vial.

Let your iPhone keep track

Ostin tracks your shots, dose steps, supply, protein and site rotation, and reminds you on shot day. No account, no subscription.

Join the free beta

For iPhone, through Apple's TestFlight app; spots are limited.

More tools: Units to mg · Protein goal · Site rotation