How long will a vial last?
Vial in micrograms, divided by your dose. A 10mg vial at 250mcg is 40 doses: under six weeks daily, five months at twice a week.
Two separate questions
People conflate them. The first is how many doses are in the vial, which is pure arithmetic. The second is how long the liquid stays good once mixed, which is not an arithmetic question at all and depends on the compound and your storage.
Doses per vial
| Vial | In micrograms | At 250mcg | At 500mcg | At 1,000mcg |
|---|---|---|---|---|
| 5mg | 5,000mcg | 20 doses | 10 doses | 5 doses |
| 10mg | 10,000mcg | 40 doses | 20 doses | 10 doses |
| 15mg | 15,000mcg | 60 doses | 30 doses | 15 doses |
| 30mg | 30,000mcg | 120 doses | 60 doses | 30 doses |
Note the water volume appears nowhere in that table. Adding more water does not create more substance; it spreads the same amount over more liquid, so each dose takes more clicks. Doses per vial is fixed the moment you know the vial size and your dose.
Doses per cartridge
This one does depend on the water, because a 3ml cartridge is a fixed volume. Divide 300 by your dose in units. A 5-unit dose gives 60 doses from a full cartridge; a 20-unit dose gives 15.
So a 10mg vial mixed into 2ml is 40 doses of substance sitting in 2ml of liquid, which fits in one cartridge with room to spare. Mixed into 4ml, the same 40 doses need two cartridges.
The bit that is not arithmetic
How long reconstituted liquid remains good is a property of the compound, the preservative in your water and your storage, and it is outside what an equipment retailer can advise on. Practically, most people mix a quantity they will get through in a sensible window rather than filling every cartridge they own at once.
The dosing planner does all of this and adds a calendar, including the date to reorder by so you are not left without a clean cartridge.
Questions
- Does adding more water make a vial last longer?
- No. It changes how many clicks a dose takes, not how much substance is in the vial. Doses per vial is the vial divided by the dose, full stop.
- How many injections from a 3ml cartridge?
- 300 divided by your dose in units. Five units gives sixty, ten units gives thirty, twenty units gives fifteen.