Vial tracking, and what vial supply means for your records

Why vials are harder to keep track of

Some medications come in a pen that counts for you. Others come in a vial, and some of those arrive as a powder. You may need to add liquid, draw with a syringe, and use the vial over several doses.

That means more facts to hold in your head: how much is in the vial, how much liquid went in, how much has been drawn so far, and what remains. A small slip in any of them can make the next dose look different from the last.

Where vials come from

Vials can come from different kinds of supply. Some are made by a manufacturer. Some are prepared by a pharmacy for an individual patient, which is called compounding. Labels, strengths and volumes differ between them.

Reko does not judge, recommend or sell any source. Whatever you have been prescribed or told to use, the record works the same way: you enter what is on your vial, and Reko keeps the count. Questions about a product, its quality or its legal status are for your prescriber and your pharmacist. You can read the current rules from Compounding and the FDA: Questions and Answers.

What Reko keeps for each vial

• The amount of the substance in the vial.
• The liquid added, when the vial was mixed.
• Each dose drawn from it, linked to your dose log.
• What is left, counted down as you log.

The life of a vial on the screen

Each vial shows one of four states. Before you mix it, it reads "Sealed, not yet mixed". Once it is mixed and you log doses, it shows how much is left and how many doses have been drawn. When it is used up it reads "Empty", with the number of doses drawn. If it passes its use-by date, it is marked expired, with the amount that is left to discard.

While a vial is in use, Reko also shows a "use within" line that counts down the days. If you have a schedule for the same compound, it adds a rough "runs out" estimate, so you can plan the next order. The estimate comes from your schedule, so treat it as a planning hint.

Entering a vial

You type the compound, the amount on the label and the unit. There is no cap on vial size. If you have had a vial tested and it differs from the label, you can enter the tested amount as well, and Reko then does all its sums from that number. To record mixing, switch on "Mixed with water", choose the liquid (bacteriostatic water, sterile water or acetic acid), enter how much you added and the date you mixed it. A vial that holds a blend can list each compound, so one injection is logged as one entry. A last section, "Where it came from", is optional. It holds a supplier and a batch code, so you can trace a problem back to one batch if you ever need to.

The use-by date is a convention

Reko sets the use-by date from the date you mixed the vial and the liquid you chose. The figures it uses are conventional ones, not a regulatory standard and not your product's own instructions. They vary by compound and by how a vial is stored. If your label or your pharmacist gives a different time, follow that and not the app.

A worked example of the count

These numbers are made up to show the bookkeeping. They are not a dose and not a suggestion.

• A made-up vial holds 10 mg and has been mixed.
• You log a draw of 2.5 mg. Reko shows 7.5 mg left and one dose drawn.
• You log a second draw of 2.5 mg. It shows 5 mg left and two doses drawn.
• After four such draws the vial reads empty, and the same arithmetic tells you the next draw would not fit.

The reconstitution calculator also warns you when a dose is more than the vial still holds. The count is only as good as the log. If you forget to record a draw, or some liquid is lost, the number on the screen will drift from what is really in the vial. A quick look at the vial against the app, every now and then, catches that early.

The reconstitution calculator

Enter what is in the vial and the liquid you add. Choose the dose you and your prescriber settled on. The calculator shows the number of units to draw on your syringe.

It also warns you when a draw falls between two markings on the syringe. A mark you cannot read exactly is where mistakes tend to start, so the warning is there to make you stop and look again. Check every result against your prescriber's instructions and your own label.

You pick your syringe type (U-100, U-50 or U-40), and the sums change with it, so check the barrel. You can type how much water you added, or let the calculator suggest an amount that puts your chosen dose on an easy-to-read mark. Either way the dose is yours. Under "Check before drawing" it can also flag a draw that is too small to measure by eye, one that will not fit in the syringe, one that is more than the vial holds, and a mix that is so strong that small errors matter more. The same arithmetic, with a worked example, is on the page for the reconstitution calculator.

Pens as well

If you use a pen with clicks, the pen calculator helps you count them for a dose.

When you change vials

A new vial is a good moment for a mistake to slip in. A new vial may have a different strength, or you may mix it with a different amount of water, so the same dose can mean a different mark on the syringe. Enter the new vial before you log from it, and run the numbers again rather than reusing the old mark. If a vial runs out part-way through a dose and the next one has a different strength, the vial transition calculator shows the arithmetic.

A simple routine

1. Add the vial the day it arrives, copying the numbers from the label.
2. Record the date you mix it.
3. Log each dose as you take it.
4. Look at what is left before you plan your next order.
5. Correct any entry if you got it wrong. Doses can be changed on any date.

Open the vial tracker page or see the free tools.

Download Reko

Questions people ask

Does Reko tell me how much to draw?

No. You choose the dose with your prescriber, and the calculator turns it into syringe units. It does not suggest a dose.

Can Reko track a vial that a pharmacy compounded for me?

Yes. You enter what is on your label, and the record works the same way whatever the source. Reko does not judge, recommend or sell any source.

How does Reko know how much is left in a vial?

It subtracts each dose you log from the amount in the vial. It does not measure the vial, so a missed log makes the number wrong.

What if the vial was tested and differs from the label?

You can enter the tested amount, and Reko then calculates from it instead of the label amount.

Why does the calculator warn about syringe markings?

A syringe can only be read at its printed marks. A draw that falls between two marks means guessing the last part of the dose, so the warning prompts you to look again.

How long is a mixed vial good for?

That depends on the product and how it is stored, so follow your label or ask your pharmacist. Reko shows a use-by date from a conventional figure, which is a prompt and not a rule.

Reko records what you decide. It does not suggest a dose and it is not medical advice.

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