How it works

From two numbers to a finished dose

Nettle carries you from reconstitution math through drawing, logging, reminders, and weigh-ins — one flow, not five separate screens.

Start with what you already know

You enter the vial's strength and the dose you want. Instead of asking you to guess a water volume first, Nettle solves for it — choosing an amount that lands your draw on a clean, round-unit mark on a standard syringe.

Vial strength
10 mg
Desired dose
2.5 mg
Water to add
1.58 mL

That water volume, and the resulting draw, are what the rest of the walkthrough is built around — the diagrams and captions in the next step use your actual numbers, not a generic example.

The reconstitution guide

Nine steps, captioned with your numbers

Each step pairs a photo reference with the specific volume, count, or instruction your calculation produced — so you're never translating a generic guide into your own math mid-injection.

Swab the BAC water vial

Wipe the rubber stopper with an alcohol swab and let it dry before drawing.

Draw the BAC water

Draw the exact volume Nettle calculated for you — shown as a caption under this step, with multi-draw instructions if the volume needs more than one syringe fill.

Swab the peptide vial

Wipe the peptide vial's stopper the same way, and let it dry.

Insert the needle

Insert at an angle against the rubber stopper, bevel up, to keep the puncture clean.

Inject the water

Push the plunger slowly, aiming the stream along the inside wall of the vial rather than directly at the lyophilized powder.

Swirl, don't shake

Gently swirl the vial in a circular motion until the powder is fully dissolved. Shaking can damage the peptide — a common-mistake callout flags this directly on this step.

Inspect the solution

Check that the liquid is clear, with no visible particles or cloudiness, before drawing your dose.

Draw your dose

Draw to the unit mark Nettle calculated for the dose you entered at the start.

Inject

Administer per your prescriber's instructions on site and technique.

After the injection

The flow keeps going — it doesn't stop at the dose

Logging, reminders, and weigh-ins are part of the same flow, not separate tabs you have to remember to open.

Log

One tap to log

The dose, volume, and units you just drew are pre-filled. Confirm the injection site and any side-effect tags, and it's saved to your history.

Remind

Reminders per vial

Nettle sets your next-dose reminder automatically, scoped to that specific vial — so two active vials of the same peptide can run on independent schedules.

Weigh-in

Trends, not decisions

An optional weigh-in surfaces patterns worth bringing to your provider. Nettle never uses that data to suggest, adjust, or recommend a dose.

Nettle is a calculation, logging, and reference tool — not medical advice, and not a source for obtaining peptides. Tirzepatide is prescription-only in the U.S.; retatrutide and other library compounds are investigational and not FDA-approved. Always confirm doses and compound status with your prescriber or pharmacist. Read the full medical disclaimer.

Set up your first vial in under two minutes.

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