Protocol Cost Calculator

How this tool works · sources read September 30, 2026 · Grey Peptides Editorial Board

What the calculator computes

For each vial in your list the calculator works out how many doses the vial supplies, how many vials the protocol needs and what that costs at the price you enter. The arithmetic:

doses the vial contains = vial (mcg) ÷ dose (mcg), rounded down
doses in 28 days = doses per week × 4
doses per vial = the smaller of the two
vials needed = total doses ÷ doses per vial, rounded up
cost = vials needed × your price per vial, then divided by the weeks, days and months of the protocol

The supply list counts what the protocol uses: one insulin syringe per dose, one mixing syringe per vial, swabs for both, and bacteriostatic water at 2 mL per vial. It does not price them. The per-compound bars show where the weekly cost comes from.

Why no prices are filled in

Earlier versions pre-filled a price for every preset. Any such number is a seller's price, and a page that sells nothing and links to no seller should not be quoting one; the numbers also went stale the day they were typed. Enter what you actually pay. For approved GLP-1 medicines the manufacturers publish their own cash prices, and our GLP-1 transition planner lists them with the date they were read.

The 28-day limit, and why it changes the cost

An opened multiple-dose vial is dated when its stopper is first punctured and discarded within 28 days unless the manufacturer specifies otherwise.¹ Bacteriostatic water is the multiple-dose diluent this assumes; its preservative is 0.9% benzyl alcohol.² The calculator therefore never lets one vial supply more doses than 28 days of your schedule. For a daily compound the limit rarely matters. For a weekly one it dominates: a 5 mg vial of semaglutide holds twenty 0.25 mg doses, but 28 days of weekly dosing uses four, so the calculator counts four doses per vial and says so. Products mixed with sterile water and no preservative are single-use; EGRIFTA SV's label says to inject the dose at once and discard the rest.³

A worked example: an escalation, costed

Take the escalation steps on semaglutide's weight-management label, each held for four weeks,⁴ and a 5 mg multiple-dose vial mixed with bacteriostatic water. For each step the calculator compares what the vial contains with what 28 days of weekly doses use:

Counting milligrams alone, those 16 weeks use 13.8 mg, which looks like 3 vials. Counting what a vial can supply before its 28 days are up, they take 5. The difference is not arithmetic but discarded medicine: at the low doses most of each vial expires unused. Enter your own vial size and price and the calculator applies the same rule.

Where the presets come from

The presets are the same list the reconstitution calculator uses, with each dose's source: a drug label, a published trial, or a community amount labelled as one. For label and trial presets the schedule is the label's or the trial's (semaglutide and tirzepatide once weekly, tesamorelin and SS-31 once daily). For community presets no approved schedule exists, so the calculator starts at once a day as a placeholder, not a recommendation, and you should enter your own. The default list starts with one compound, semaglutide at its label starting dose, rather than a stack.

What it leaves out

Dose escalation. Approved GLP-1 medicines start low and step up every four weeks: semaglutide from 0.25 mg, tirzepatide from 2.5 mg, each increase only after at least four weeks.^5,6 A protocol that rises through three doses costs different amounts in each phase; enter each phase as its own line, or cost the phases separately.

What is really in the vial. The calculation trusts the label. When researchers bought semaglutide vials from illegal online pharmacies, the contents were 29% to 39% above the labelled amount and every vial contained bacterial endotoxin.⁷ A mislabelled vial changes the dose as well as the cost.

Waste. The count assumes every dose is drawn exactly and nothing is lost in the syringe, the stopper or a spilled vial.

Sources

1. The Joint Commission. Multi-dose vials: managing multi-dose vials of injectable medication (standards FAQ): an opened or accessed multiple-dose vial is dated and discarded within 28 days unless the manufacturer specifies a different date. Read September 30, 2026. Joint Commission
2. Hospira, Inc. Bacteriostatic Water for Injection, USP, prescribing information: 0.9% (9 mg/mL) benzyl alcohol as a bacteriostatic preservative; multiple-dose container; not for use in neonates. DailyMed version of July 8, 2026, read September 30, 2026.
3. Theratechnologies Inc. EGRIFTA SV (tesamorelin) for injection, US prescribing information: reconstitute with 0.5 mL Sterile Water for Injection; administer immediately and discard unused solution. DailyMed version of July 31, 2026, read September 30, 2026.
4. Novo Nordisk. WEGOVY (semaglutide) injection, US prescribing information: dose escalation 0.25 mg, 0.5 mg, 1 mg and 1.7 mg once weekly, each for 4 weeks, then 2.4 mg. DailyMed version of June 30, 2026, read September 30, 2026.
5. Novo Nordisk. OZEMPIC (semaglutide) injection, US prescribing information: initiate at 0.25 mg once weekly for 4 weeks, then escalate. DailyMed version of June 10, 2026, read September 30, 2026.
6. Eli Lilly and Company. MOUNJARO (tirzepatide) injection, US prescribing information: start at 2.5 mg once weekly for 4 weeks; increase in 2.5 mg steps after at least 4 weeks. DailyMed version of September 2, 2026, read September 30, 2026.
7. Ashraf, A. R. et al. (2024). Multifactor Quality and Safety Analysis of Semaglutide Products Sold by Online Sellers Without a Prescription: Market Surveillance, Content Analysis, and Product Purchase Evaluation Study. Journal of Medical Internet Research, 26, e65440. PMID: 39509151 · doi:10.2196/65440

This explainer describes how the tool works and what its numbers rest on. It is not medical advice and does not recommend any dose or product.