{
  "$schema": "https://dosyne.com/api/v1/openapi.json",
  "endpoint": "https://dosyne.com/api/v1/syringes.json",
  "description": "Insulin syringe reference: what one mark is worth on each calibration, the barrel capacities those calibrations are sold in, and the conversion between scales.",
  "key_fact": "A syringe unit is a VOLUME defined by the barrel, never a quantity of drug. One U-100 unit is 0.01 mL of whatever the barrel contains.",
  "scales": [
    {
      "id": "U-100",
      "label": "U-100 insulin syringe",
      "units_per_ml": 100,
      "ml_per_unit": 0.01,
      "description": "One millilitre divided into 100 marks, so one unit is 0.01 mL. This is the scale every calculator on this site assumes and the scale almost all modern insulin syringes carry. A unit is a volume, not a quantity of drug.",
      "source": "https://dosyne.com/tools/insulin-syringe-visualizer/"
    },
    {
      "id": "U-40",
      "label": "U-40 insulin syringe",
      "units_per_ml": 40,
      "ml_per_unit": 0.025,
      "description": "One millilitre divided into 40 marks, so one unit is 0.025 mL — two and a half times the volume of a U-100 unit. Associated with some veterinary and older insulin products. Reading a U-40 barrel as though it were U-100, or the reverse, is a 2.5-fold volume error, not a rounding error.",
      "source": "https://dosyne.com/tools/insulin-syringe-visualizer/"
    },
    {
      "id": "tuberculin",
      "label": "Tuberculin (millilitre) syringe",
      "units_per_ml": 1,
      "ml_per_unit": 1,
      "description": "Marked in millilitres rather than insulin units, usually to 0.01 mL. It removes the unit conversion entirely — the calculated volume is read directly — but it does not remove the need to know the concentration.",
      "source": "https://dosyne.com/lab/how-to-reconstitute-peptides/"
    }
  ],
  "barrels": [
    {
      "capacity_ml": 0.3,
      "u100_capacity_units": 30,
      "graduation_note": "Sold with one-unit or half-unit lines depending on the product. The widest line spacing of the three, which is why a small volume is easiest to align here.",
      "scale": "U-100",
      "source": "https://dosyne.com/lab/read-an-insulin-syringe/"
    },
    {
      "capacity_ml": 0.5,
      "u100_capacity_units": 50,
      "graduation_note": "Commonly one-unit lines.",
      "scale": "U-100",
      "source": "https://dosyne.com/lab/read-an-insulin-syringe/"
    },
    {
      "capacity_ml": 1,
      "u100_capacity_units": 100,
      "graduation_note": "Often two-unit lines, though one-unit designs exist. Count the spaces between numbered marks on the device in hand rather than assuming every short line is one unit.",
      "scale": "U-100",
      "source": "https://dosyne.com/lab/read-an-insulin-syringe/"
    }
  ],
  "diluents": [
    {
      "id": "bacteriostatic-water",
      "name": "Bacteriostatic water for injection",
      "preservative": "benzyl alcohol, typically 0.9%",
      "multi_withdrawal": true,
      "note": "The preservative is what makes repeated withdrawals from one vial possible over a period of days. It is also why it is not used for every purpose: benzyl alcohol is contraindicated in neonates and some other settings.",
      "source": "https://dosyne.com/lab/bacteriostatic-water-for-peptides/"
    },
    {
      "id": "sterile-water",
      "name": "Sterile water for injection",
      "preservative": null,
      "multi_withdrawal": false,
      "note": "No preservative, so a vial reconstituted with it is a single-use preparation. Substituting one for the other changes how long the reconstituted vial can be used, not the arithmetic.",
      "source": "https://dosyne.com/lab/bacteriostatic-water-for-peptides/"
    }
  ],
  "provenance": "Compiled from the reference pages of dosyne.com, where the same values are stated in prose with the reasoning behind them. Every row carries the page it comes from.",
  "boundary": {
    "answers": [
      "Arithmetic: concentration, volume, syringe units, how many draws a vial holds.",
      "Instrument reference: what a mark on a given barrel is worth on a given scale.",
      "Procedure mechanics: what reconstitution does, what a diluent is, how storage affects a solution."
    ],
    "refuses": [
      "What compound anyone should use.",
      "What amount anyone should take, how often, or for how long.",
      "Whether a plan someone describes is safe, correct or advisable.",
      "Where to buy anything. This site names no vendor and links to none."
    ],
    "standing_caveats": [
      "A syringe reading is a volume. It says nothing about what is in the liquid.",
      "The arithmetic cannot verify the vial contains what the label claims, that it is sterile, or that its concentration is what was calculated.",
      "Most research peptides are not approved by the FDA or EMA for human use, and material sold for research use is not manufactured to pharmaceutical standards.",
      "Dosing decisions belong to a licensed prescriber."
    ]
  },
  "licence": {
    "name": "CC BY 4.0",
    "url": "https://creativecommons.org/licenses/by/4.0/",
    "attribution": "Dosyne — https://dosyne.com",
    "note": "Free to reuse, including commercially, with a link back to the page or endpoint it came from."
  }
}