hCG Dosing Chart

Start with the first table. Find the millilitres of diluent you actually added down the left, read across to the USP units printed on your vial, and the lower figure in the cell is what one mark on a U-100 insulin barrel carries. That single number is the one worth writing on the vial with a marker at the moment you mix it — everything else on this sheet can be recomputed from it.

IU and syringe marks are different quantities that share a word. An IU is hormone; a mark is one hundredth of a millilitre. At 1,000 IU/mL a 500 IU dose is 0.5 mL, which is 50 marks. Setting the plunger to 500 marks instead asks for 5 mL — five times what the largest insulin barrel holds. The third table prices that mistake at every reconstitution.

Both approved labels state intramuscular use only. The mark counts here are arithmetic and you may need them, but a fixed half-inch insulin needle does not give an intramuscular injection in most adults, and the instrument the labelled route calls for is a luer-lock barrel numbered in millilitres. Route is a prescriber’s decision, not a column on a chart.

Where the two labels differ, the last table prints both rather than picking one. They are different products with different diluents, and the figure that applies to you is the one on the carton in front of you.

Concentration and what one mark carries

Read down for the diluent you added, across for the USP units printed on your vial. The lower figure is what one mark on a U-100 insulin barrel carries.

The two rows marked "on the NOVAREL table" are reproduced here, not copied: NOVAREL's Table 1 prints 10,000 IU/mL and 5,000 IU/mL at 1 mL and 1,000 IU/mL and 500 IU/mL at 10 mL, and the computed cells above agree. PREGNYL tabulates no concentrations at all — it directs you to "remove 1 to 10 mL of solvent and add to vial with lyophilized powder" and ships a 10 mL solvent vial, so every row here is inside its directions. A volume outside 1–10 mL is described by neither label.

Marks to draw for a dose in IU

Read down for your dose in USP units, across for what you actually mixed. The large figure is marks on a U-100 insulin barrel; the volume is beneath it.

Greyed cells are over 1 mL and no insulin barrel takes them in one go — and that is the labelled instrument anyway, since both labels say intramuscular only and an intramuscular injection is given from a luer-lock barrel numbered in millilitres. Note what the columns do and do not change: the dose is identical across a row. More diluent makes the mark bigger and easier to read; it does not change how much hormone you are giving.

Reading IU as marks — what 500 IU costs at each reconstitution

The failure this sheet exists to stop, priced. Every row is the same 500 IU dose; the only thing that changes is how much diluent went into the vial.

The last column is the finding, and it is not a lookup: the overdose factor IS the IU-per-mark figure in the first column, because both are the concentration divided by the same 100. The third column is the one that does not move — 500 marks is 5 mL at every concentration on this sheet, because a mark is a volume. So the harm scales with how densely you mixed the vial and the rescue does not. What stops this particular mistake is only that 5 mL exceeds every insulin barrel, and that is true only because 500 is greater than 100. A dose of 100 IU or less misread as marks draws under 1 mL and passes without a murmur.

Whole doses per vial, and what is stranded

Diluent volume does not appear in this table on purpose: diluting further does not create more hormone.

Part doses are not counted. How many of these you actually get through is capped by the refrigerated shelf life, and the two labels differ — 60 days for PREGNYL, 30 for NOVAREL. NOVAREL frames the same choice in its own table: the 1 mL reconstitution is to "Administer entire dose at once" and the 10 mL one is for "Multiple dose administration, refrigerate between doses".

PREGNYL against NOVAREL — where the two approved labels differ

Two licensed biologics, the same hormone, different documents. Where they disagree both figures are printed and neither is averaged away.

Sixty days and thirty days are both correct, each for its own product with its own diluent, and this sheet does not average them or choose between them. The same applies to vial strength: a "5,000 or 10,000 IU vial" is a fact about NOVAREL, not about hCG — PREGNYL’s HOW SUPPLIED lists a single 10,000 USP unit vial. Read the carton you actually have.

Frequently asked questions

How many syringe units is 500 IU of hCG?

It depends entirely on how much diluent went into the vial, and the question contains the trap. Reconstitute a 10,000 IU vial with 10 mL and you have 1,000 IU/mL, so 500 IU is 0.5 mL — 50 marks. Reconstitute the same vial with 1 mL and you have 10,000 IU/mL, so 500 IU is 0.05 mL — 5 marks. Both reconstitutions are printed on NOVAREL’s own label. What 500 IU never is, at any concentration, is 500 marks: that is 5 mL, five times what the largest insulin barrel holds.

How much bacteriostatic water do I add to a 10,000 IU hCG vial?

NOVAREL’s Table 1 gives two volumes and says what each is for: 1 mL produces 10,000 IU/mL and is to "Administer entire dose at once"; 10 mL produces 1,000 IU/mL and is for "Multiple dose administration, refrigerate between doses". PREGNYL tabulates nothing and instead directs you to "remove 1 to 10 mL of solvent and add to vial with lyophilized powder", shipping a 10 mL solvent vial. Inside that range the trade-off is readability: at 1,000 IU/mL one mark carries 10 IU, at 10,000 IU/mL one mark carries 100 IU, so a quarter-mark misjudgement costs ten times as much at the denser mix.

How long does reconstituted hCG last in the fridge?

The two approved labels disagree and both are correct for their own product. PREGNYL: "IF NEEDED, THE RECONSTITUTED SOLUTION IS STABLE FOR 60 DAYS WHEN REFRIGERATED. DO NOT FREEZE. USE THE RECONSTITUTED SOLUTION WITHIN 60 DAYS OF RECONSTITUTION." NOVAREL: "REFRIGERATE RECONSTITUTED PRODUCT AT 2° to 8°C (36° to 46°F) AND USE WITHIN 30 DAYS." They ship different diluents — PREGNYL its own buffered solvent with 0.9% benzyl alcohol, NOVAREL a 10 mL vial of Bacteriostatic Water for Injection with 0.9% benzyl alcohol — so the two figures are not interchangeable. Averaging them to 45 days would invent a number neither label supports. Date the vial when you mix it and use the number on your own carton.

Can hCG be injected subcutaneously with an insulin syringe?

Not per either label. PREGNYL opens its dosage section "For intramuscular use only. Each multiple-dose vial is to be used for one patient." NOVAREL heads its own "(Intramuscular Use Only)". Subcutaneous hCG drawn on an insulin barrel is widespread in men’s health practice and is not the labelled route for either approved product — that is a difference between practice and labelling, and this sheet will not present one as the other. Mechanically it matters too: an insulin syringe carries a fixed needle of roughly 6 to 12.7 mm, which will not reach muscle in most adults even when an intramuscular injection was what you intended.

What dose of hCG do the labels state for men?

Both give two alternatives for the male indication and introduce them with a caveat worth reading first: "The following regimens have been advocated by various authorities." The first is 500 to 1,000 USP units three times a week for three weeks, followed by the same dose twice a week for three weeks. The second is 4,000 USP units three times weekly for six to nine months, after which the dosage may be reduced to 2,000 USP units three times weekly for a further three months. That is label text for one approved diagnosis — selected cases of hypogonadotropic hypogonadism — not a recommendation from this sheet, and not a protocol for using hCG alongside testosterone, which is not a labelled indication for either product.

Why is 500 IU fifty marks and not five hundred?

Because the two numbers count different things. An IU is a quantity of hormone; a mark on a U-100 barrel is a quantity of volume — one hundredth of a millilitre, by the definition of the U-100 scale and nothing else. At 1,000 IU/mL one mark carries 10 IU, so 500 IU needs 50 of them. Someone who sets the plunger to 500 marks has not misread a scale and has not made an arithmetic slip — they have used the right number against the wrong quantity, and it costs exactly the IU-per-mark figure: 10× the dose at this concentration and 100× at 10,000 IU/mL.

Does adding more diluent make an hCG vial last longer?

No. A 10,000 IU vial holds 10,000 IU whether you reconstitute it with 1 mL or 10 mL, so at 500 IU a dose it contains 20 doses either way — which is why the doses-per-vial table on this sheet has no diluent axis at all. What changes is the size of the draw: at 10,000 IU/mL that dose is 5 marks and at 1,000 IU/mL it is 50. More diluent buys a bigger, easier-to-read mark, not more hormone. The real cap on how many doses you get through is the refrigerated shelf life on your own carton — 60 days for PREGNYL, 30 for NOVAREL.

Do the quarter marks on this chart exist on my syringe?

No, and that is worth knowing before you lean on one. Mark counts here are rounded to the quarter because that is the finest split anyone can reasonably eyeball between two printed lines — it is not a claim that a quarter mark is printed on your barrel. We could not source the graduation interval of a 0.5 mL or 1 mL insulin barrel from any manufacturer instruction-for-use or FDA device listing, which is why /charts/insulin-syringe-conversion-chart prints "Not documented" in that column and this sheet agrees with it. The only sub-unit scale any manufacturer states is embecta’s: "½ unit scale marking available on the 0.3mL barrel". If a dose on this sheet turns on a quarter-mark difference, mix the vial thinner so the same dose lands on a bigger number.

Sources

1. [1]FDA label — PREGNYL (chorionic gonadotropin) for injection, Organon LLC. DailyMed SPL 1e94155f-19be-4944-b197-be4edbb4faf9, approval block BLA 017692, SPL version 11, effective 2025-12-02. Source of “Selected cases of hypogonadotropic hypogonadism (hypogonadism secondary to a pituitary deficiency) in males.”, “For intramuscular use only. Each multiple-dose vial is to be used for one patient.”, “Remove 1 to 10 mL of solvent and add to vial with lyophilized powder; agitate gently until powder is completely dissolved in solution. Do not shake.”, “IF NEEDED, THE RECONSTITUTED SOLUTION IS STABLE FOR 60 DAYS WHEN REFRIGERATED. DO NOT FREEZE. USE THE RECONSTITUTED SOLUTION WITHIN 60 DAYS OF RECONSTITUTION.”, the single 10,000 USP unit vial presentation and the two male regimens
2. [2]FDA label — NOVAREL (chorionic gonadotropin) for injection, for intramuscular use, Ferring Pharmaceuticals Inc. DailyMed SPL ac6918ff-9dc3-40d9-8619-54b26e4bdfc8, approval block BLA 017016, SPL version 41, effective 2025-08-27. Source of Table 1 “Final Concentration after Reconstitution” (1 mL → 10,000 IU/mL and 5,000 IU/mL, “Administer entire dose at once”; 10 mL → 1,000 IU/mL and 500 IU/mL, “Multiple dose administration, refrigerate between doses”), the “(Intramuscular Use Only)” dosage heading, “The following regimens have been advocated by various authorities.”, the 5,000 and 10,000 USP unit presentations and “REFRIGERATE RECONSTITUTED PRODUCT AT 2° to 8°C (36° to 46°F) AND USE WITHIN 30 DAYS.”
3. [3]FDA label — Bacteriostatic Water for Injection, USP, Hospira Inc. DailyMed SPL 87d6e9dc-fe3b-4593-ac9a-d7493d1959c7. The diluent NOVAREL supplies: a sterile, nonpyrogenic preparation of water for injection containing 0.9% (9 mg/mL) or 1.1% (11 mg/mL) of benzyl alcohol added as a bacteriostatic preservative
4. [4]embecta (formerly BD Diabetes Care) — Ultra-Fine insulin syringes. Barrel capacities and the only sub-unit scale any manufacturer states: “Designed with large dose unit markings, with ½ unit scale marking available on the 0.3mL barrel.”