Injectable preparation safety
Solu-Cortef ACT-O-VIAL: the same volume can contain different doses
A two-milliliter package is not a dose. Solu-Cortef ACT-O-VIAL presentations can have different hydrocortisone strengths in the same reconstituted volume, so a preparation check must start with the actual vial.
Sources checked October 11, 2026. Independent educational content, not NABP exam questions or individual treatment advice.
Read strength and final volume together
The FDA label lists 100 mg and 250 mg ACT-O-VIAL presentations that each yield 2 mL when mixed. The resulting concentrations are 50 mg/mL and 125 mg/mL. Other ACT-O-VIAL sizes have their own stated final volumes.
A vial-size memory is not enough to choose a withdrawal volume. Read the hydrocortisone-equivalent amount and reconstituted volume on the actual presentation. The plain 100 mg vial is a different package and does not contain the diluent.
Calculate from the stated prepared product
For an order of 50 mg from a 100 mg/2 mL ACT-O-VIAL, 50 mg divided by 50 mg/mL gives 1 mL. From a 250 mg/2 mL ACT-O-VIAL, 50 mg divided by 125 mg/mL gives 0.4 mL. The milligram order has not changed; the concentration has.
Carry units through the calculation and verify the prepared product before withdrawing. This example is a volume check for a stated order, not a recommendation of a hydrocortisone dose for a particular disease or patient.
Follow the presentation-specific preparation steps
ACT-O-VIAL includes its own diluent compartment. The label describes activating it, mixing and then accessing the stopper under aseptic conditions. The supplied diluent is Water for Injection without preservative. The plain vial has separate preparation instructions.
Do not assume all hydrocortisone packages use the same diluent or final volume. The label distinguishes preparation for intravenous or intramuscular injection from further dilution for an infusion. The actual route and order must be verified rather than inferred from the presence of a vial.
Verify the dose, product and route before administration
The label expresses the strengths as hydrocortisone equivalents of hydrocortisone sodium succinate. A calculation should use the labeled hydrocortisone amount, not a molecular-weight conversion performed from the chemical name. Inspect the solution and follow the full product instructions.
Preparation errors can survive a correct arithmetic answer when the wrong package was selected. A complete check identifies the vial, mixes it as directed, confirms concentration, calculates volume and verifies the actual route. The worked case intentionally changes only the presentation to expose that failure.
A worked case
A 50 mg hydrocortisone order was previously prepared as 1 mL from a 100 mg ACT-O-VIAL. Today the available ACT-O-VIAL is 250 mg in 2 mL after mixing. Someone repeats the old 1 mL volume. What dose would that deliver, and what volume matches the stated order?
- The new concentration is 250 mg divided by 2 mL, or 125 mg/mL.
- One milliliter would contain 125 mg, not 50 mg.
- The stated 50 mg order requires 50 divided by 125, or 0.4 mL, after the product and order are verified.
Answer: Reusing the old volume gives the wrong dose. The presentation-specific volume for the stated order is 0.4 mL.
Try it before reading the answer
Write the key fact, decision and safety check first. These are original practice exercises, not recalled exam items.
1. Are the 100 mg and 250 mg ACT-O-VIAL concentrations the same?
No. Both yield 2 mL, with different drug amounts.
2. Does the plain 100 mg vial contain the ACT-O-VIAL diluent?
No.
3. Is the worked 50 mg order a disease-specific dose recommendation?
No. It is a preparation calculation for an explicitly stated order.
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Source dates and limits matter. Follow the current official source for clinical or regulatory decisions. Examples are simplified teaching cases, not prescribing, diagnostic or compounding instructions. Check the full current guidance and individual clinical context.