What HCG is
HCG is a glycoprotein hormone that acts at the luteinising hormone receptor. It is dosed in international units rather than milligrams, because it is a large glycosylated molecule whose activity is defined biologically rather than by mass.
How the pen is supplied
Solution in a sealed 3 ml pen graduated in 300 dial units. Supplying it pre-mixed removes the reconstitution step that HCG normally requires, which is the most common source of error with this compound.
Pen specification
| Class | Glycoprotein hormone, LH receptor agonist |
| Also known as | Human chorionic gonadotropin, Chorionic gonadotrophin |
| Content | 5000 iu |
| Fill volume | 3 ml |
| Dial graduation | 0.01 ml per unit |
| Total dial units | 300 |
| Per dial unit | 16.67 iu |
| Cost per iu | £0.01 per iu |
Milligrams per dial unit and cost per milligram are calculated from the pen strength, its fill volume and the current live price. Every SerenQ pen is graduated at 0.01 ml per unit.
Verification
Independent assay per batch, identifier printed on the pen.
- SerenQ HCG 5000iu Peptide Penout of stock£45
Availability checked 2026-09-04. The product page carries live stock.
Common questions
Why is HCG measured in iu rather than mg?
Because it is a large glycosylated hormone whose activity depends on more than its mass. International units express biological activity, which is the meaningful measure for this class.
Does the pen need reconstituting?
No. HCG normally ships as a lyophilised powder with a separate diluent, and mixing it is where most errors occur. The pen arrives as a made up solution.