I keep a written log of every draw with date, volume and syringe type.
I suspect the usual explanation for this is wrong, or at least incomplete.
I am aware this may have a boring answer. I would still like the boring answer stated clearly.
So what is the mechanism, and how well established is it?
Answer first: subcutaneous means into the fat layer beneath the dermis, and at the volumes discussed here the technique is forgiving as long as the needle is short and the site is pinched appropriately.
A 4 mm needle inserted at ninety degrees reaches subcutaneous tissue in essentially all adults without a skin fold. A 6 or 8 mm needle in a lean person may benefit from a lifted skin fold, or from a forty-five-degree angle.
| Vial | Diluent | Concentration | 0.25 mg | 0.5 mg | 1 mg | 2.5 mg |
|---|---|---|---|---|---|---|
| 5 mg | 1 mL | 5 mg/mL | 5 u | 10 u | 20 u | 50 u |
| 5 mg | 2 mL | 2.5 mg/mL | 10 u | 20 u | 40 u | 100 u |
| 10 mg | 1 mL | 10 mg/mL | 2.5 u | 5 u | 10 u | 25 u |
| 10 mg | 2 mL | 5 mg/mL | 5 u | 10 u | 20 u | 50 u |
| 10 mg | 3 mL | 3.33 mg/mL | 7.5 u | 15 u | 30 u | 75 u |
Units are U-100 insulin units, where 1 unit = 0.01 mL. Divide dose by concentration for millilitres, then multiply by 100.
Lipohypertrophy — a firm thickened area from repeated injection into the same spot — is the reason rotation matters. Injecting into it produces erratic and generally reduced absorption.
The caveat is that this describes technique, and research-use compounds are not approved for human use in any jurisdiction.
Abdomen, thigh or upper outer arm. Rotate within the region, two centimetres apart.
edited 28 Jun 2026 by rota_site — clarified the distinction between purity and content
HPLC purity, identity confirmation and quantified content on the vial you actually hold. Reports arrive with the chromatogram attached, not just a number.
Submit a sampleFounded 1998. ISO 9001 and cGMP certified, 1,500+ staff and 200+ patents. The synthesis house behind a great many of the vials that get sent out for testing - batch-specific documentation with every order.
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