COA_Karl said:Dead space is the answer to the missing dose.
I am going to disagree with reconstituting low as a general rule. More diluent, more punctures, more in-use days at room temperature, and the stability trade-off is real. Precision is not the only variable being optimised.
InsuranceTom said:I reconstituted a 10mg vial with 2ml of bacteriostatic water and I want someone to check my unit arithmetic before I draw anything, because I keep…
Ongoing cost tracking for dosing arithmetic — transparency for the community:
Monthly medication cost: $131
Supplies (syringes, BAC water, alcohol swabs): ~$9/month
Janoshik testing: ~$11/month (amortized quarterly)
Lab work: ~$51/month (amortized quarterly)
Total: ~$211/month
Compare to brand Wegovy at $1371/month without insurance. Compounded is roughly 90% cheaper for what I have found to be clinically equivalent medication.
PurityPaulOR said:I am going to disagree with reconstituting low as a general rule.
For anyone reconstituting dosing arithmetic peptides: the water-to-powder ratio determines your concentration. Here's my reference:
| Vial Size | BAC Water | Concentration | 0.25mg Dose |
|---|---|---|---|
| 5mg | 2mL | 2.5mg/mL | 10 units |
| 5mg | 2.5mL | 2mg/mL | 12.5 units |
| 10mg | 2mL | 5mg/mL | 5 units |
| 10mg | 3mL | 3.33mg/mL | 7.5 units |
More water = easier to measure small doses but vial runs out faster. Find the balance that works for your dose.
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Shop Reference StandardsA narrower follow-up, since the general answer is now clear:
How much material I am losing to dead space, and whether that explains why a 10mg vial gives me nine usable draws rather than ten?
Closing the loop on my own question.
Follow-up: it was dead space. Switching to a low-dead-space fixed-needle syringe gave me the tenth dose back.