Devices · Pens & autoinjectors · continued
Why a pen's dose steps are fixed and what that costs you — one year on posts 31–35
This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1 · go to the accepted answer.
The instruction leaflet for a licensed pen is a genuinely good technical document and is almost never read past the first page. It answers most of what gets asked here.
0 likes 11mo
preregistered, post #8: Dose counters: pens show the remaining number of doses. When the counter reaches zero, the pen is empty and cannot deliver more. Noting the counter before injection prevents running out unexpectedly. Go to post
Post #29 and I disagree about the size of the effect, not about the direction.
Where a device exists in more than one presentation, the instructions differ in small ways between them. Reading the leaflet that came with the one in your hand is the point.
The conclusion is tentative; the arithmetic underneath it is not.
Taking post #33 at face value and following it one step further.
Comparing cost per milligram between a pen and a vial ignores wastage, dead volume and the number of doses actually obtainable. Cost per delivered dose at your dose is the comparison that survives.
The step people skip is the one I have spelled out.
11 likes 11mo
This topic was referenced in
- A pen that felt like it delivered nothing: diagnosing it afterwardsDevices › Pens & autoinjectors · 39 replies
This topic was closed 120 days after the last reply. Closing is automatic for quiet topics so that a settled answer does not collect new questions underneath it. If you have a follow-up, open a new topic and link back to this one — that keeps both readable and gives your question its own title.
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