Final Dose in the Pen?

WLBLD

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Once your 1st cartridge is nearly done and only a very small amount seems to remain, how can you tell whether it still holds your full dose, or what steps do you take to confirm it? A few times I ended up wasting some just to avoid air bubbles.

I began low with a 10mg 1ml bac cart. There should be around 2-3mg remaining, but it looks like almost nothing. I'm still on 1.5, so it's below that, yet I also don't want to miss out on a complete dose.
 
I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
 
Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
 
randompersonrandom said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Wow, that's a clever move.
Absolutely! My husband mentioned the price is reasonable, so he said to just toss whatever's left rather than risk a smaller dose. I figured someone in this community would know a smart approach 😊
 
WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
 
Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.
 
randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.
Yes, it is. And it works well for getting rid of that pesky last air bubble too.
 
randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
 
randompersonrandom said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
Honestly, I have no clue how you could have messed that one up.
 
Peotidethrowaway said:

randompersonrandom said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
Honestly, I have no clue how you could have messed that one up.
I really can't say. The only thing that comes to mind is that perhaps it mattered that the syringe wasn't inserted into the cart right in the middle — I was trying to avoid piercing the area where the pen needles attach — so the force during the push may have been a bit lopsided. Just speculation on my part, nothing more.
 
WLBLD said:

Once your 1st cartridge is nearly done and only a very small amount seems to remain, how can you tell whether it still holds your full dose, or what steps do you take to confirm it? A few times I ended up wasting some just to avoid air bubbles.

I began low with a 10mg 1ml bac cart. There should be around 2-3mg remaining, but it looks like almost nothing. I'm still on 1.5, so it's below that, yet I also don't want to miss out on a complete dose.
Check the dial and watch where it halts.

For example, if you set it to 20 units but it stops at 8, then you're missing 8 units.

If you're determined, you could draw up 8 units with an insulin syringe. Alternatively, just put in a fresh cartridge and inject 8 units from that (provided the concentration is the same).
 
randompersonrandom said:

Peotidethrowaway said:

randompersonrandom said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
Honestly, I have no clue how you could have messed that one up.
I really can't say. The only thing that comes to mind is that perhaps it mattered that the syringe wasn't inserted into the cart right in the middle — I was trying to avoid piercing the area where the pen needles attach — so the force during the push may have been a bit lopsided. Just speculation on my part, nothing more.
If I’ve got the wrong idea about your method, sorry — but my understanding is that you inserted the insulin syringe into the cartridge and, without applying any pressure to the syringe plunger, turned the dial on the pen to check whether the clicks would fill the syringe according to what the pen measured out? (As opposed to injecting anything into the cartridge while the pen plunger is still engaged.)

Sitting right at the edge of the rubber diaphragm really shouldn’t be an issue; that’s something I do routinely.
 
Labcat said:

randompersonrandom said:

Peotidethrowaway said:

randompersonrandom said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
Honestly, I have no clue how you could have messed that one up.
I really can't say. The only thing that comes to mind is that perhaps it mattered that the syringe wasn't inserted into the cart right in the middle — I was trying to avoid piercing the area where the pen needles attach — so the force during the push may have been a bit lopsided. Just speculation on my part, nothing more.
If I’ve got the wrong idea about your method, sorry — but my understanding is that you inserted the insulin syringe into the cartridge and, without applying any pressure to the syringe plunger, turned the dial on the pen to check whether the clicks would fill the syringe according to what the pen measured out? (As opposed to injecting anything into the cartridge while the pen plunger is still engaged.)

Sitting right at the edge of the rubber diaphragm really shouldn’t be an issue; that’s something I do routinely.

I

Grabbed the insulin syringe and, with the cap still on, worked the plunger back and forth a few times — I figured loosening it up a bit was harmless even if it likely wasn't needed — after which I pressed it down completely.

Set the pen to twenty clicks.

Put the syringe needle through the cartridge wall near its edge.

Pressed the pen down so it would inject.

Ended up with twenty units sitting in the syringe, told myself "yay", injected it, and when I later grabbed the pen again I could see fluid pooled at the base of the cartridge. I slid the cartridge out to look and saw the stopper had turned just barely crooked by then.

I cleaned the area inside the cartridge under the stopper, just to tidy it, reinserted the cartridge, attached a pen needle, and squandered a small number of units checking whether the stopper would straighten out again — it seemed to.

Then I carried on with what I had been doing.

I'm with you that this shouldn't have occurred, but occur it certainly did.
 
randompersonrandom said:

Labcat said:

randompersonrandom said:

Peotidethrowaway said:

randompersonrandom said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.

Update: well, I won't make that mistake again. The stopper rose crookedly, and a bit of SS31 escaped from the bottom. No real harm done—this cart only has a few days left—but if it had been a full cart of something long-lasting, I would have been furious.
Honestly, I have no clue how you could have messed that one up.
I really can't say. The only thing that comes to mind is that perhaps it mattered that the syringe wasn't inserted into the cart right in the middle — I was trying to avoid piercing the area where the pen needles attach — so the force during the push may have been a bit lopsided. Just speculation on my part, nothing more.
If I’ve got the wrong idea about your method, sorry — but my understanding is that you inserted the insulin syringe into the cartridge and, without applying any pressure to the syringe plunger, turned the dial on the pen to check whether the clicks would fill the syringe according to what the pen measured out? (As opposed to injecting anything into the cartridge while the pen plunger is still engaged.)

Sitting right at the edge of the rubber diaphragm really shouldn’t be an issue; that’s something I do routinely.

I

Grabbed the insulin syringe and, with the cap still on, worked the plunger back and forth a few times — I figured loosening it up a bit was harmless even if it likely wasn't needed — after which I pressed it down completely.

Set the pen to twenty clicks.

Put the syringe needle through the cartridge wall near its edge.

Pressed the pen down so it would inject.

Ended up with twenty units sitting in the syringe, told myself "yay", injected it, and when I later grabbed the pen again I could see fluid pooled at the base of the cartridge. I slid the cartridge out to look and saw the stopper had turned just barely crooked by then.

I cleaned the area inside the cartridge under the stopper, just to tidy it, reinserted the cartridge, attached a pen needle, and squandered a small number of units checking whether the stopper would straighten out again — it seemed to.

Then I carried on with what I had been doing.

I'm with you that this shouldn't have occurred, but occur it certainly did.
Often my stoppers sit a bit crooked, and the plastic plunger tends to drift off center without much effort. It could be that this particular stopper's cross section wasn't round enough, causing a leak—unrelated to your actions. I figure these items are no different from other goods: a few that ought to fail WC still wind up with us.
 
For those wondering, I reached the end of my cart. Took a close look and the cart holder was displaying the 20 line, so I assumed that would cover a 15 unit dose. Turns out I was mistaken. Fortunately the pen clued me in, since it refused to advance any further and indicated 3 units remained. Good thing I already had a fresh cart on hand and used it for the remainder. I wasn't aware the pen behaved this way. Really useful to know in case you come up short on a full dose!! Had no clue. Every day you pick up something new 🙂
 
WLBLD said:

For those wondering, I reached the end of my cart. Took a close look and the cart holder was displaying the 20 line, so I assumed that would cover a 15 unit dose. Turns out I was mistaken. Fortunately the pen clued me in, since it refused to advance any further and indicated 3 units remained. Good thing I already had a fresh cart on hand and used it for the remainder. I wasn't aware the pen behaved this way. Really useful to know in case you come up short on a full dose!! Had no clue. Every day you pick up something new 🙂
Right - each pen acts in its own way. Certain ones refuse to let you dial past a point; others simply halt at whatever number is left. In any case, these are useful traits, since they tell you what to do when you move to the next cartridge. As for the markings on the cartridge itself, they are well known for being unreliable.
 
randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.
Peptide Critic actually recommends this method for verifying pen accuracy, and that's how I found out my Amazon pen was a piece-o-junk.

I'll also confess that I went against the grain compared to what y'all do here. Rather than extracting the final small amount from the pen cartridge, I had a spare reconstituted vial of GHK-Cu ready, and I used a 3ml syringe to refill the cartridge directly in the pen...
 
deluge said:

randompersonrandom said:

Peotidethrowaway said:

WLBLD said:

Peotidethrowaway said:

I put an insulin needle into the pen cartridge and inject whatever remains of the pen dose into the needle so I can measure it
Thanks, that's a really clever approach. But is it able to push back afterward? I'm a fan of my tiny pen needles ha ha
That's possible, though it kind of defeats the point. Typically you're able to pull the remaining bit out of the cart as well. Once the plunger quits moving, there's still some left over.
Beyond that, it strikes me as a decent method for verifying whether your pens are delivering accurate units. You'd simply insert the syringe needle into the cart, dial, push, and then inspect. That beats the hassle of attaching a needle to the tip and forcing it into a syringe.
Peptide Critic actually recommends this method for verifying pen accuracy, and that's how I found out my Amazon pen was a piece-o-junk.

I'll also confess that I went against the grain compared to what y'all do here. Rather than extracting the final small amount from the pen cartridge, I had a spare reconstituted vial of GHK-Cu ready, and I used a 3ml syringe to refill the cartridge directly in the pen...
Once you depress the plunger, the cartridge is out in the open air and its sterility is gone. If you try to top it off by drawing the plunger back out, you're guaranteeing a cartridge that isn't sterile. I'd urge you not to do that at all.
 
ltjltj said:

WLBLD said:

For those wondering, I reached the end of my cart. Took a close look and the cart holder was displaying the 20 line, so I assumed that would cover a 15 unit dose. Turns out I was mistaken. Fortunately the pen clued me in, since it refused to advance any further and indicated 3 units remained. Good thing I already had a fresh cart on hand and used it for the remainder. I wasn't aware the pen behaved this way. Really useful to know in case you come up short on a full dose!! Had no clue. Every day you pick up something new 🙂
Right - each pen acts in its own way. Certain ones refuse to let you dial past a point; others simply halt at whatever number is left. In any case, these are useful traits, since they tell you what to do when you move to the next cartridge. As for the markings on the cartridge itself, they are well known for being unreliable.
It wasn’t clear to me at all until my 1st cart was done. Finding out it behaves that way was such a relief—now I don’t stress over whether I’m short a full dose. I can’t say every pen works like this, so it’s a big plus (especially as someone new, it felt good to have an actual signal, ha ha). I could tell it was close, which is exactly why I opened this thread to ask. I had zero idea 🙂

Are there pens out there that do neither—no # appearing afterward, and no block on dialing up?
 
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