Injection temperature and peptide degradation

Rickcaps

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I've been debating the science behind the degradation of reconstituted peptide everytime it is put out of the refrigerator, and then it comes to room temp. for the pin. Few questions came to my mind,

1. If one uses the pens, everytime before pinning one will have to bring it to room temp, pin and then store it in a fridge again, what will be the degradation of the pep over 20 or 30 cycles?

2. What is the best way everyone uses to pin, get the vial to room temp. and then draw and pin?

Or

Just draw out of a cold vial and let the pin rest at room temp for an hour or so and then take it? That way the original peptide has very little exposure to temperature variations.
 
I draw from the vial, and let it come to temp in the pen.

That’s my chef mentality. If an item needs to stay cold then you take what you need, and keep the rest of the item in the environment it needs to be in.

It’s like taking a chicken breast out letting it come to room temperature, cutting it in half and then putting the other back half in the fridge. Lol.😂
 
I used to think like that, but I got to the point I don't think it really matters. If it sits out for a minute or an hour, it'll do it's job either way. I do think (therefore I don't know) bright light is the worst thing for it in a short period of time, compared to being room temperature.
 
I use a syringe but I draw cold and let it sit for about 5 minutes and then use it. I have never had any issues.
 
I think there is one pep that people complaining about burning more if it is cold (I don't remeber which), but for GLPs and most other peps, pinning cold should be just fine. Maybe you could get some discomfort if you were doing a really big dose, but I have never found it to be an issue.
 
If you have Mounjaro you will pin it cold , as advertised by the manufacturer.
If you use pens , you will use them from the fridge.
On aod and tesamorelin if you use a smaller gage needle it will go slower cold.
On ss31 also , it seems it likes to recrystallize if you use a smaller gage needle and less Bac water
 
I use syringes instead of pens, but I don't let the vial or syringe come to room temp before injecting.
 
1. If one uses the pens, everytime before pinning one will have to bring it to room temp, pin and then store it in a fridge again, what will be the degradation of the pep over 20 or 30 cycles?

2. What is the best way everyone uses to pin, get the vial to room temp. and then draw and pin?

Or

Just draw out of a cold vial and let the pin rest at room temp for an hour or so and then take it? That way the original peptide has very little exposure to temperature variations.
the degredation of letting it come to room temperature over 30 cycles is probably so minor you would never ever notice.
 
I've been debating the science behind the degradation of reconstituted peptide everytime it is put out of the refrigerator, and then it comes to room temp. for the pin. Few questions came to my mind,

1. If one uses the pens, everytime before pinning one will have to bring it to room temp, pin and then store it in a fridge again, what will be the degradation of the pep over 20 or 30 cycles?

2. What is the best way everyone uses to pin, get the vial to room temp. and then draw and pin?

Or

Just draw out of a cold vial and let the pin rest at room temp for an hour or so and then take it? That way the original peptide has very little exposure to temperature variations.
I take the pen/vial out, pin asap so it stay cool, and back in the fridge. I never let my 6 different peps warm up. Note that benzyl alcohol works better at room temp. I worry more about bacterial growth. Everything I have read say that peptides are quite robust below 80 degrees. You may loose 1% potency per month if you mishandle it => not much of an impact. My compounding pharma label indicated that 3 weeks at room temperature was fine for my glp1 (a great ++ when traveling). Avoid sun, no heat, just like Bac.
 
I used to let it adjust to room temperature and then decided I'd see what a cold pin felt like. I didn't notice any difference. So I only pin cold now. Maybe it makes a difference at higher mL amounts.
 
I've never even considered letting it warm up quite frankly. Draw and pin. Never noticed any kind of discomfort or unpleasantness from the cold.
 
For us its way more comfortable if it sits out & comes to room temp!! We tried without & noticed the difference. You could feel it vs not. This is in a pen w 32g 4mm tips
 
I wonder if the uncomfortable cold sensation is a function of needle length. With my 1/2" needle, I'm deeper into the fat, which has fewer nerves, and not the kind for feeling pain. With a short needle you're barely in the fat, just on the underside of the skin. Maybe you feel the cold sensation via your skin nerves.
 
I would assume that once drawn up into a very narrow insulin syringe the temperature would equilibrate with the environment quite quickly due to the high surface area to volume ratio. I have never waited to inject and never even noticed it feeling at all cold, and I would guess if it was still at fridge temperatures it would feel cold when injected at least to some degree.
 

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