Questions on peptide pens, dosing, and temperature shifts

[DJ _Yus]

I've done some reading, but I'm still unsure what the best approach is for my weekly injection, which comes from a pen I keep in the fridge in between doses.

According to some, you should allow the reconstituted pep to reach room temperature before injecting.

Others argue that the pep should stay out of the fridge for as short a time as possible, since temperature swings speed up biodegradation. That would mean injecting quickly once you remove the pep from the fridge.

What are your thoughts, and what do you do?

 

[SeaGypsy]

My pens never sit out — I take them out of the fridge, use them, and they go right back in. Repeated warming and cooling is probably harmful to the peptide. If bringing it to room temperature feels necessary, skip the pen: draw your dose from the vial instead, then return the vial to the fridge.

 

[desinr-gal]

SeaGypsy said:

My pens never sit out — I take them out of the fridge, use them, and they go right back in. Repeated warming and cooling is probably harmful to the peptide. If bringing it to room temperature feels necessary, skip the pen: draw your dose from the vial instead, then return the vial to the fridge.

I'm on the same page here. Temperature swings don't cause me any trouble, and my supply stays good for months. It's the repeated warming and cooling, from what I've read, that can break peptides down.

 

[Grogu]

SeaGypsy said:

My pens never sit out — I take them out of the fridge, use them, and they go right back in. Repeated warming and cooling is probably harmful to the peptide. If bringing it to room temperature feels necessary, skip the pen: draw your dose from the vial instead, then return the vial to the fridge.

That all makes sense to me, though I'd tack on one point: certain peptides hurt less when they're at room temperature, and if that's the case for yours, then your recommended method is the way to go.

As far as I can tell, the sole "upsides" of loading a weekly peptide into a pen come down to two things. First, you're able to push out the leftover air from the cartridge — for whatever reason, I get a real kick out of that. Second, you avoid piercing a vial, since pen needles are extremely sharp. I always assumed a single stab through a vial stopper wouldn't blunt a needle, but it turns out it does. Beyond that, using pens for weekly shots barely saves any time at all.

 

[desinr-gal]

Grogu said:


I agree with all of this, but just add that some peptides cause less pain at room temperature and in those cases what you suggest is the best approach.

The only "benefits" I can see of putting a weekly peptide in a pen is the fact that you can expel the extra air from the cartridge. I really like that for some reason. And also not puncturing a vial, pen needles are super sharp. I never thought that just one puncture of a vial stopper would dull a needle, but yup, it does. Otherwise, pens for weekly injections only speed things up by a fraction.

Click to expand...

If one vial is being used across an extended stretch, that can cut down on both time and plastic usage. With my 30mg vials, I get 30 pins at 1mg per pin, taken every 4 days, so the supply stretches over 4 months.

On top of that, pen needles are a clear improvement.

 

[SeaGypsy]

Grogu said:


I agree with all of this, but just add that some peptides cause less pain at room temperature and in those cases what you suggest is the best approach.

The only "benefits" I can see of putting a weekly peptide in a pen is the fact that you can expel the extra air from the cartridge. I really like that for some reason. And also not puncturing a vial, pen needles are super sharp. I never thought that just one puncture of a vial stopper would dull a needle, but yup, it does. Otherwise, pens for weekly injections only speed things up by a fraction.

Click to expand...

Absolutely — that's a big part of why pen needles win for me: they stay sharp and glide in easily. Most of the time I don't even notice the injection going in.

 

[eidos]

You're going to receive just as many opinions as this forum has members.



Looking at it through physical chemistry:

• During reconstitution, the water doesn't undergo a phase change (solid to liquid). So the solutes aren't subjected to any physical stress.
  
• In reaction equations, temperature is expressed in Kelvin (keeping it simple ), so moving from 2°C to 25°C is the same as moving from 275K to 298K. That works out to under a 10% shift in temperature.
  
• GLP-1s contain a large number of hydrogen bonds and hydrophobic interactions, which means that within this temperature range, the energy change (ΔG) stays under 10%.
  
• Rising temperature boosts solubility and will dissociate some hydrophobic aggregates (don't waste time looking: they're invisible to the naked eye; if you can see them, your solution has gone bad).
  
• At typical reconstitution concentrations, adsorption onto glass walls is negligible (roughly 1 per thousand), so it doesn't play a role in our scenarios.

Broadly speaking, steer clear of temperatures beyond 25°C. Notable degradation takes place above 30°C (deamidations, faster oxidation).

You don't have to let it reach room temperature. Around 15°C is a fine stopping point (cases with built-in thermometers are easy to find). That's sufficient to raise solubility and avoid thermal shock, which some white blood cells dislike (some individuals are allergic to cold...).

So warming it up is acceptable, and though it isn't required, it gives a small benefit.

 

[Grogu]

SeaGypsy said:


Yes, that's one of the reasons I love the pen needles, always sharp and smooth. I rarely ever feel one during the sick.

Click to expand...

Absolutely, that's a great perk of pen needles as well. They glide in effortlessly. I never would have guessed that a single poke could blunt an insulin needle so significantly, yet it truly does.

 

[desinr-gal]

eidos said:

You're going to receive just as many opinions as this forum has members.



Looking at it through physical chemistry:

• During reconstitution, the water doesn't undergo a phase change (solid to liquid). So the solutes aren't subjected to any physical stress.
  
• In reaction equations, temperature is expressed in Kelvin (keeping it simple ), so moving from 2°C to 25°C is the same as moving from 275K to 298K. That works out to under a 10% shift in temperature.
  
• GLP-1s contain a large number of hydrogen bonds and hydrophobic interactions, which means that within this temperature range, the energy change (ΔG) stays under 10%.
  
• Rising temperature boosts solubility and will dissociate some hydrophobic aggregates (don't waste time looking: they're invisible to the naked eye; if you can see them, your solution has gone bad).
  
• At typical reconstitution concentrations, adsorption onto glass walls is negligible (roughly 1 per thousand), so it doesn't play a role in our scenarios.

Broadly speaking, steer clear of temperatures beyond 25°C. Notable degradation takes place above 30°C (deamidations, faster oxidation).

You don't have to let it reach room temperature. Around 15°C is a fine stopping point (cases with built-in thermometers are easy to find). That's sufficient to raise solubility and avoid thermal shock, which some white blood cells dislike (some individuals are allergic to cold...).

So warming it up is acceptable, and though it isn't required, it gives a small benefit.

It's summertime. 25C is the same as 77 degrees fahrenheit. Around where I am, it's roughly 83 degrees right now and will climb to 90 eventually, so.. I suppose it comes down to your location.

Mine won't be brought up to room temp.

 

[eidos]

desinr-gal said:

eidos said:

You're going to receive just as many opinions as this forum has members.



Looking at it through physical chemistry:

• During reconstitution, the water doesn't undergo a phase change (solid to liquid). So the solutes aren't subjected to any physical stress.
  
• In reaction equations, temperature is expressed in Kelvin (keeping it simple ), so moving from 2°C to 25°C is the same as moving from 275K to 298K. That works out to under a 10% shift in temperature.
  
• GLP-1s contain a large number of hydrogen bonds and hydrophobic interactions, which means that within this temperature range, the energy change (ΔG) stays under 10%.
  
• Rising temperature boosts solubility and will dissociate some hydrophobic aggregates (don't waste time looking: they're invisible to the naked eye; if you can see them, your solution has gone bad).
  
• At typical reconstitution concentrations, adsorption onto glass walls is negligible (roughly 1 per thousand), so it doesn't play a role in our scenarios.

Broadly speaking, steer clear of temperatures beyond 25°C. Notable degradation takes place above 30°C (deamidations, faster oxidation).

You don't have to let it reach room temperature. Around 15°C is a fine stopping point (cases with built-in thermometers are easy to find). That's sufficient to raise solubility and avoid thermal shock, which some white blood cells dislike (some individuals are allergic to cold...).

So warming it up is acceptable, and though it isn't required, it gives a small benefit.

It's summertime. 25C is the same as 77 degrees fahrenheit. Around where I am, it's roughly 83 degrees right now and will climb to 90 eventually, so.. I suppose it comes down to your location.

Mine won't be brought up to room temp.

In southwestern France today it got even hotter: 97°F/36°C. And that wasn't even the hottest day of the month!

So my suggestion was that you don't have to wait for it to reach “room temperature.” Better to watch what's actually happening.

 

[desinr-gal]

eidos said:

desinr-gal said:

eidos said:

You're going to receive just as many opinions as this forum has members.



Looking at it through physical chemistry:

• During reconstitution, the water doesn't undergo a phase change (solid to liquid). So the solutes aren't subjected to any physical stress.
  
• In reaction equations, temperature is expressed in Kelvin (keeping it simple ), so moving from 2°C to 25°C is the same as moving from 275K to 298K. That works out to under a 10% shift in temperature.
  
• GLP-1s contain a large number of hydrogen bonds and hydrophobic interactions, which means that within this temperature range, the energy change (ΔG) stays under 10%.
  
• Rising temperature boosts solubility and will dissociate some hydrophobic aggregates (don't waste time looking: they're invisible to the naked eye; if you can see them, your solution has gone bad).
  
• At typical reconstitution concentrations, adsorption onto glass walls is negligible (roughly 1 per thousand), so it doesn't play a role in our scenarios.

Broadly speaking, steer clear of temperatures beyond 25°C. Notable degradation takes place above 30°C (deamidations, faster oxidation).

You don't have to let it reach room temperature. Around 15°C is a fine stopping point (cases with built-in thermometers are easy to find). That's sufficient to raise solubility and avoid thermal shock, which some white blood cells dislike (some individuals are allergic to cold...).

So warming it up is acceptable, and though it isn't required, it gives a small benefit.

It's summertime. 25C is the same as 77 degrees fahrenheit. Around where I am, it's roughly 83 degrees right now and will climb to 90 eventually, so.. I suppose it comes down to your location.

Mine won't be brought up to room temp.

In southwestern France today it got even hotter: 97°F/36°C. And that wasn't even the hottest day of the month!

So my suggestion was that you don't have to wait for it to reach “room temperature.” Better to watch what's actually happening.

Oh no! Which part of southwestern France are you in? I'll be over there toward the end of summer — what kind of temperatures should I expect and plan for?

 

[BNLFL]

SeaGypsy said:


Yes, that's one of the reasons I love the pen needles, always sharp and smooth. I rarely ever feel one during the stick.

Click to expand...

For 1 month, your pen is being confiscated, and in its place you'll get syringes fitted with 23g 1.5" needles.

 

[SeaGypsy]

BNLFL said:


We're taking away your pen for a month and giving you syringes with 23g 1.5" needles.

Click to expand...

But whhhyyyyy what did I do to deserve this? Sorry in advance — flowers Don’t confiscate my pens, please!!!!

 

[Rezwalker]

straight out of the refrigerator, into the pin

that chilly rush in the glutes first thing in the morning

the finest possible way to kick off a brand new day!

 

[eidos]

desinr-gal said:

eidos said:

desinr-gal said:

eidos said:

You're going to receive just as many opinions as this forum has members.



Looking at it through physical chemistry:

• During reconstitution, the water doesn't undergo a phase change (solid to liquid). So the solutes aren't subjected to any physical stress.
  
• In reaction equations, temperature is expressed in Kelvin (keeping it simple ), so moving from 2°C to 25°C is the same as moving from 275K to 298K. That works out to under a 10% shift in temperature.
  
• GLP-1s contain a large number of hydrogen bonds and hydrophobic interactions, which means that within this temperature range, the energy change (ΔG) stays under 10%.
  
• Rising temperature boosts solubility and will dissociate some hydrophobic aggregates (don't waste time looking: they're invisible to the naked eye; if you can see them, your solution has gone bad).
  
• At typical reconstitution concentrations, adsorption onto glass walls is negligible (roughly 1 per thousand), so it doesn't play a role in our scenarios.

Broadly speaking, steer clear of temperatures beyond 25°C. Notable degradation takes place above 30°C (deamidations, faster oxidation).

You don't have to let it reach room temperature. Around 15°C is a fine stopping point (cases with built-in thermometers are easy to find). That's sufficient to raise solubility and avoid thermal shock, which some white blood cells dislike (some individuals are allergic to cold...).

So warming it up is acceptable, and though it isn't required, it gives a small benefit.

It's summertime. 25C is the same as 77 degrees fahrenheit. Around where I am, it's roughly 83 degrees right now and will climb to 90 eventually, so.. I suppose it comes down to your location.

Mine won't be brought up to room temp.

In southwestern France today it got even hotter: 97°F/36°C. And that wasn't even the hottest day of the month!

So my suggestion was that you don't have to wait for it to reach “room temperature.” Better to watch what's actually happening.

Oh no! Which part of southwestern France are you in? I'll be over there toward the end of summer — what kind of temperatures should I expect and plan for?

Send me a direct message instead — there's too much detail for me to put out in the open.

 

[Commander]

I inject straight out of the fridge. In my view, the chance of damaging the peptide isn't worth taking. Should cold injections bother you, skip the pen altogether. Grab an insulin syringe, pull your dose, then leave that syringe out until it reaches room temperature.

If a pen's convenience is what you're after, then cold injections are simply part of the deal…

 

[BNLFL]

Commander said:

I inject straight out of the fridge. In my view, the chance of damaging the peptide isn't worth taking. Should cold injections bother you, skip the pen altogether. Grab an insulin syringe, pull your dose, then leave that syringe out until it reaches room temperature.

If a pen's convenience is what you're after, then cold injections are simply part of the deal…

There's no way you'll damage it.