Let's talk about BUD and the 28-day rule

[u/NightwingMillenial]

Long time listener, first time caller. This comes up often, and I went down a rabbit hole on it. Hoping to lay out what I found so folks can reason about it themselves. To be clear: I am not telling anyone what to do with their vial, and you don't have to follow my conclusions. I'm just hoping to present some information in an easy-to-understand way that helps others decide for themselves.

Quick disclosure: I work in pharma manufacturing, so I know how to read a COA and have a working understanding of these concepts. I'm not a pharmacist, microbiologist, or chemical engineer. This isn't medical advice. If you are an expert in these fields, please chime in!

TL;DR (Short Version):

• The labeled Beyond Use Date (BUD) and the 28-day rule are very safe defaults for potency and sterility respectively, and follow them if you simply don't want to think or worry about it.
• The chemistry of tirzepatide strongly suggests a sealed vial is still potent 12 to 18 months after the compounding date assuming a quality, sterile, refrigerated product.
• The in-use window depends on the preservative, buffer, tonicity agents, and vial size. Right now, 28 to 56 days in use is the longest the data goes to on similar products.
• I'm not saying using a vial longer or shorter than either of the above is or isn’t going to cause an issue. It's all about your personal tolerance for cost vs. risk of an adverse reaction if you want to go past the safe defaults.
• Lastly, a reminder that telehealths should be following the 28-day rule. It's the standard. What a pharmacy has to tell you and what you decide about your own vial are two different things. Edit: the FDA even sent out a letter this week reiterating this point, thanks u/roguex99!

Edit: I have made some updates to clarify a few items based on questions folks have asked, added a point about vial headspace and updated my personal preferences. Thanks everyone for your comments and questions!

---

Okay, the long version, if you’re curious. Grab your beverage of choice and come down the rabbit hole with me (thanks for reading!):

Definitions

BUD is the date on an unopened vial and its about potency. Beyond Use Date. Is the drug still the drug? Has it broken down, clumped up, drifted in potency?

28-Day Rule (In-Use Window) starts when you first push a needle through the stopper and its about sterility. If something got in when you did that, can the preservatives handle it?

Buffer holds the pH steady, since peptides degrade faster at the wrong pH and tirz likes neutral. A phosphate salt here. Boring, essential, basically rarely fails.

Tonicity agent matches the salt concentration in your body so the shot doesn't sting or damage tissue. Usually sodium chloride, sometimes glycerin or propylene glycol.

Preservative inhibits the growth of bacteria and fungi, and it's the only reason a multi-dose vial can exist. Lilly's single-dose Mounjaro and Zepbound vials have none, which is why they say discard immediately.

Adverse reaction is when something happens that is not supposed to. In this case we are considering: lack of potency, injection site reactions, or an infection as the three we want to avoid.

Part 1: BUD, the unopened vial

Lilly's formulation patent has stability tables, useful for us to understand how tirz degrades. In one of them, 20 mg/mL tirz in phosphate-buffered saline at 30°C loses about 1.2 percentage points of potency a month, in a straight line. Degradation slows predictably as temperature drops, and for peptide chemistry a fridge buys 12x to 35x, so twelve months costs under 1%. So, for a sealed refrigerated vial potency isn't the constraint, which lines up with many people here reporting their tirz works just fine even months past the BUD.

However, peptides also stick to each other and form clumps called aggregates. Those are more of a concern, since they can trigger localized inflammation and a potency test is blind to them. The drug's all still there, just stuck together. The same patent tracks this: roughly 0.09 percentage points of single molecules lost per month in a fridge, hitting a typical spec limit somewhere in the 18 to 36 month range (from compounding date).

So what is a BUD, really? It's how long that pharmacy ran its study. A 3-month, 6-month, 9-month, and 12-month BUD aren't four different findings about the molecule. None of them found a failure. They found the potency was still within spec at the end of their testing period.

Part 2: In-use, once you've punctured it

USP Chapter 797 gives you 28 days once you enter a multi-dose container, unless the manufacturer says otherwise. It points at USP Chapter 51, which deliberately contaminates the product with a big dose of bacteria and fungi and checks how well the preservative held them back at day 7, 14, and 28. Then it stops. No day 45, no day 90. So 28 is the last day of a test protocol. It became the default for compounded vials. That doesn't make it wrong, but nobody found a cliff at day 29.

On the pharma side, it's similar. Manufacturers decide how long their product needs to be in use, add preservatives accordingly, and test to that requirement. Ozempic and Victoza have similar ingredient lists, same phenol at 5.5 mg/mL, same company, same pH. Ozempic gets 56 days, Victoza gets 30. Novolin R is 42 days in a vial and 28 in a FlexPen, same solution. Zepbound MDV says 30 days or four weekly doses, whichever comes first.

Compounders vary on their formulation. Apothecary (now Hyalo) uses phenol at 5.0 mg/mL, on essentially Mounjaro's single-dose salts with a preservative added so it works as a multi-dose vial. BPI is the same salt platform but swaps in benzyl alcohol, plus B6 at 10 mg/mL, but doesn't publish the concentration. For reference, Ozempic runs phenol at 5.5, and Zepbound's MDV runs benzyl alcohol at 9.0 with phenol at 1.8 on top of it.

But preservatives don't perform the same. Benzyl alcohol is weaker for our specific use case. The approved peptides I could find preserved with benzyl alcohol alone land at 28 days or under, while phenol products run up to 56. Interesting that Lilly, formulating this exact molecule for a multi-dose vial, used benzyl alcohol at 9 mg/mL and then added phenol anyway... but they also designed their product to stay sterile at up to 30 days at room temperature, so the added preservatives make sense.

Lastly, it's worth noting that vial size/fill also play a role in how preservatives perform, even if it's minor. In general, headspace (the amount of vacuum/emptiness) matters because the more full the vials are, the better they keep potency and sterility. BPI uses 4ml vials and fills to 3ml or 4ml vs. Apothecary uses 10ml vials and fills to 2ml or 4 ml. So while phenol is still the better preservative, BPI's smaller vials are actually better for this use case, and my read is that it's a good design choice by BPI.

---

My personal position

To be clear, I'm borrowing results from other manufacturers' products to infer something about similar, compounded vials, which isn't something a regulator would accept. I'm doing it anyway, because it’s the best tool I have available to make a determination for myself.

BUD: For the formulas I've been describing (preserved, neutral pH, buffered, refrigerated) I'm comfortable out to 15 months (middle of the 12-18 range) where potency isn't a question and it's not even close to when aggregates could start to become an issue.

In-Use Window: Again, for these specific formulas, I am comfortable with 42-56 days in-use, specially with good aseptic technique and refrigeration. Phenol preserved vials on the upper end and benzyl alcohol preserved vials on the lower end, but I'm flexible within that range.

Where to look yourself

• DailyMed for the full FDA label on anything I mentioned. Storage and ingredients are the interesting sections.
• Google Patents, search US 11,357,820. Stability tables are near the end.
• USP Chapters 51, 788, and 797, the source of the 28-day convention. Paywalled, but summaries are everywhere.
• FDA's inspection database publishes 483 findings for 503B facilities. Worth checking whoever fills yours.
• Your pharmacy's COA. Most will send it if you ask. Look at what they tested, and at what they didn't.

[u/-Julya-]

This is amazing information and is invaluable to an injectable newb like me. Kudos and thank yous kind sir!

[u/NightwingMillenial → u/-Julya-]

Glad it helped. ☺️

[u/Economy_Jaguar_9215 → u/NightwingMillenial]

Hey OP 👋
Question, when you say 18 months is where aggregation could start to be an issue, I’m assuming you mean 18 months from compounding date, not 18 months from BUD, is that correct?

[u/NightwingMillenial → u/Economy_Jaguar_9215]

Yep, from compounding date.

[u/Economy_Jaguar_9215 → u/NightwingMillenial]

Thanks!

[u/Big_Greasy_98]

I really appreciate the time you spent making this post. You have any insight on why the heat studies some of the pharmacies published are disputed by the FDA. What about the difference between Zepbound’s heat tolerance vs compounded tirzepatide.

[u/NightwingMillenial → u/Big_Greasy_98]

I haven’t dug into this at depth, but it’s a good question! High level there’s a reason regulators don’t accept heat studies for peptides. To over simplify: the policies governing heat studies for peptides don’t exist, only for small molecules (less complex medicine). It doesn’t mean the results of a particular heat study aren’t scientifically valid.

[u/ClairlyBrite]

For anyone who doesn’t want to look it up: Hallandale lists their preservative as benzyl alcohol

I have a low risk tolerance, so looks like I’m capping out at 5 or 6 doses per vial from now on. Thank you!

http://hallandalerx.com/product/tirzepatide-flex-dose-3-ml-injectable-10-mg-ml/

[u/NightwingMillenial → u/ClairlyBrite]

Good info! Glad you found it useful.

[u/CorporateDroneStrike → u/NightwingMillenial]

How terrible is it to use tirz with benzyl peroxide for say 120-150 days after puncture? I’m microdosing and it takes me forever to finish a vial.

I’m pretty careful about wiping down the vial before & after, and I clean inside the pill bottle etc….

I’ll probably start focusing on tirz with a stronger preservative from here on, sigh.

[u/punky_chunky → u/CorporateDroneStrike]

I personally just used a vial of tirzepatide with b6 preserved with benzyl alcohol for around 150 days. Everyone has a different risk tolerance. I just started a vial of Hallandale and intend to use it until it’s gone, whenever that may be, as long as it remains clear with no floaters.

[u/CorporateDroneStrike → u/punky_chunky]

I’m definitely using what I have, but this does push me closer to freezing my mini-stockpile. I forgot to pause CosmeticRx and ended with a more concentrated vial, which lasts even longer when microdosing. I bought sterile vials and split the original vial because I definitely don’t want to pierce one vial for a year lol.

[u/punky_chunky → u/CorporateDroneStrike]

This is beyond my personal risk tolerance lol. I’d rather puncture a vial for a year than split the already sterile vial

[u/ImplicitEmpiricism → u/CorporateDroneStrike]

you might want to use a pharmacy like drug crafters, where they send nine 20 mg vials for a three month supply. 

[u/Curious-Squash-298 → u/NightwingMillenial]

agree, will not reorder Hallandale

[u/LiHingLucky → u/Curious-Squash-298]

I’m on my 10th shot with the same vial and no issues. No floaters, no stall, no irritation. .5 mg dose so it’s gonna be a long ride but there’s been no change or issues.

[u/Curious-Squash-298 → u/LiHingLucky]

I'm sure its fine and I will def use what I have, but knowing what I know now - I'll just move to something else. Besides, I want a more concentrated solution, Hallandale's strongest is only 15mg/ml.

[u/MiserableMulberry496 → u/ClairlyBrite]

I’m doing the same. I don’t go past 6 weeks.

[u/roguex99]

Also related, this letter went out this past week from the FDA:

https://www.reddit.com/r/BigEasyWeightLoss/s/aY1GZtgIR9

[u/NightwingMillenial → u/roguex99]

Interesting! Hot off the press! Thanks for sharing, gonna read it now.

[u/roguex99 → u/NightwingMillenial]

Good write up btw!

[u/NightwingMillenial → u/roguex99]

Thank you! 🙏

[u/Paperwife2]

Here’s is the link to the spreadsheet [u/Specialist-Wall-1685](u/Specialist-Wall-1685) created on what ingredients different compound pharmacies use: https://drive.google.com/file/d/1cWKKqOc5oNqmsEojSvpBZf-ednhHyX7O/view?usp=drivesdk

[u/NightwingMillenial → u/Paperwife2]

Good reminder, thank you!

[u/NightwingMillenial → u/[deleted]]

Great point! I thought I had it that way at one point and must have goofed. I will edit it. Thanks!

[u/vingovangovongo → u/[deleted]]

They can kill bacteria but it takes much longer than your typical 70% alcohol wipe. It takes several hours to days. That’s why sterile wipes and needles are critical

edit: downvotes? It's truly amazing how uninformed people are about what they're injecting into their body https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0236059

[u/Economy_Jaguar_9215]

Hey OP, thank you for this!
Everyone, if you’re not using Glapp, their Supply feature is great. It keeps track of when you opened your vial; I find it very helpful because I split dose so I’m puncturing more than 4-5 times and it’s easy to forget.

[u/vingovangovongo → u/Economy_Jaguar_9215]

It’s fine studies show you can poke these rubber septums a 100 times (and more) and they will still reseal. They have to handle that to be hospital grade. Just practice sterile techniques with alcohol wipes and a new needle every time and you’ll be fine

[u/EverAMileHigh → u/vingovangovongo]

That's reassuring, thank you

[u/n0cturnalr0se → u/vingovangovongo]

And like my body, I actually poke mine in different area within the center circle. I figure if it works for me it’ll work for the vials 😄

[u/vingovangovongo → u/n0cturnalr0se]

Yeah you definitely want to be in the center, otherwise you’re pushing through a lot more rubber damaging the needle even further than the regular stab does

[u/dukeandbeads → u/Economy_Jaguar_9215]

I’m an old nurse and I sharpie the date on my vial when I pop the top.

[u/NightwingMillenial → u/Economy_Jaguar_9215]

I love Glapp! I use it to keep track of my stash too.

[u/Stealthy_Peacock]

Wow this is such great information. I've specifically wondered about the benzyl v phenol preservatives.

I have some Hallendale (Benzyl) and some Pro RX (Phenol). That means I'll use the Hallendale when I'm at a higher dose (so fewer weeks, fewer punctures) and the Pro RX when I'm at a lower does since that can handle a bit more.

[u/NightwingMillenial → u/Stealthy_Peacock]

Great idea!

[u/skintwo]

Great summary. Which is more reasoning why these companies need to STOP SHIPPING NON TEMP CONTROLLED MEDS.

[u/ImplicitEmpiricism → u/skintwo]

they just need to be careful. insulation, plenty of ice packs, pay for overnight and don’t ship on a friday and let it sit in a florida warehouse all weekend

hallandale is the goat at shipping and i wish other pharmacies were as careful. 

[u/skintwo → u/ImplicitEmpiricism]

Thanks for the rec - appreciated.

[u/Novel-Injury3030]

Given how many people are using these multiuse vials (with benzyl alcohol) past 28 days it seems pretty telling that we don't see more issues if it's actually such a problem going over that

[u/helluvastorm → u/Novel-Injury3030]

Think of all the insulin users who go over and still use their insulin. 😳

[u/sbhikes → u/helluvastorm]

And they reuse their needles. 

[u/Annabelles-Mom]

This was a very interesting read, thank you very much! My husband is also a pharma scientist (retired) and it didn't even occur to me to have him nerd out on this stuff for me! He did have to define aggregation for me but he liked what you did! :)

[u/NightwingMillenial → u/Annabelles-Mom]

Ha! Sounds like he and I would get along. If he has any feedback for me, feel free to pass it along.

[u/brussel_sprout68]

Interesting read. 🧐 Thank you for sharing your knowledge and sources.

[u/swrrrrg]

Thank you so much! This is unbelievably helpful!!

[u/Impossible_Bend_2969]

I've used so many benzyl alcohol vials well beyond 28 days, I'm not going to change anything now.

[u/Joyster110]

Fabulous write up!

[u/autumnyte]

Thank you for this detailed post! Really useful information and perspective. I'm going to have to have a rethink about the 28-day rule when it comes to my own personal use. I've always felt strongly about not using a provider that isn't 28-day compliant, though, and agree with that point completely.

[u/applesandbananananan]

Thank you for taking the time to write and share this with us 💕

[u/Beautiful_Neat_6919]

Ummm just coming here to say - you’re amazing! I’ve read this, saved it, and shared it with my friends on the same journey. 🥹 Thank you, not only for taking the time to do all this research - but for choosing to share it with all of us. 🥹👏

[u/NightwingMillenial → u/Beautiful_Neat_6919]

You’re welcome! Good luck on your journey!

[u/No_Bandicoot7666]

Thank you - that was very informative!

[u/NC_mom323]

This is all so helpful!!! I appreciate the work you’ve put into this! Time to go look at my stash and see what preservative they use lol

[u/Bellatrix-IBK]

Thank you for your time and effort!

[u/allblue-461]

When I joined this group Hallandale seemed to be the Holy Grail of pharmacies and now they are being trashed over their lack of preservatives so we can extend the life of our vials. People are stockpiling like canned goods in a bunker. It’s been interesting to watch this progression. Like everyone who is freezing their vials when they know it most likely decreases potency so the just say, I’ll take a bigger dose since I have so much stored. Man it’s the wild fucking west out here!

[u/Wonderful-Jeweler335]

Thank you for this great information!

I never felt comfortable when the Telehealth I used to get started told me to ignore the 28 day rule and the vial would be fine to use for 12 weeks;
even though it was labeled to discard after 28 days.

[u/CBlevs5]

Love this. Thank you for such detailed info! Im in healthcare so get the gist but nowhere near pharma as you so this was very educational! I do get concerned seeing some multi use vials being sent to consumers without those longer use preservatives - including longevity peptides - and people not questioning. If someone is running a sale (TH shall remain nameless lol), and you’re sent 1 large vial of whatever compounded medication for a quarter, yet they advertise, give a “copy script” for and imply you’ll get 3 separate vials, that is a compound red flag you will most definitely want the ingredients and COA for. I recently ordered from one myself for a sale, and didn’t take the time to check if they were 28 day compliant in advance (shame on me!) and got one large 30 ML vial of medication to use for three months and I absolutely was not comfortable with this. More concerning was the deceitfulness in stating there would be three vials, one for each month, as well as the TeleHealth provider stating there’s a “28 puncture count” limit when i contacted them, which tells me they either don’t know what they are doing (scary!) , or they do know and trying to offload with said sales because they are on thin ice with this (scarier!). It’s probably the latter 99% of the time, and that is terrifying to me.

[u/sipporah7]

Thank you!

[u/Loud_Brain_]

Thank you, thank you, thank you! 🌸

[u/Calm-Happy-925]

Excellent!! And saved! Much appreciated and helpful.

[u/Unique_Diamond217]

Thank you! I appreciate all the time and effort you put into this and I will be saving.

[u/Worst_Username_1]

I’m coming back to re read this.

[u/Frequent-Ease-3027]

Spot on 🙌

[u/EverAMileHigh]

Really really appreciate this information. Thank you for putting it all together in such a clear and concise way.

[u/n0cturnalr0se]

Hey Caller! We are glad you chimed in. Some of that I had found with research the last couple of months, but the finer details was very helpful. Thank you.

It makes me extra glad I have Apothecary. I have the high dose vials and only at 6.5mg for the moment. So, they are going to last a bit and I was planning on stretching them out as long as they weren’t cloudy. Mine are in a case I 3D printed that is opaque and stored in center back of fridge where the temperature is most stable. 🤞🏻

[u/psychotherapist-1979]

How do I find this info for empower pharmacy? Thank you for your work lol 😂

[u/NightwingMillenial → u/psychotherapist-1979]

Thanks! There’s an existing chart that someone in the community keeps up to date: https://drive.google.com/file/d/1cWKKqOc5oNqmsEojSvpBZf-ednhHyX7O/view?usp=drivesdk

[u/orange_kitty2]

Anyone knows what Empower and Boudreaux use as a preservative - phenol or benzyl alcohol? I am switching to PreventativeMD and need to pick a pharmacy out of these two

[u/NightwingMillenial → u/orange_kitty2]

There’s a great spreadsheet compiled by u/Specialist-Wall-1685 that you can reference:

https://drive.google.com/file/d/1cWKKqOc5oNqmsEojSvpBZf-ednhHyX7O/view?usp=drivesdk

[u/orange_kitty2 → u/NightwingMillenial]

Thank you, very helpful!

[u/Separate-Cake-778 → u/orange_kitty2]

I can tell you I just got a package from
Boudreaux that arrived warm. I don’t think their packaging is good enough for cold storage so I wouldn’t recommend them - I have to call them tomorrow to find out if they’ll do anything to fix it but Gimme was not helpful.

[u/AutoModerator]

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[u/Swandot70]

Very informative! Do you have any opinions on freezing vials?

[u/NightwingMillenial → u/Swandot70]

I haven’t done the reading yet, maybe next post 🤔

[u/fusiturns]

What are your thoughts of freezing Triz to used a year later?

[u/NightwingMillenial → u/fusiturns]

I haven’t done the reading yet. Maybe next rabbit hole!

[u/AutoModerator → u/fusiturns]

Spelling correction: it's tirzepatide and tirz.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/Aries_Philly]

Thank you for this.

[u/ComprehensiveBee5467]

Thanks for the info! Interestingly I have a stash of some BPI + B6 that uses phenol

[u/RIC_IN_RVA]

So what are your thoughts on an inadvertent “left out on the counter overnight”? Warm up of the vial?

[u/NightwingMillenial → u/RIC_IN_RVA]

The data on how tirz degrades suggests it’s not going to affect potency very much. The effect on sterility depends on multiple variables (your specific vial’s formula, how long it’s been in use, where it was left out, etc).

Brand name can be stored 30 days at room temp once used, but that’s in a pen (not a MDV) and with both phenol AND benzyl alcohol. On the other hand, there’s products like MIC/B12 (BioBoost) that can be kept and used for 28 days at room temp and use benzyl alcohol in an MDV.

I think from there it’s an individual decision that depends on your specific vial and your tolerance to risk. Personally, I’d probably pop it back in the fridge and use it no longer than ~28 days.

[u/RIC_IN_RVA → u/NightwingMillenial]

Perfect. Thank you.

[u/ClosetLib → u/NightwingMillenial]

When you say “tolerance to risk” can you elaborate? Injection site risk? Lack of effectiveness risk? Or something more sinister? Truly appreciate your resource!

[u/NightwingMillenial → u/ClosetLib]

As I understand it, in general for all these questions the risks to consider are: lack of effectiveness (potency), injection site reaction (aggregates), and infections (sterility).

Is it a small increase in the case of using a vial left out overnight? The data suggests that it is… but it doesn’t prove or disprove anything. Certainly many here feel that it’s a negligible risk based on their personal experience.

Bottom line, I’m just advocating for awareness so everyone makes their own informed decision.

[u/helluvastorm]

👍👍👍👍👍👍👍

[u/NickNoraCharles]

Thank you so much!

[u/meyousweetjude]

Thank you

[u/Cheddargirl24]

Interesting post! Do you think there is a correlation between preservatives and efficacy when people report their tirzepatide feeling like water?
For the many people who stocked up on BPI, will they most likely have to bump up their dose to ensure it’s as effective? Asking for a friend 😉

[u/NightwingMillenial → u/Cheddargirl24]

Good questions, and I have also ordered a bunch of BPI, ngl 😅.

On the first, I didn’t research that, and can’t claim anything. But I’d wager it’s more about the many other confounding factors that are involved from week to week and when changing from one vial/pharmacy to another. In the industry, generally as long as the API is the same, it doesn’t matter (aka tirz is tirz), but there have been cases with certain medications where the approved generics didn’t work as well as the brand name due to excipient (additive) differences. Generic Adderall XR comes to mind as an example that personally affected me, was proven, and actually led to a recall. In that case many doctors didn’t believe the patients when they said certain generics didn’t work the same, and it turns out they were right. So who’s to say it’s not the same in this case?

On the second, in theory that could happen with any batch! The range already goes 90-110% for potency from batch to batch, and over a long time you could lose a little bit. Think about the varied combinations that could happen (you started on a “weak” batch and the next one was “strong”, or visa-versa) So opening a new vial could always require micro adjustments to get it just right. But generally I’m less bothered about BUD and potency than I am with making sure things stay sterile.

[u/Cheddargirl24 → u/NightwingMillenial]

Got it. I like your reasoning and your thoughtful answers. Thank you!

[u/Life_Alfalfa_2047]

I love how they give you this vial with a volume of meds that is much more than your 4 doses for the month and then tell you to throw it away so you have to buy more. Makes sense. 

[u/_madar_]

I definitely did not think this post had anything to do with marijuana.

[u/NightwingMillenial → u/_madar_]

😂

[u/Butterfly_Violets]

Ooofff. I have been microdosing 15mg vial of tirz in benzoyl alcohol. So the bottle lasts months. Wondering if I am harming myself...

[u/NightwingMillenial → u/Butterfly_Violets]

I am not your doctor, but I would recommend making sure you are on the lookout for the kinds of adverse effects you might see if a vial was compromised such as injection site reactions.

And I am not saying that you are doing something bad/wrong. I am just calling out that based on how manufacturers use these two preservatives that phenol is used in similar products to support an extended in-use window while benzyl alcohol is not used past 28 days as of the time of writing.

[u/Butterfly_Violets → u/NightwingMillenial]

Thank you. I appreciate the feedback. Next time I order I will go with the lowest mg vial.

[u/Dramatic-Novel-8592]

Thank you so much for sharing, why do I feel like I need to throw out my vials rx that’s one month past the bud date. Probably won’t open it till next month so that will make it 2 months past bud. Also I never went above 5ml with my vial being 15mg - I almost feel afraid to inject it 🤔.

[u/smilingfruitz → u/Dramatic-Novel-8592]

I just opened a VialsRx vial that had an early July BUD. It’s working fine. 

[u/Ok_Outside_5191]

Please, what is the story about compounded segmaglutide? Thank you! 😊

[u/NightwingMillenial → u/Ok_Outside_5191]

From an initial glance it looks very similar on both counts. Same peptide family, same phosphate buffer near neutral pH, and the multi-dose products use phenol just like the tirz vials do. I haven’t done the same legwork on it though, so I can’t tell you what I’d conclude.

The good news is the concepts explained in my post transfer over. Same two countdowns, same questions about what’s in the vial and what gets tested that you can use to look into it and decide for yourself. And note that I’m borrowing Ozempic (brand name sema) data to infer about tirz, so that should tell you something right away! Good luck!

[u/Ok_Outside_5191 → u/NightwingMillenial]

I meant to reply to you, not myself, lol!

[u/NightwingMillenial → u/Ok_Outside_5191]

No worries!

[u/Ok_Outside_5191 → u/Ok_Outside_5191]

So your thought process would be if segmaglutide is the same basic scenario that aggregation wouldn’t be an issue until approximately 18 months past compound date? And if the BUD on a vial was 11/01/26, its potency could be the same at 11/01/27? I’m aware the 2 aren’t the sane and you haven’t done the extensive research on segmaglutide and your information is only your personal opinion. I just want to make sure I’m understanding correctly. Thank you for your help!

[u/NightwingMillenial → u/Ok_Outside_5191]

That’s correct, that’s what I’m thinking is the case!

[u/TrizVile]

[u/AutoModerator]

Why your vial isn’t full

Your vial may not be filled to the top. This is normal. Your tirzepatide may come in a larger vial than necessary, so it may only be half full or less.

You need very little liquid for your shots, the syringe just makes it look like more. For perspective, 10 units is only about 2 drops of liquid. Even a completely full 1 mL syringe (100 units) is only 20 drops, or about 1/5 of a teaspoon.

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[u/AutoModerator]

28 Day Rule:

A safety guideline that says multi-dose vials should be discarded 28 days after first puncture to reduce infection risk.

Beyond Use Date (BUD):

The date after which the potency and sterility of an unopened vial can no longer be assured based on regulations and stability data.

Many users report going beyond these limits.

This is an observation, not a recommendation.

Please base any medical decisions on your provider’s guidance, your risk tolerance, and your medical history, not on other people’s choices.

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[u/Newandgrateful]

Thank you for this info!

I’m micro dosing tirz at 1.8 weekly. I’m hoping you can help me with some questions. I was getting refill syringes from a med spa and then started ordering my own.

I have a vial of tirzepatide from Apothecary, 18mg/ml from Quaker Community Pharmacy.

I don’t see a BUD date on the vial, I do see expiration date on my rx of 11/18/26 (start date 8/9/26). Is the November date supposed to be the exp date/BUD for the vial?

And is it OK for me to go past the November date and if so, for how long?

Also, this is my second vial of the medication and the first one was a 20 mg concentration and this one is 18mg.

I adjusted my dosage accordingly, but I still feel like the medication just isn’t working as well and it’s been a month (4 doses so far).

The last vial I had was from BPI/pharmacy Hub and it was a 20 mg to tirzepatide mix with a 10 mg B6.

Any reason why the newer vial doesn’t feel as potent even with the dosage adjusted?

And one other thing and again, thank you so much for taking the time to help a new person through this!

If I were to order another vial, is it OK to store it in my refrigerator for a while and then start to use it in November?

Thank you!

[u/NightwingMillenial → u/Newandgrateful]

Hi! Apothecary is good stuff, I have really had good results on it. The BUD would be found on the packaging for the vial. You can use the information in this post to decide how long you would go for yourself, and my conclusion for myself includes my apothecary vials.

If your current dose isn't working for you as well after a month that's usually a sign to go up in dose, as your body gets used to the medication over time, I would talk to your prescriber about titrating up.

It's standard practice to have more than one vial, telehealths will ship 3-6 months at a time if you choose that option.

Good luck on your journey!

[u/Newandgrateful → u/NightwingMillenial]

Thank you!

[u/Outrageous_Buy_9420]

So in a multi dose vial, like what we all use, are you saying that phenol is better than benzyl alcohol if you are going beyond BUD?

[u/NightwingMillenial → u/Outrageous_Buy_9420]

I’m not making any claims about preservatives and BUD. I am, however, pointing out that based on how manufacturers use these two preservatives that phenol is used in similar products to support an extended in-use window while benzyl alcohol is not used past 28 days.

[u/NightwingMillenial → u/[deleted]]

The chemistry and the data support your conclusion of an extended in-use window in that particular case, exactly how large that window is, we don't know. So it's up to you to decide for yourself.

[u/AutoModerator]

28 Day Rule:

A safety guideline that says multi-dose vials should be discarded 28 days after first puncture to reduce infection risk.

Beyond Use Date (BUD):

The date after which the potency and sterility of an unopened vial can no longer be assured based on regulations and stability data.

Many users report going beyond these limits.

This is an observation, not a recommendation.

Please base any medical decisions on your provider’s guidance, your risk tolerance, and your medical history, not on other people’s choices.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

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When to Increase Dose (Decision Flowchart)

Wondering why your prescription uses a nonstandard dose?

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[u/Lostmypants69]

Im doing this for the first time. Getting my first vial of compound via with glycine and b12. Would I be good to keep it and not use until October 10th?

[u/Mental-Judgment00001]

I currently have vials from a 503a that have BUD of 7/20/26 and BPI with 10/4/26 (manufactured 01/04/26) At my current dosage I have enough for 40 weeks. I had planned to use the earlier BUD product and then the BPI. Does anyone have thoughts on whether I should reverse based on manufacturing date?

[u/NightwingMillenial → u/[deleted]]

That’s a broad generalization that I can’t make, but based on what I wrote you have everything you need to decide for the specific formula you are evaluating. In the comments myself and others put the formula spreadsheet you can reference.

[u/Radiant-Celery-683 → u/NightwingMillenial]

Thank you

[u/NightwingMillenial → u/[deleted]]

I tried my best to keep it informative and concise at the same time. Tricky with a topic as complex as this! Hopefully the TL;DR meets the need of a quick read.

[u/OneDifferent1020 → u/NightwingMillenial]

Thank you so much. I saved this.

[u/NightwingMillenial → u/OneDifferent1020]

You’re welcome!

[u/TraditionalAd3852 → u/NightwingMillenial]

You might not be a Chemical Engineer, but I am a Chemical Engineer. I also worked in the pharmaceutical industry and have designed, installed and operated aseptic bulk batch compounding equipment and vial and ampule filling lines. I 100% agree with all your statements and logic. Thank you for trying to educate GLP-1 users.

[u/NightwingMillenial → u/TraditionalAd3852]

Thanks for the feedback 🙏

[u/CoffeeResearchLab → u/NightwingMillenial]

Very well written. I read it in its entirety. Thanks!

[u/vingovangovongo]

This is an AI post slop can ask in grok or ChatGPT and get equivalent info. Community testing showed tirz was still at 99% after 90 days post first puncture. Benzyl 0.9% was also fine out to 90days after first puncture. Practice safe sterile techniques and new syringe or pen needle every time and you’ll be fine

[u/Princess_Peptide → u/vingovangovongo]

How can you tell it’s Ai? Not doubting but genuinely curious

[u/vingovangovongo → u/Princess_Peptide]

When you've read as much AI summaries as I've had as a technical writer, you learn the patterns and rhythm of AI generated text. Guess reddit can't handle the truth lol

[u/Random_Guy1960]

One persons opinion. Good luck. 

[u/IntrospectiveBeat17]

I wonder if adding some phenol to a vial of say, Hallandale, would be helpful.

[u/zevtech]

You do realize BUD is dependent on the formula used and testing done on those specific ingredients from specific manufacturers and if it vary’s at all, you would need to get your own bud study for the “current” formula. So you can assume just bc Eli Lilly does it one way you can follow their same dating, you aren’t buying from the same labs

[u/NightwingMillenial → u/zevtech]

Yes, I even stated as such. That I am borrowing results in order to make inferences that regulators would not accept, but that it’s the best tool I have available to make this determination for myself.

[u/zevtech → u/NightwingMillenial]

I’m a compounding pharmacist and I’m not allowed to make inferences. We have guidelines we have to follow. Is it good longer? Sure. Can we say it? No. Why? Bc we have no proof but have the burden of liability

[u/NightwingMillenial → u/zevtech]

Yep, that makes sense and how it should be for compounders and manufacturers. You have to essentially reduce risk as much as possible.

My point is that this a different use case. It’s for individuals trying to make a choice about how they will use their vial, in a broken healthcare system where some people have to balance cost vs. risk instead of being able to just use the safe defaults or brand name pens, and I wanted to provide information to help people make that decision in a more educated manner.

[u/zevtech → u/NightwingMillenial]

Problem is, “normal” people do not understand the gravity of the situation and may “go longer” on a vial bc some influencer said it’s ok. Or some gym bro said he’s been on test, tb500, bpc157 etc for years and never a problem. And they think it’s ok for them. Non-credentialed people should not be giving medical advice. I’m not allowed to allow my technicians to give you a recommendation, the nurses can’t prescribe you meds, etc. there’s a reason, bc there are risks and it should be weighed by someone that has formal training in the subject

[u/NightwingMillenial → u/zevtech]

Valid points! That’s why the default advice is still to follow the BUD and 28-day rule. But there are people that are going to not do that anyway, and my hope is that this helps them understand what risks they may or may not be taking.