Do B12 injections go bad? How long is B12 good for after the expiration date? These are questions that readers who bought our methylcobalamin B12 vials ask us all the time.
We decided to dedicate an entire article to these questions 🙂
Do B12 Shots Expire?
Obviously, yes. What in the world does not expire at some point? However, the actual expiration date is often way past the date stamped on the product:
Properly stored vitamins are likely safe past their expiration date for up to two years. Water-soluble vitamins, such as B12 and C, are more likely to lose their potency quickly. Expired vitamins will not become poisonous, but rather lose their potency. Exceptions to this rule are if supplements are stored in wet, hot, or humid areas and produce mold. Moldy vitamins should not be consumed.
Shanna Levine, MD, Mount Sinai Hospital
The expiration date on meds is the time limit that the dosage potency is guaranteed. After that time, the potency may be less (but often is not). It is the rare drug (some types of tetracycline) that become toxic if outdated. Nevertheless, a pharmacy can not dispense, and a physician is not supposed to administer a medicine beyond its expiration date.
Dr. Arthur Heller, HealthTap
Generally speaking, vitamin B12 is not a standard medication, at least not in the US or the UK. It is made in compounding pharmacies, and the risk of bacterial contamination grows as the product ages. However, there are ways to mitigate the risks.
Liquid B12 Expires Faster Than Dry B12
Does liquid B12 expire faster than dry B12? Yes, and this is why we sell our injectable methyl B12 in powder form. In fact, methylcobalamin B12 is extremely stable when dry, and will retain its potency even at temperatures as high as 315°C / 600°F.
We stamp an expiration date of a little less than a year on each new batch, since an expiration date is required to be on all vitamins. This is the expiry date assuming you dissolve the B12 in saline immediately when you receive the vial. However, if you were to keep the B12 in its dry form, it will actually last for years to come.
The Risk of Photolysis
Even though B12 is very stable when dry, it is also extremely light-sensitive in liquid form. In other words, it easily undergoes photolysis – that is, destruction by light – unless kept in proper conditions. This is another reason why we prefer to sell our B12 in dry form. It ensures that it hasn’t been spoiled by light (or high temps) during delivery.
It’s also why we advise to wrap our B12 vial in aluminum foil right after you dissolve it in saline. Our vials are made of amber glass, which blocks about 66% of light. Covering the vial with aluminum foil will fully protect it. This point is absolutely crucial.
How Quickly Do B12 Injections Expire When Exposed to Light?
Anyway, just how quickly does the B12 degrade in exposure to light? If you want to learn more about the photolysis of B12, read our article here. The key takeaway is that under normal use – drawing from an aluminum-covered vial into a transparent syringe, and injecting within a minute or two – there’s nothing to worry about.
How to Keep Your B12 From Going Bad
Bottom line, B12 is extremely stable when dry, and will last this way for many years. Even in liquid form, it will last for a year or two past the expiration date stamped on it, unless it’s compromised by mold, in which case you should dispose of it immediately. This is not to say that we recommend injecting non-moldy, expired B12 injections. With injectable B12 being so affordable, it’s better to just obtain a new supply.
However, let’s imagine for a moment that there were no expiration date stamps in the world. How do you extend the life of your injectable B12? Here are some tips:
- B12 is remarkably stable to both heat and light when dry. Liquid formulations spoil faster, either due to contamination, or to photolysis (destruction by light). Therefore, keep your injectable B12 in dry form for as long as you can (if you can).
- If you have already dissolved the B12, or if you bought your injectable B12 in liquid form to begin with, then store it properly. This means making sure the vial is covered with aluminum foil, and placing it out of sunlight, preferably in a dark, cool environment (5-25°C / 41-77°F), protected from humidity. Fridge is good.
- For antimicrobial protection, avoid rubber closures if you can. These closures actually allow ingress of contamination from the hole through which the needle passes, because it is too large to keep out bacteria. Also, rubber closures are prone to contamination by rubber additives. If you bought a B12 vial from us, maintain its integrity by ensuring it’s tightly closed. Make sure the needle you’re using is sterile, taken straight from its bag without having been laid flat on any surface prior.
As for the key question, now – is it OK to take expired vitamin B12 injections if you follow the above tips? Probably nothing’s going to happen, but why risk it? Even if you took good care of your B12, we still advise to stay well within the expiration date stamped on it, and to avoid expired B12 shots if you can.
Not worth the risk.