5 ms·

The expiry date put on medicines are sometimes absurd. Certainly antibiotics may break down, but why would aspirin have an expiry date that's only a year or two

The expiry date put on medicines are sometimes absurd. Certainly antibiotics may break down, but why would aspirin have an expiry date that's only a year or two away? It's a simple stable molecule that would probably last decades. Anyone know what's up with that?

maxerickson 10y ago
It is sort of a promise the drug will still work. Short expiries don't cost them sales and limit bad publicity and other hassles.
sndean 10y ago
It's simply a guarantee of full potency of the drug. A while ago, a study (currently looking for it...) found ~90% of OTC drugs were perfectly fine 10+ years after the expiry date, IIRC. And most antibiotics should be just as stable as aspirin.
- nommm-nommm 10y ago
  The US military operates the Federal Shelf Life Extension Program which, from what I understand, regularly tests federal stockpiles of medications to avoid waste. http://www.astho.org/Programs/Preparedness/Public-Health-Emergency-Law/Emergency-Use-Authorization-Toolkit/Federal-Shelf-Life-Extension-Program-Fact-Sheet/ http://www.astho.org/Programs/Preparedness/Public-Health-Eme...
ridgeguy 10y ago
Aspirin is acetylsalicylic acid. When it's exposed to water vapor, the acetyl group comes off and combines with water to make acetic acid, which is the acid in vinegar [1]. This happens pretty fast. An open bottle of uncoated aspirin tablets can start to smell of vinegar in a day or two, depending on the local relative humidity. If you smell vinegar when you sniff your bottle of aspirin, toss the bottle. Why? Well, the other hydrolysis reaction product (salicylic acid) removes the outer layer of the skin and is used, for example, to remove warts [2]. Not something you want in your stomach. [1] http://www.kii3.ntf.uni-lj.si/analchemvoc2/file.php/1/HTML/SPEKTRA/kinetics2.htm http://www.kii3.ntf.uni-lj.si/analchemvoc2/file.php/1/HTML/S... [2] https://en.wikipedia.org/wiki/Salicylic_acid https://en.wikipedia.org/wiki/Salicylic_acid
- tossaway1 10y ago
  Isn't your stomach already extremely acidic...?
  - enknamel 10y ago
    Not all acids are the same. What's at play isn't only the amount of free protons but also what else is disassociating. For instance, hydrofluoric acid is considered a weak acid but it can severely burn (pretty slowly but it will get you) or even kill you. The fluoride group will consume the calcium ions in your blood and possibly send you into cardiac arrest.
  - rcthompson 10y ago
    Any compound with a hydrogen ion that can dissociate in solution is technically called an acid, but that doesn't mean it's acidic properties are the most relevant.
- ItsDeathball 10y ago
  I had always wondered why aspirin tended to smell like vinegar and rarely helped with headaches. It's quite satisfying to have an explanation for both.
- mmmpop 10y ago
  Thanks, this is a great comment.
- skookumchuck 10y ago
  Sounds like a good argument for coating the pills.
- Symbiote 10y ago
  In general, expired or unwanted medicine should be taken to a pharmacy or similar for proper disposal.
sokoloff 10y ago
Bottled water has an expiration date. 280 million year old salt. Expires in 2019: http://imgur.com/a/Sug5c http://imgur.com/a/Sug5c
- Filligree 10y ago
  That's incredibly lucky, then. Imagine digging the salt out of the ground just before it expires, but still with enough time left to sell it.
- ijidak 10y ago
  Haha. That is hilarious. 280 million years old, the preservative of preservatives. In many other countries (developing especially) they don't even pay attention to food expiration dates. We have eyes and a nose and they're really good at telling us when food shouldn't be eaten. I have a friend who is from Nigeria and was selling bags of rice at her shop. Food inspectors told her she had to throw the rice away because it had expired. She was devastated because she wasn't even used to thinking about rice expiring, especially not when it's just a few months old. Welcome to the West.
  - Symbiote 10y ago
    The "best before" time on the rice in my European cupboard is one year. It's still legal to sell it after that date [1]. The EU is considering[2] removing rice from the requirement to have a "best before" date at all, which is already the case for a few things[3], like salt and sugar. [2] https://ec.europa.eu/food/safety/food_waste/eu_actions/date_marking_en https://ec.europa.eu/food/safety/food_waste/eu_actions/date_... [3] Annex X http://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:32011R1169#d1e32-57-1 http://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:320... [1] https://www.approvedfood.co.uk/ https://www.approvedfood.co.uk/ for example, you can search "rice".
- DonHopkins 10y ago
  Even homeopathic medicine is required to have an expiration date, if only for legal compliance. Homeopathic medicine should be required to actually have an effect, if only for legal compliance. http://hpathy.com/ask-homeopathy-doctors/do-homeopathic-medicine-expire/ http://hpathy.com/ask-homeopathy-doctors/do-homeopathic-medi...
hehheh 10y ago
It shrinks the size of any recalls that may be required should something go wrong. (I don't know this for a fact, however.)
ekianjo 10y ago
Stability tests are actually pretty expensive, and you need to demonstrate that your shelf life is valid across the shelf life you request - so usually 2-3 years is about the max companies request, but it's good enough, and they need to ship their drugs out as fast as possible. Sometimes you see drug shelf life extensions post-release, but that's not always really worth the effort.
tominous 10y ago
This is a huge deal with drugs that can cost $10k per vial. The manufacturers have no incentive to test for longer periods: it would just mean less revenue and more risk. And as I've mentioned before, physicians are very conservative and don't like stepping outside what other people do even if the basic research is there. For example, the ability to pool leftover amounts of Yervoy (ipilimumab) among patients could save thousands of dollars each. The research so far shows that cancer drug Yervoy remains sterile, stable and effective for at least a month [1] but the manufacturer's guidelines say to use immediately after opening and throw away the rest. (Ironically the independent researchers couldn't afford to do a larger study because the vials were so expensive in the first place!) It also limits how the drugs are delivered. For example, IL-2 (as a cancer immunotherapy) might be safer, more effective and more convenient as a single continuous infusion over a few weeks [2]. But the guidelines say to use immediately and throw away the excess. It also limits research into what I think is the most promising near-term approach to cancer: intra-tumoral immunotherapy (with frequent low doses of e.g. ipi, nivo, IL-2 into lesions). Unfortunately this is way too expensive if you have to throw away 99% of a vial for each injection. [1] https://www.ncbi.nlm.nih.gov/m/pubmed/26922168/ https://www.ncbi.nlm.nih.gov/m/pubmed/26922168/ [2] https://www.ncbi.nlm.nih.gov/m/pubmed/10996039/ https://www.ncbi.nlm.nih.gov/m/pubmed/10996039/
jzl 10y ago
Could also be related to the fact that they need to account for a massive range of storage conditions across all consumers. Some people live in climates where it hits 90-100+ degrees for many months of the year and may not have AC. Some people might keep their bottles on a counter that receives sunlight. And there are huge ranges in humidity. There's probably a big range in medicine lifespan between the best and worse cases there.

maxerickson 10y ago

It is sort of a promise the drug will still work. Short expiries don't cost them sales and limit bad publicity and other hassles.

sndean 10y ago

It's simply a guarantee of full potency of the drug. A while ago, a study (currently looking for it...) found ~90% of OTC drugs were perfectly fine 10+ years after the expiry date, IIRC. And most antibiotics should be just as stable as aspirin.

nommm-nommm 10y ago
The US military operates the Federal Shelf Life Extension Program which, from what I understand, regularly tests federal stockpiles of medications to avoid waste. http://www.astho.org/Programs/Preparedness/Public-Health-Emergency-Law/Emergency-Use-Authorization-Toolkit/Federal-Shelf-Life-Extension-Program-Fact-Sheet/ http://www.astho.org/Programs/Preparedness/Public-Health-Eme...

ridgeguy 10y ago

Aspirin is acetylsalicylic acid. When it's exposed to water vapor, the acetyl group comes off and combines with water to make acetic acid, which is the acid in vinegar [1]. This happens pretty fast. An open bottle of uncoated aspirin tablets can start to smell of vinegar in a day or two, depending on the local relative humidity. If you smell vinegar when you sniff your bottle of aspirin, toss the bottle. Why? Well, the other hydrolysis reaction product (salicylic acid) removes the outer layer of the skin and is used, for example, to remove warts [2]. Not something you want in your stomach. [1] http://www.kii3.ntf.uni-lj.si/analchemvoc2/file.php/1/HTML/SPEKTRA/kinetics2.htm http://www.kii3.ntf.uni-lj.si/analchemvoc2/file.php/1/HTML/S... [2] https://en.wikipedia.org/wiki/Salicylic_acid https://en.wikipedia.org/wiki/Salicylic_acid

tossaway1 10y ago
Isn't your stomach already extremely acidic...?
- enknamel 10y ago
  Not all acids are the same. What's at play isn't only the amount of free protons but also what else is disassociating. For instance, hydrofluoric acid is considered a weak acid but it can severely burn (pretty slowly but it will get you) or even kill you. The fluoride group will consume the calcium ions in your blood and possibly send you into cardiac arrest.
- rcthompson 10y ago
  Any compound with a hydrogen ion that can dissociate in solution is technically called an acid, but that doesn't mean it's acidic properties are the most relevant.
ItsDeathball 10y ago
I had always wondered why aspirin tended to smell like vinegar and rarely helped with headaches. It's quite satisfying to have an explanation for both.
mmmpop 10y ago
Thanks, this is a great comment.
skookumchuck 10y ago
Sounds like a good argument for coating the pills.
Symbiote 10y ago
In general, expired or unwanted medicine should be taken to a pharmacy or similar for proper disposal.

sokoloff 10y ago

Bottled water has an expiration date. 280 million year old salt. Expires in 2019: http://imgur.com/a/Sug5c http://imgur.com/a/Sug5c

Filligree 10y ago
That's incredibly lucky, then. Imagine digging the salt out of the ground just before it expires, but still with enough time left to sell it.
ijidak 10y ago
Haha. That is hilarious. 280 million years old, the preservative of preservatives. In many other countries (developing especially) they don't even pay attention to food expiration dates. We have eyes and a nose and they're really good at telling us when food shouldn't be eaten. I have a friend who is from Nigeria and was selling bags of rice at her shop. Food inspectors told her she had to throw the rice away because it had expired. She was devastated because she wasn't even used to thinking about rice expiring, especially not when it's just a few months old. Welcome to the West.
- Symbiote 10y ago
  The "best before" time on the rice in my European cupboard is one year. It's still legal to sell it after that date [1]. The EU is considering[2] removing rice from the requirement to have a "best before" date at all, which is already the case for a few things[3], like salt and sugar. [2] https://ec.europa.eu/food/safety/food_waste/eu_actions/date_marking_en https://ec.europa.eu/food/safety/food_waste/eu_actions/date_... [3] Annex X http://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:32011R1169#d1e32-57-1 http://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:320... [1] https://www.approvedfood.co.uk/ https://www.approvedfood.co.uk/ for example, you can search "rice".
DonHopkins 10y ago
Even homeopathic medicine is required to have an expiration date, if only for legal compliance. Homeopathic medicine should be required to actually have an effect, if only for legal compliance. http://hpathy.com/ask-homeopathy-doctors/do-homeopathic-medicine-expire/ http://hpathy.com/ask-homeopathy-doctors/do-homeopathic-medi...

hehheh 10y ago

It shrinks the size of any recalls that may be required should something go wrong. (I don't know this for a fact, however.)

ekianjo 10y ago

Stability tests are actually pretty expensive, and you need to demonstrate that your shelf life is valid across the shelf life you request - so usually 2-3 years is about the max companies request, but it's good enough, and they need to ship their drugs out as fast as possible. Sometimes you see drug shelf life extensions post-release, but that's not always really worth the effort.

tominous 10y ago

This is a huge deal with drugs that can cost $10k per vial. The manufacturers have no incentive to test for longer periods: it would just mean less revenue and more risk. And as I've mentioned before, physicians are very conservative and don't like stepping outside what other people do even if the basic research is there. For example, the ability to pool leftover amounts of Yervoy (ipilimumab) among patients could save thousands of dollars each. The research so far shows that cancer drug Yervoy remains sterile, stable and effective for at least a month [1] but the manufacturer's guidelines say to use immediately after opening and throw away the rest. (Ironically the independent researchers couldn't afford to do a larger study because the vials were so expensive in the first place!) It also limits how the drugs are delivered. For example, IL-2 (as a cancer immunotherapy) might be safer, more effective and more convenient as a single continuous infusion over a few weeks [2]. But the guidelines say to use immediately and throw away the excess. It also limits research into what I think is the most promising near-term approach to cancer: intra-tumoral immunotherapy (with frequent low doses of e.g. ipi, nivo, IL-2 into lesions). Unfortunately this is way too expensive if you have to throw away 99% of a vial for each injection. [1] https://www.ncbi.nlm.nih.gov/m/pubmed/26922168/ https://www.ncbi.nlm.nih.gov/m/pubmed/26922168/ [2] https://www.ncbi.nlm.nih.gov/m/pubmed/10996039/ https://www.ncbi.nlm.nih.gov/m/pubmed/10996039/

jzl 10y ago

Could also be related to the fact that they need to account for a massive range of storage conditions across all consumers. Some people live in climates where it hits 90-100+ degrees for many months of the year and may not have AC. Some people might keep their bottles on a counter that receives sunlight. And there are huge ranges in humidity. There's probably a big range in medicine lifespan between the best and worse cases there.