I was wondering. Walk anybody know if aspirin has gone bad when that starts smelling of vinegar? I have noticed that as soon as I open up a new bottle that aspirin that has little odor. ~ a few month that starts to pickup the vinegar odor.

You are watching: Why does old aspirin smell like vinegar


Per a Pharmacist girlfriend at occupational (I work in a hospital pharmacy): That means it has gone off, and also do not use it. Discard it automatically so you don’t forget it’s off, and accidentally usage it.

Are the two chemically similar? Aspirin = acetylsalicylic acid, Vinegar = acetic acid.Does that account for the similar smell?


Per a Pharmacist girlfriend at job-related (I occupational in a hospital pharmacy): That method it has gone off, and also do not usage it. Discard it instantly so you don’t forget it’s off, and also accidentally use it.

What specifically does “gone off” entail? has actually it lost potency, or space there harmful effects?

I’ve constantly used aspirin even when it has actually “gone vinegary”, and also haven’t had any noticeable problems. It still appears to work simply fine also.

In the visibility of too much moisture, aspirin breaks down to acetic acid and also salicylic acid. A pass out smell of vinegar is OK because that aspirin. But the more powerful the smell, the more the aspirin has broken down.


In the presence of extreme moisture, aspirin breaks down to acetic acid and also salicylic acid. A faint smell the vinegar is OK for aspirin. Yet the stronger the smell, the much more the aspirin has broken down.

I have actually heard moisture and medicine room a poor combination. I store all mine meds in the linen closet. Still, mine aspirin suffers premature failure. Ns wonder if removing the desiccant indigenous the bottle accelerated the process?




I wonder if remove the desiccant native the bottle sped up the process?


It certain would. The hydrolysis of aspirin (AKA “going bad”) involves the addition of a water molecule, convert the acetyl group into a totally free acetate i.e. Vinegar.The dessicant is over there to suck up the water and also prevent that reaction.

I don’t have actually a point out for this and could be seriously misremembering, yet I recall analysis somewhere that salicylic mountain is a painkiller choose acetylsalicylic acid, however is a lot stronger stomach irritant. Suspect that, you’ll profession trade her headache because that a gut pains if you take it Aspirin that’s unable to do “off”.

Making aspirin is a fairly common experiment in introductory organic chemistry courses, and I doubt that “Explain why one old bottle of aspirin can smell the vinegar” is a very common inquiry for those experiments. As soon as I made aspirin, the lab instructor was an extremely excited, because we were making a compound that almost everyone has actually used – a medicine drug. I was much less impressed, since making aspirin is very easy, listed that you start with a party of salicylic acid:

2 salicylic acid + acetic anhydride --sulfuric acid–> acetylsalicylic acid + water

(Acetic anhydride is 2 molecules the acetic mountain stuck with each other at the acid part.)

This is referred to as a Fischer esterification. The product is one ester, i beg your pardon is the product of one alcohol’s -OH group joining v an acid’s -COOH group. (In this case, salicylic acid, which additionally has an -OH group, is the alcohol.) The reaction is reversible, so the is no a good way of creating esters – each time you do a molecule that the product, yes sir a possibility it’ll go ago to the beginning materials, for this reason the returns are regularly low.

See more: Guys Of Reddit, What Do You Mean When A Guy Says Your Cute ? 15 Hidden Meanings

There are many different ways that one ester can be broken down into its acid and alcohol components by the addition of a molecule of water. This is called hydrolysis, ‘water-splitting’. Esters break down readily in the existence of a map of mountain or base. Yet the reaction likewise proceeds through water under neutral conditions:

aspirin + water --> salicylic mountain + acetic acid

Water vapor from the waiting is the resource that provides old aspirin hydrolyze and start come smell favor vinegar. IIRC, salicylic acid is much more toxic 보다 aspirin, therefore it’s unwise to take aspirin that has actually substantially decomposed. However, acetic acid has such a solid smell that also a little amount might be noticable. If a new, sealed bottle of aspirin smells of vinegar, it’s tho safe. The decomposition really starts once the pills space exposed come the atmosphere.