[ELI5] Why is it sometimes not recommended to induce vommiting if you accidently swallow a dangerous substance?


For example some lighter fluids

In: Biology

Some fluid will burn your throat on the way up. That will cause greater problems run. And with a raw throat, stomach acid, and whatever else the fluid has to leach into you. That’s pretty bad mix

Some things will cause more damage to the esophagus coming back up. You either have pump it out or take something to counteract it first

Doctor here, and the other posters are correct in saying that the act of inducing vomiting can be more dangerous than the ingestion of the substance itself. Besides burning the lining of the esophagus, there is also a risk of esophageal tearing from excessive vomiting and subsequent bleeding from the tear (made worse from the already irritated tissue).

Many substances can be detoxified in a safer manner, with timely medical attention. It is better to contact your local emergency authorities (e.g. poison control / 911 in the United States) rather than guess yourself, as they can guide you specifically what to do in the event of exposure to toxic substances.

Let’s say you drank something corrosive like drain cleaner. It would severely damage – corrode – all the tissues on the way down. It you vomited it up, it would do the same thing to the already damaged tissue & make your situation worse.

The main component of stomach acid is hydrochloric acid, which is powerful stuff! So, our Stomach lining is designed to handle strong acids. It’s better to keep that drain cleaner in the stomach. The docs will suck it out orhave you drink stuff that absorbs the acid & reduces its damage the rest of the way down. It’s usually some nasty charcoal stuff.

Everyone’s mentioning the risk of damaging substances transiting the esophagus twice, which is true. But the other reason they give this instruction is the risk of aspiration into the lungs. All of these instructions assume access to modern medical assistance, BTW.

You’ll also see “don’t give activated charcoal,” for example, but not (always) because it doesn’t work. More like the experts know that “get your ass to a damn hospital” is like 100x better than “just eat a bunch of activated charcoal and expect that to be sufficient.” They don’t want people thinking they should go for plan B when plan A is within reach.

Another one is: if your kid drank the old antifreeze (the formulation that tasted sweet), they’d say “don’t give the kid vodka.” Because they really mean “don’t try to fix this at home – take him to the hospital!” But if there’s a natural disaster that’s blocked your access, hospital too far away, you’re in a country without medical support, zombies surround you, etc, then alcohol is, actually, the right treatment.

Hospital pharmacist here, in addition to the better alternatives such as neutralizer agents/suctioning, one of the primary purge inducers – syrup of ipecac was discontinued in 2010, in large part due to multiple studies that determined that purging was highly variable and risked more harm than good (esophageal damage, aspiration into lungs, etc. as mentioned by other posters).