It is unknown if brake fluid can kill a tooth nerve but it can potentially KILL YOU while using it in an attempt to alleviate a toothache. Due to hazardous safety concerns, we highly recommend against using this home remedy for tooth pain relief.
There are much safer alternatives to try which don't come with the risk of imminent death. However, the safest and most effective way to get rid of tooth nerve pain is of course to see your dentist.
Without further ado, we will provide concrete proof as to why brake fluid is so dangerous. Hopefully that'll convince you to put this home remedy in the useless discard pile (along with gasoline) so it never sees the light of day ever again.
Brake fluid is unsafe for oral use
Regardless of break fluid's efficacy on deadening a tooth nerve, you shouldn't use it because it is unsafe for oral use. In fact, it is outright dangerous to put it in your mouth and if you wanted a reason why, it's because the manufacturer stated so.
As an example, we can take a look at Prestone's brake fluid safety data sheet to see what they say about oral use and its safety for it.
Key points in safety data sheet:
Swallowing it is harmful to your health.
Contact poison control or go to hospital emergency department for help.
There is a lethal dose of 1 ml/kg if ingested.
Side effects from swallowing it
The safety data sheet explicitly says that it is harmful if you swallow it. Below is a list of potential side effects from ingesting brake fluid according to Prestone.
Gastrointestinal disturbances - irritation and abdominal pain
Nausea and vomiting
Headache and dizziness
Decreased urine production
Liver or kidney damage
Can be lethal
If you do happen to swallow it whether it be intentionally or accidentally, you should contact poison control or go to a hospital immediately.
There are a lot of adverse effects from ingesting brake fluid but the most severe one would be potential death. According to Prestone, one of the ingredients, diethylene glycol has an estimated LETHAL DOSE of 1-1.2 ml/kg.
We looked up scientific studies to verify their claim and it turns out that it was true. According to a study in Clinical Toxicolgy, diethylene glycol (DEG) has been involved in a number of prominent mass poisonings spanning back to 1937.
Literally, massive amounts of people died from brake fluid ingestion...
The study had an estimate of 1 ml/kg of DEG as the lethal dose, which was similar to what Prestone claimed. Therefore, we'd have to say that the claims are indeed true.
Putting the lethal dose into perspective
Brake fluid having a lethal dose of 1 ml per kg is very potent. How potent you ask?
The average adult male in the US weighs 199.8 lbs (90.72 kg) so the lethal dose would be about 90 ml of brake fluid. If we convert that to ounces that would be about 3 oz.
Essentially, swallowing less than half a cup of brake fluid is enough to kill you. That is probably about as much as a mouthful of fluid when you're rinsing.
What we're trying to say is that rinsing with brake fluid in order to kill your toothache may potentially kill you instead. Although we suppose, that would actually get rid of your tooth pain but with severe lasting consequences.
Brake fluid is not effective for pain relief
Putting aside the fact that ingesting this automotive fluid can kill you, it is still ineffective at killing your tooth nerve pain. The reason is because the solution cannot penetrate through the tooth to reach the nerve and deaden it.
Teeth have two outer layers which insulate the nerve and prevent it from being in contact with the oral environment, including automotive fluids. Before your home remedy can reach it, it needs to make it past the enamel and the dentin.
What we're trying to say is that since this home remedy has no way of reaching your tooth's nerve, it will not be able to affect it.
If you're experiencing extreme tooth pain, the best way to kill the nerve is by visiting your dentist. Since the pulp is insulated by the layers of dentin and enamel, it prevents home remedies from affecting it.
However, your dentist is able to bypass these layers of protection by drilling through them and create a direct pathway to the nerve. After that, they can physically extirpate the nerve via root canal treatment and permanently kill it. In other words, you'll get long lasting pain relief.
What if I am unable to make it to the dentist
We understand that not everyone will be able to get to the dentist immediately which is why there is a temporary method to lessen the tooth pain which is effective and not dangerous like brake fluid.
In lieu of the home remedies which we described earlier, you should try taking a specific pain killer, Advil Dual Action. This product has ibuprofen mixed with Tylenol all in one capsule.
The combination of the two pain medications can alleviate your tooth pain more effectively than when compared to taking them individually. Make sure you follow the instructions on the label properly and take the prescribed amount.
There has been no scientific studies done on whether or not brake fluid can kill a tooth nerve and provide you with pain relief. However, there has been studies done on deadly mass poisonings from automotive brake fluids. It is so dangerous that a mere 3 oz of it can kill an average adult male.
Due to its dangerous side effects and intended use solely for cars, we recommend against using this home remedy for a toothache. If you're having an unbearable toothache, you should get emergency dental treatment with a dentist instead of trying home remedies.