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 (4) | 9% |
Keny (Canada) on 09/19/2020: 
Why it works: It seals the wound.
It essentially dries the wound and causes it to contract, sealing the wound. You have to let it dry for it to be effective, this usually takes 2-3 minutes, but I'd give it more time to be sure (depends on your air).
It only hurts for the first 20-30 seconds, unlike other methods, and it seems to hurt less than salt/baking soda. It doesn't hurt long because the wound ends up sealed, so nothing that doesn't penetrate the seal will then hurt it!
If you use it while it is still SMALL it will hurt a lot less. I highly suggest using it when you see even the remote possibility of a canker sore. Let it dry, then rinse your mouth. Don't drink the alum, unless you're genetically allergic it probably won't kill you, but it's probably not good for you either.
The havoc of having an open wound in your mouth letting in all sorts of toxins and bacteria is likely way worse than any effect you can get from slight contact with alum, which is used as a pickling ingredient. The exception is if you're deadly allergic to alum. You can test by putting pin pricking your skin very lightly with a sterilized needle and putting a little alum to see how you react to it (that is how allergies are tested).
Miss T (NC ) on 08/31/2019:
Lauren (Ny) on 02/22/2018: 
Stacy (New Haven, Ct) on 07/21/2017:
Is there ANYTHING worse than trying to chew on one side of your mouth to avoid irritating a canker sore? Anything worse than avoiding your favorite foods/drinks as to not make the pain worse?? I love salty snacks, love my coffee and salt & vinegar chips, so I'm definitely prone to cankers sores every couple months.
My method is as follows:
Dip the end of a Q-tip into a bit of raw honey, just enough to coat the tip. Then dip the honey end into the alum. For this next part, I find it best to use one hand to hold my iPhone with the flashlight on to light up the inside of my mouth so I can see what I'm doing. With the other hand, place the Q-tip on the canker sore to coat it. Don't swallow for 1 minute. I do this in front of the bathroom sink because sometimes you do drool! Then I rinse my mouth with water, go to sleep, and by the morning it's painless and much smaller, if not completely gone.
Sometimes the after taste of the alum can leave your mouth feeling funny and dry, but drinking water definitely helps.
Thanks to to all who have suggested this amazing remedy! My mouth thanks you! :)
Twinkytoze (Brampton On) on 06/18/2017:
Patricia (Bucyrus, Mo) on 07/26/2016:
Josh (Weatherford) on 07/05/2015:
I set a timer on my phone for 2 minutes at first (I did this process twice for each sore), I never got to the point where I was on the verge of tears. My face got a little tingly, that was really it. But it's 10 minutes that I'm typing this after I went through this, and it still quite burns. But I'm only assuming that will go away within the next half hour(or maybe I missed a little tiny sore). After the first sore was taken care of, I got a large glob of it, and stuck it right in the center of alllllll of the sores. Yup. It hurt. But remember this when I say, you will never be able to get rid of a canker sore without pain, unless anesthesia is involved. I then set a timer for 2 and a half minutes, and waited it out. The sores definitely feel a little bit different when I touch around them with my tongue. They didn't burn AT ALL right when I rinsed with water, but only started burning again about a minute after. So that must be the side effects of the powder settling in deep in the sore. Which I also assume is a good thing? Kill that sore, alum. Kill it.
If you have any questions, feel free to ask away. I plan on doing this again tomorrow morning if the pain is still there (which I assume it will be, knowing my luck). So far, alum works!
Joecool025 (Sacramento, California) on 03/24/2015:
Bought a 2 ounce jar from the local grocer for about $5, which is more than enough. I bet 1/4 ounce would be plenty.
Over the bathroom sink, wet a q-tip, and dip it in the alum powder, roll it around to get a good amount on it. Then locate your canker sore and press and hold it on there real well. Time out 2 1/2 minutes on your watch or phone, then wet the other side of the q-tip, reapply, and repeat for another 2 1/2 minutes. Afterwards, rinse out that side of the mouth really well.
This stuff stings, and tastes bad. Try not to taste it with your tongue, and try not to swallow, just let the drool come out of your mouth down into the sink. It's not the most pleasant 5 minutes I've ever spent, but it really helped attack the sore, and minimized it, and dropped the pain down to about a 1 or 0 in 2 days.
I did this process twice a day for 2 days, and I am canker sore free!
Andrea (Des Moines, Ia) on 01/29/2015:
Cb (Ny, US) on 10/23/2014:
Buy some Alum (a pickling agent, should be able to find it in the spice aisle) and some mouth wash (I don't think it matters but I used a antiseptic tartar control one). Using your finger or a cotton swab dab some (not much, maybe a pinch) of alum onto the muceole and leave it alone as long as you can keeping the area dry by holding your lip (or wherever) out of the wetness of your mouth. I did for a about 20 mins - then wash it out carefully. WARNING - alum does not taste good and will feel strange in your mouth. Then use the mouth wash. The alum should "dry up" the muceole and the mouth wash will keep it from getting infected or bigger.
The next day (I did the first time at night) I noticed where I had placed the alum had dried the skin, much of my mouth was dry with peeling skin (not as bad as it sounds). I repeated this process three times within a six hour period the day after I started the remedy. I recommend starting on a weekend so you have time to do this. At this point I could see the white spot within the muceole (salivary gland) which is a good sign. After that I used mouth wash consistently for three days and my muceole healed and completely went away. It's now been a month without it coming back. Hope this helps someone out there!
