It sounds like brushing irritates your pharynx... a lot... somehow.

I have a few ideas perhaps....

1. Brushing method -- If you brush your tongue and mouth in general (it's good hygiene to do so), you might be be:

---- brushing too far back
---- brushing too hard
---- accidentally touching the more delicate upper parts of the pharynx.

2. Toothpaste -- You might be reacting to your toothpaste. I find the strongly mentholated ones give me a heavier reaction. Try different quality brands and see if a milder-tasting one is easier on you. I personally used to use Crest over there. I think it tasted mildish, but I don't really remember the different tastes now of the US brands. We have mostly different brands here. Here I use Colgate Total (can't get Crest). I remember that I preferred Crest to Colgate over there. YMMV.

3. Chronic irritation due to reflux -- Do please talk to your doctor about the reflux and possibly a gastroscopy. You might only have the heartburn when it's worse -- ie. you might have the problem sometimes without obvious symtpoms. Chronic reflux irritates the pharynx and cause irritation all the way to the base of the tongue. If these tissues are chronically irritated, they will be muuch more reactive to any stimulus, including normal brushing, acceptable toothpaste, mouthwash, etc.

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I'm sure you're not the only person to whom this happens. I think the breaking out into a sweat is probably an anxiety reaction when the symptoms are bad, but the other symptoms all sound like irritation.

waves