Why do I spit foam from my mouth?
Your first concern may be that you’re sick, that you have rabies, that’s almost definitely not the case. We were always taught in school to stay away from animals that are foaming at the mouth, they might have rabies. I used to think that foaming at the mouth was a symptom of rabies, it turns out it was more a symptom of anger, which is a symptom of rabies.
Saliva is a fairly thick liquid. When dogs get angry they bark and drool (as usual) and the saliva in their mouth gets churned around and air gets into it. They don’t swallow, they don’t spit, they just let that saliva sit in their mouth as they bark and it gets foamy.
The foam in your mouth is nothing more than air trapped in the liquid, little tiny bubbles of air. Water is so thin that air bubbles usually just rise to the surface and pop, salt water can get foamy when it’s tossed around because the air bubbles have a tougher time breaking through the thicker water. Your saliva is much like that, the air bubbles cannot quite break the surface area of your saliva, they are trapped so to speak. These air bubbles do manage to break down into smaller and smaller bubbles until you get a foam.
There are a few reasons I can think of to explain why you spit foam. Firstly there are probably medical conditions other than rabies that you may have that I’m unaware of and you should always consult your doctor on such things. However, if you talk a lot without pausing and without swallowing the saliva that’s in your mouth, you’ll get some foam forming. Then when you continue talking you’ll spit that foam at whoever you’re talking to. You may not be drinking enough water, if your mouth gets dry the saliva gets thicker and the amount of foam will increase. So if you drink more water, talk less, or swallow more often you’ll probably see a reduction in the amount of foam your mouth creates.