Caustic agent in drink I was served a coca cola around 8 PM and immediately felt a burning sensation in my mouth and throat. I spit it out back into my cup and my mouth tasted like the smell of the cleaner they had used to clean our table. Then I smelled the beverage, which had a strong chemical smell. My throat is still irritated and swollen, but the burning has subsided after gargling tons of water and spitting it out.