Hi for the last week im having to scrub my tongue really hard to get rid of this black coating that keeps formong my husband says it could be some medication ive took but the only different thing ive took are colpermin for ibs but last week i had a itchy throat and actually fell to sleep with a strepsil on my tongue for ages in the night im wandering if that has caused some inbalance of the normal bacteria on my tongue like antibiotics can do in your stomache or does that sound silly x