Receding gums are caused by poor intestinal health, which is in turn related to poor liver and gallbladder health.
You write:
"I've been on heavy medication for 7 years-don't know if that is something to do with it."
I have no idea on what heavy medication you have been for 7 years, but you can bet those heavy medications have affected both your liver, gallbladder and the health of your intestines.
You need Liver Flushing and a very healthy Diet and a very healthy lifestyle, if you are to stop receding gums.
Trying to treat receding gums with some oral remedies is of no effect as it does not address the cause ... damaged intestines, damaged intestinal flora.