My Husband Is 88 Years Old With A Heart Condition.

My husband is 88 years old with a heart condition. He is caughing a lot, but no fever. He has been taking Mucinexx DM for the caugh , but it doesn't seem to help a lot. Can he takeTesslon ? He has some but I don't know if hr should take it or not as I had it left over from my prescription not too long ago. He has taken Claritin for his runny nbose and it helps a lot. Thanks,