What is Mylan 447 for?

If you mean pills, Mylan is not a specific drug. Mylan Pharmaceuticals is an American company that manufactures a great number of different drugs, mostly generics for popular brands. Mylan pills and capsules are often indexed with the Word "MYLAN" and a number, but all of them are different. You have to know the number on the index to find out what sort of medication you have and what it may be used for. For example, when the pill is indexed "MYLAN 216", it is Furosemide (generic for Lasix) - a diuretic that helps to remove excessive water from the system through urinary tracts. If the pill is indexed "MYLAN 451", it is Naproxen (generic Naprosyn), an anti-inflammatory drug. If you have a capsule indexed "MYLAN 1700", it isNitrofurantoin, an antibiotic. And so on...