I'm planning on sealing mine in half-gallon or gallon mason jars with a large desiccant pack on the bottom and an overkill amount of oxygen absorbers on the top. I'm assuming the O2 absorbers will do their thing before the desiccant pack steals the moisture needed to rust the iron in the O2 absorbers. I'm not planning on opening the jars until I need the meds in an emergency, so I'm guessing they will last a long time that way.
Remember, keeping the drugs in the freezer is an important part of the storage plan. The labs keep their drugs way way colder than 30 degrees. Is it safe to keep mason jars that cold? I have never used them. I'd be worried they would lose their seal.