If odor is TRULY the issue here (and not maneuvering for control, as many posters suggest, and that might be the real hinge of it) a two-stage approach works well imo.
The charcoal canister is a good first step, but odor always leaks unless you have a fierce one-way airflow out of the dwelling.
The second stage is an ozone generator (like the Crystal Air brand) used to deodorize the household when needed. It's lovely because not only does it put paid to the redolence of medicinals ... you can use it for so much more, like freshening the air in winter, or forgiving the consequences of yesterday's onion ring orgy. Am i glad I have ozone as well as charcoal!
But you need to establish whether or not your gf is being practical, or if this is the skinny end of the ol' pussy whip. The tip goes in easy, but by the time the knurly handle approaches, I can guarantee some discomfort. Be aware, be wise, and find the balance between (often deserved) cynicism and the (rare but real) chance to make it all wonderful. cn