To answer your questions:
No, this is not on the list of drugs you can't fly on.
Frankly, there is no hard and fast reason you need an oral medication at this point, and you could use an anti yeast cream on your penis until your wife is better.
Make sure you have a prescription.
Men do not typically get yeast infections, and this is probably not
how your wife got this. Yeast is commonly in the environment. You have not stated that you have any symptoms at all. Typically there would be symptoms such as white spots, redness, dry rash, peeling, etc.
While is is OK for you and your wife to both be treated, if you really have a yeast infection, you need to see a urologist to make sure you don't have other problems.
I am a double board certified US doctor.
Find me anytime.
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