Can you smoke marijuana while taking 250mg terbinafine?

Hard to say: Since consumption of marijuana remains illegal on a federal level there is not much data published about it's use while taking other medications. No interactions are listed with readily available interaction lists. For that reason we cannot say.

Yes, however...: There is no known adverse interaction between marijuana and terbinafine, though if using recreationally I advise moderation and to not use it daily. Also, much marijuana is sprayed with pesticides or can have other toxins so be careful of your source; if you can it organically-grown that's always the best choice. Since it's not yet legal in Georgia (which is ridiculous) please be cautious.

Not a good idea.: The THC in marijuana messes with the user's brain, especially so in college students and high school students, because their brain cells are younger than old adult brains and thus are still doing lots of important new connections. THC in adolescents can affect attention, memory, visual processing, full-scale IQ and verbal IQ. With problems in these brain functions, life just wouldn't be the same.