A mouth full of irritated swollen gums apparently. Hopefully the NBOMe's are not going to put people in anaphylactic shocks or something. Like I said the 2C-X series seem to be able to do something curious immunologically and the NBOMe's are far more potent. Considering afaik this whole phenomenon has not yet been elucidated this could mean unpredictable things happening to your immune system.
That said, 2C-B is one that I've heard produce a bunch of mucus (and some other psychedelics even a purge of white sputum but that were tryptamines if I am not mistaken), and we have not yet heard of any sign that the halogenated NBOMe's are harmful in freaky ways (besides some adrenergic reactions). Right?......