Ketotifen making me feel foggy, is it common?

started on ketotifen for the dermographism w/ chronic hives, and man i felt kinda like a zombie for about 2 weeks… it wasn’t just tired though, more like my brain was coated in cotton wool… i’m trying to figure out if this level of fogging is just part of starting an H1 blocker or if the MCAS fatigue I get from flares is somehow different? i mean, does the type of brain fuzz change when it’s drug related vs.

genuinely immune stuff?