sudden flareup

last week over a period of around 6 days i consumed 2 bottles of cough mixture for a mild throat infection and dry tickly cough well towards the end of the week an over a 2 NIGHT spell i experienced a really severe flare up covering about 4 inches by 2 inches on my wrist and the back of my hand i have had very mild psoriasis barely noticeable since 1995 but never have i had any thing quite like this what i would like to ask is could there be any connection between the cough mixture and the sudden severe flareup thanks