My husband's doctor put him on Niacin before trying Lipator (sp?). What you are describing are symptoms his doctor told him to watch for (you may not be allergic to it afterall), he advised him to take an aspirin to counter attack those symptoms. My husband said the aspirin helped some, but he ended up going on a statin drug anyway.
My Dr. started me on 500mg of niaspan at night with one asprin for a month then increased to 1000mg. I have only experienced flushing one time when I forgot to take my pill at bedtime and took it first thing in the morning.