I had the kenalog (triamcinolone) injection yesterday for allergic rhinnitis. Post nasal drip has not cleared. Should kenalog (triamcinolone) have worked by now?

Not likely. Steroids have a delayed onset of action due to the mechanism of how they work. If the allergy symptoms are significant, it may take even longer to see significant relief. In the U.S. The use of injectable steroids for the treatment of allergic rhinitis has fallen out of favor due to the risks and the availability of effective nose sprays. An allergist can provide a plan without those risks!