Histex-Ac is part of the Antihistamine / Opioid / Alpha-1 Agonist Combinations class and treats Nasal Congestion, Allergic Rhinitis, Cold Symptoms and other conditions. Antihistamine / opioid / alpha-1 agonist combinations are used to treat cough, nasal congestion, cold symptoms, and allergic rhinitis. They work by suppressing cough, relieving nasal congestion, and reducing cold symptoms. Histex-Ac is only available as a brand name drug. Get Histex-Ac for as low as $3.37, which is 81% off the average retail price of $17.88 for the most common version, by using a GoodRx coupon.