In the United Kingdom, Benadryl products contain either the second-generation non-sedating antihistamine acrivastine or the long acting antihistamine cetirizine . Benadryl products are marketed in Australia and New Zealand by Johnson & Johnson Pacific. Each 5 mL of Benadryl Chesty Cough & Nasal Congestion contains 100 mg of Guaifenesin and 30 mg of pseudoephedrine hydrochloride as the active ingredients.