The Chlor-Trimeton Allergy 12 hour tablets work great to get rid of any nasal and chest congestion due to allergies. I feel like a lot of my congestion gets cleared out and my throat feels less itchy and irritated. I also find that my eyes are red and itchy anymore, and I was not sneezing at all throughout the day. I found that it got rid of all of my allergy symptoms, and I almost completely forgot that I even had allergies at all. I also find that I don't get drowsy from this allergy medicine. I know it has chlorpheneramne , which is a antihistamine. But it still didn't make me tried which is great because I can take it before a long day out and I won't feel sleepy. The chlorpheneramne is great too though because it helps with a sore throat, sneezing, watery eyes, and other allergy symptoms. Effectiveness It works great to get rid of and reduce the symptoms of allergies such as itchy throat and eyes, sneezing, runny nose, and more. I find that it gives me relief for the whole twelve hours if not longer. Ease of Use Its easy to use, and easy to swallow. They are great for people who have trouble or anxiety when it comes to swallowing pills because they are small. You only have to take one every 12 hours, which means you only have to take two a day. It makes it a lot easier because you don't have to remember to take the pills as often. Immediacy It does not have an immediate result. It takes about half an hour to kick in like most allergy medicines. If you were having a bad allergic reaction I don't think these would work as fast as you would want them to, but they are great for everyday allergy symptoms.