It is my favorite molecule mainly because it was invented by my grandfather, George Rieveschl, in 1943. I also like Benadryl because it is a very effective antihistamine that has no serious side effects- basically it just makes you tired. The drowsiness side effect may actually be a plus because many people take it to help them sleep. At the time he invented Benadryl, my grandfather was an organic chemist who was teaching organic chemistry as well as pursuing research on muscle relaxers. He had recently finished completing a doctorate in organic chemistry. During his research, he noted that one of the molecules he synthesized had a very interesting property: it was able to block receptors in capillaries that were acted on by histamine. He thoroughly documented all of his laboratory work and brought the drug to be tested at Parke-Davis Pharmaceutical Company. It was the first prescription antihistamine approved by the FDA in 1946, and the first one without any majorly harmful side effects. Benadryl is now an over the counter drug that is mainly used for treating allergic reactions. It prevents itching, inflammation, and other symptoms of allergic reactions. Aside from its use in alleviating allergic discomfort, Benadryl is often used to treat motion sickness, rashes, and Parkinson's disease symptoms. Benadryl can be taken orally or applied topically.