Dimehydrinate belongs to the class of drugs known as antihistamines. Dimehydrinate is a second-generation antihistamine. It contains pyridoxine and doxylamine. Doxylamine, which is an antihistamine, blocks natural substances in the body that cause nausea and vomiting. Whereas, Pyridoxine is a vitamin that aids in controlling vomiting and nausea during pregnancy.