Doxylamine is a medication used to manage and treat nausea and vomiting of pregnancy (NVP), allergic rhinitis, and insomnia. It is in the first-generation histamine receptor H1 antagonist class of medications. In the USA, it is available as an over-the-counter medication. This activity reviews the indications, action, and contraindications for doxylamine as a valuable agent in managing nausea and vomiting of pregnancy (NVP), allergic rhinitis, and insomnia.