Doxylamine Succinate is an antihistamine that blocks Histamine (H1) receptor. It can cross the blood brain barrier and has a high affinity for H1 receptors in the brain that blocks H1 receptors. It also decreases the action of histamine at the H1 receptor by inhibiting both vestibular system & Muscarinic receptor. It affects the vestibular system & decreases the stimulation of the vomiting center. Its muscarinic receptor inhibition may also play a role in antihistamine antiemetic activity. Pyridoxine Hydrochloride is a vitamin B6 analog. It is used to prevent nausea and vomiting due to its antiemetic properties.