Doxylamine succinate is an antihistamine drug that relieves symptoms of upper-respiratory allergy and hay fever. It is an over-the-counter (OTC) or non-prescription medication that is used as an allergy medication.
Drowsiness and dry mouth/nose/throat have been reported. If side effects persist or worsen, contact your doctor or pharmacist promptly. A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.