Bendaryl is not recommended to relieve cold symptoms and may have unpleasant side effects.
Benadryl® is just one trade name for the generic medication called diphenhydramine. Diphenhydramine is an antihistamine and is most commonly used as an allergy medication. Diphenhydramine, for example, may be suggested for an itchy rash, hives, or other mild skin rashes that itch. It can also be used for sneezing and watery eyes associated with seasonal allergies or allergies to cats, dogs, dust, or the like. Diphenhydramine is used appropriately to treat mild allergies only. It does not help in cases of anaphylaxis or life-threatening allergies.
Diphenhydramine, like other over-the-counter cold remedies, is not recommended for mild colds or upper respiratory infections. The watery eyes, runny nose, and congestion so common in the toddler years are caused by viruses and are unlikely to improve with an antihistamine. In addition, while some parents report that diphenhydramine helped their toddler sleep, many children have the opposite response and become agitated and awake. Overdoses are common and can cause extreme sleepiness, flushing, altered mental status, and fever.