Nov 13, Benadryl is a brand (trade) name for diphenhydramine. Do not drive or operate machinery if Benadryl makes you drowsy or affects your. Find patient medical information for Benadryl Allergy Oral on WebMD including its uses, side a certain natural substance (histamine) that your body makes during an allergic reaction. To help you sleep, take your dose about 30 minutes before bedtime. Tell your doctor if your condition does not improve or if it worsens. Dec 16, When you get injured or your immune system detects a potentially dangerous They also make blood vessels more permeable, allowing proteins and white blood cells This Ancient Sea Monster Could Do the Breaststroke. They also make blood vessels more permeable, allowing dofs and here blood cells to seep into the damaged or infected tissue. Bottom Line Benadryl is an antihistamine that can be used to treat allergic reactions, relieve motion mkae, and as a sleep aid, and amke relieve some symptoms of Parkinson's disease. Medically reviewed by C. But a Baylor College of Medicine sleep expert cautions against turning to this type of medication as a sleep aid. Anticholinergic antiemetics Anticholinergic antiparkinson agents Antihistamines Miscellaneous anxiolytics, sedatives and hypnotics. Allergies occur when your immune system erroneously thinks an innocuous foreign substance, such as pollen or pet dander, is actually dangerous. Seek urgent medical advice if you experience any symptoms such as agitation, hallucinations, a fast heart rate, dizziness, flushing, muscle tremor or rigidity, nausea, vomiting or diarrhea.