Benadryl (diphenhydramine) is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose. Benadryl is used to treat sneezing, runny nose, watery eyes, hives, skin rash, itching, and other cold or allergy symptoms. Benadryl is also used to treat motion sickness, to induce sleep, and to treat certain symptoms of Parkinson's disease.
Diabetic headaches have several causes. Photo Credit Jupiterimages/Comstock/Getty Images. Diabetes impairs your body's ability to produce or use insulin, which regulates blood glucose levels and generates energy. In type I diabetes, the pancreas does not produce insulin. Without insulin, too much sugar remains in the blood and becomes toxic, leading to fatigue, neuropathy, headaches, blindness and death if left untreated.
Diabetes can harm the eyes. It can damage the small blood vessels in the retina, the back part of your eye. This condition is called diabetic retinopathy. Diabetes also increases the chance of having glaucoma, cataracts, and other eye problems. Diabetic retinopathy is caused by damage from diabetes to blood vessels of the retina. The retina is the layer of tissue at the back of the inner eye. It changes light and images that enter the eye into nerve signals, which are sent to the brain. Diabetic retinopathy is a main cause of decreased vision or blindness in Americans 20 to 74 years old.