DRUG CLASS AND MECHANISM: Diphenhydramine is an antihistamine used for treating allergic reactions. Histamine is released by the body during several types of allergic reactions and--to a lesser extent--during some viral infections, such as the common cold.
Symptoms Symptoms of lactose intolerance. The symptoms of lactose intolerance can occur after youâve eaten or drunk something that contains lactose. Symptoms of lactose intolerance may include: 1  feeling bloated. 2  pain or cramps in your tummy (abdomen). 3  diarrhoea. 4  wind. 5  feeling sick.
Lactose intolerance occurs when the small intestine does not make enough of an enzyme called lactase. Your body needs lactase to break down, or digest, lactose. Lactose intolerance most commonly runs in families, and symptoms usually develop during the teen or adult years. Most people with this type of lactose intolerance can eat some milk or dairy products without problems.