Antihistamines are drugs which treat allergic rhinitis and other allergies. Typically people take antihistamines as an inexpensive, generic, over-the-counter drug that can provide relief from nasal congestion, sneezing, or hives caused by pollen, dust mites, or animal allergy with few side effects.
Explanation: It is a thing for people to intervene when debates, etc get too heated or tend to stray. An example of intervening would be trying to get people back on topic or trying to settle down a heated debate, discussion, etc.