Final answer:
Antiemetic antihistamines effectively treat nausea and vomiting by binding to H1 receptors in the brain, preventing histamine actions that cause gastrointestinal discomfort. They also reduce allergy symptoms by preventing mast cell release or production of histamines. Dimenhydrinate (Dramamine®) is a common example of an antihistamine used for motion sickness.
Step-by-step explanation:
Antiemetic antihistamines work by inhibiting the action of histamine at the H1 receptors, which are located in the brain and responsible for causing nausea and vomiting. When antihistamines bind to these receptors, they prevent the histamines that have been released by mast cells from stimulating the itching and swelling of body tissues, which includes the actions causing gastrointestinal discomfort such as nausea. Furthermore, antihistamines also prevent mast cells from releasing or producing more histamines, contributing to the reduction of symptoms related to allergies and motion sickness. One example of an antihistamine that is commonly used for its antiemetic properties is dimenhydrinate (Dramamine®).
A consultation with a medical professional is recommended for those considering antihistamines for long-term use, as chronic allergies could lead to more serious conditions such as asthma, sinusitis, and lower respiratory tract infections that might not be treated effectively by over-the-counter antihistamines.
While scopolamine is another drug used to treat motion sickness via a transdermal patch, some may prefer the use of antihistamines like dimenhydrinate as an alternative due to concerns about scopolamine's potential side effects at higher doses.