Which medication type is primarily used for controlling nausea?

Antiemetics are specifically designed to prevent or alleviate nausea and vomiting. They work by targeting the pathways in the brain and gastrointestinal tract that trigger these symptoms. This effectiveness makes them the primary medication type used for controlling nausea, whether it's due to motion sickness, chemotherapy, or post-operative effects.

Antihistamines, while they can have some effects on nausea related to motion sickness, are not primarily used for this purpose, but rather for allergic reactions and conditions like rhinitis. Antiseptics are agents intended to kill or inhibit the growth of microorganisms and have no role in controlling nausea. Antibiotics are used to treat bacterial infections and are not effective for managing nausea, which is often not caused by bacteria. Therefore, antiemetics are the correct choice when looking for medications specifically aimed at controlling nausea.