Final answer:
Ondansetron, commonly known as Zofran, is a dopamine antagonist commonly used as an antiemetic. It is effective in preventing nausea and vomiting related to cancer treatments and surgery. Other options like scopolamine patches and antihistamines like dimenhydrinate are also available for treating motion sickness.
Step-by-step explanation:
The dopamine antagonist often used as an antiemetic is ondansetron, commonly known by the brand name Zofran. This medication is used to prevent nausea and vomiting specifically associated with cancer chemotherapy, radiation therapy, or surgery. Ondansetron works by blocking the effects of chemical messengers in the body that can trigger nausea and vomiting.
There are other autonomic or antiemetic drugs available, such as the transdermal scopolamine patch, which is also effective in treating motion sickness. For those who prefer alternative options, antihistamines like dimenhydrinate (Dramamine®) are available too. Psychoactive drugs, including antiemetic options like ondansetron, act as either agonists or antagonists on specific neurotransmitter systems in the body, directly affecting neurotransmitter activities like those of dopamine.