How should antiemetics be scheduled for a client undergoing radiotherapy known to cause severe nausea?

The best approach for scheduling antiemetics for a client undergoing radiotherapy that is expected to induce severe nausea is to administer the medication 30-60 minutes before treatment. This preemptive timing allows the antiemetic to be at peak effectiveness when the emetic stimuli begin, thereby significantly reducing the likelihood of nausea and vomiting associated with the therapy.

Administering antiemetics at this time allows the medications to work on the central vomiting center in the brain and the gastrointestinal tract to help prevent the nausea that can arise from radiotherapy. This proactive strategy is preferred over waiting for symptoms to occur or providing treatment post-therapy, as it is generally more effective in managing pre-treatment nausea.

In contrast, waiting until nausea begins or administering medication only once daily may not provide adequate control when the potential for acute nausea is highest, which tends to occur immediately following radiotherapy sessions. Thus, timing is crucial for optimal effectiveness in this scenario.