How quickly does anti-sickness medication relieve nausea and vomiting from cancer treatment?

Some anti-sickness medicines are given before cancer treatment to prevent nausea; others are used when symptoms begin or on a regular schedule. They work through different chemical signals involved in nausea and vomiting, so a combination may be prescribed.

Nausea can begin during treatment or later, and may be worsened by dehydration, constipation, pain, anxiety, infection, or certain medicines. If one medicine does not control symptoms, the team can review the cause and change the plan.

Take the medicine at the prescribed time rather than waiting until vomiting is severe, unless your clinician gave different instructions. Sip fluids as tolerated, try small bland meals, and keep a record of doses, vomiting, and fluid intake.

Tell the oncology team if nausea continues, tablets cannot be kept down, or side effects such as marked sleepiness, constipation, dizziness, or restlessness appear. Another form or combination may be easier to use.

Contact the treatment team promptly for repeated vomiting, inability to keep fluids or medicines down, very little urine, worsening weakness, confusion, severe abdominal pain, or blood in vomit. Follow the team’s emergency instructions if symptoms escalate.

When should I take each anti-sickness medicine? Which symptoms require a call? What should I do if I vomit after a dose? Could constipation, pain, or another medicine be making the nausea worse?