Zofran or Ondansetron treats nausea and vomiting. Originally it was introduced to counteract the gastrointestinal distress associated with cancer chemotherapy and radiation therapy. Zofran also prevents similar symptoms from developing during the post-operative period. Currently the medicine finds great utility as a treatment for gastroenteritis and morning sickness. Its use is considered off-label for these last two situations.

Zofran received FDA clearance in 1990 and became available as a much less expensive generic preparation in 2006. Doctors still prescribe Zofran more than 9 million times each year. The drug is on the World Health Organization’s List of Essential Medicines.

Many people with nausea and vomiting are unable to swallow a pill requiring additional liquid. Zofran not only is available as a standard tablet but also as an orally disintegrating tablet. This ODT is placed on the tip of the tongue and dissolves within 20 seconds. It is swallowed with the saliva without added fluid. In appropriate medical settings Zofran may be administered as an intramuscular or intravenous injection.

Side effects tend to be relatively mild and include headache, fatigue, itchiness and constipation. Rare instances of prolongation of the QT interval on the electrocardiogram may be associated with cardiac arrhythmias, palpitations or fainting episodes. When combined with drugs involving serotonin, Zofran may precipitate a syndrome manifest by tremor, muscle rigidity, agitation, delirium, flushing and seizures.

Several other members of the same drug family are available, however generic Zofran still retains its dominant position in the field.