There is no clear clinical advice on whether ondansetron should be taken before or after meals. It is mostly used for the treatment of vomiting symptoms caused by radiotherapy, and has an antiemetic effect.
Whether to take ondansetron before or after meals can be chosen according to the actual situation. If it is used to relieve vomiting symptoms after chemotherapy, it can be taken before or after chemotherapy; if it is used for vomiting caused by radiotherapy, it can be taken before radiotherapy; if it is used to prevent nausea and vomiting symptoms after surgery, it can be taken before anesthesia.
Ondansetron may cause adverse reactions such as headache, abdominal discomfort, constipation, dry mouth, rash, bronchial asthma or allergic reactions, and transient asymptomatic transaminase increase.
Ondansetron needs to be taken under the supervision of a physician and should not be used blindly on its own.