What are the side effects of Oseltamivir?
Mar 19, 2025
Source: Cainiu Health
Dr. Yang Ziqi
Introduction
Under normal circumstances, oseltamivir is available in dosage forms such as capsules and granules. Its side effects include nausea, vomiting, abdominal pain, diarrhea, headache, dizziness, allergic reactions, and psychiatric abnormalities. During oseltamivir treatment, it is important to maintain a light diet and avoid spicy, greasy, and irritating foods to prevent increasing the gastrointestinal burden and inducing or exacerbating side effects such as nausea and vomiting.
Generally, oseltamivir is available in capsule and granule formulations. Its side effects include nausea and vomiting, abdominal pain and diarrhea, headache and dizziness, allergic reactions, and psychiatric disturbances. It is recommended to use the medication as directed by a physician. A detailed analysis is as follows:
1. Nausea and Vomiting
After oral administration, oseltamivir is rapidly absorbed in the gastrointestinal tract. Its components irritate the gastrointestinal mucosa and interfere with neural reflexes, causing smooth muscle spasms that lead to nausea. At the same time, it affects the secretion of digestive fluids and peristaltic rhythm, resulting in abnormal digestion and movement of food, which further causes vomiting, often occurring in the first few days of treatment.
2. Abdominal Pain and Diarrhea
The medication irritates the intestinal mucosa, disrupting normal intestinal motility and digestive function. The intestinal smooth muscle becomes stimulated and spasms, causing abdominal pain. Additionally, it alters the intestinal microecology, accelerates peristalsis, shortens food retention time, and reduces water absorption, leading to diarrhea characterized by increased frequency and loose stools.
3. Headache and Dizziness
Oseltamivir and its metabolites affect cerebral vascular regulation, altering the vasodilation and vasoconstriction status, which results in abnormal cerebral blood supply and headache. Simultaneously, it disrupts the balance of neurotransmitters in the central nervous system, affecting body balance and mental state, leading to dizziness.
4. Allergic Reaction
An individual's immune system identifies oseltamivir as a foreign antigen, triggering an immune response and releasing inflammatory mediators such as histamine. Histamine causes skin vasodilation and increased permeability, resulting in itching and rashes; severe cases may lead to angioedema affecting respiration.
5. Psychiatric Disturbances
Oseltamivir affects the neurotransmitter system. Particularly in children whose nervous systems are not fully developed, the drug disrupts the balance of neurotransmitters such as serotonin, affecting brain signal transmission and causing psychiatric abnormalities like hallucinations and anxiety.
During oseltamivir treatment, it is important to maintain a bland diet and avoid spicy, greasy, and irritating foods to prevent additional gastrointestinal burden and to avoid triggering or worsening nausea, vomiting, and other side effects.
