What are the side effects of the 9-valent human papillomavirus vaccine?

Generally, after receiving the 9-valent human papillomavirus (HPV) vaccine, possible side effects mainly include local reactions at the injection site, mild systemic discomfort, gastrointestinal symptoms, allergic reactions, and muscle or joint pain. A detailed explanation is as follows:

1. Local reactions at the injection site: This is a relatively common side effect. Redness, swelling, pain, hard lumps, or itching may occur at the injection site. These reactions are usually caused by irritation of local tissues by vaccine components and generally subside within 1-3 days after vaccination, requiring no special treatment.

2. Mild systemic discomfort: Some vaccine recipients may experience mild systemic symptoms such as low-grade fever, fatigue, or dizziness. These symptoms are typically transient and represent a normal immune response of the body to the vaccine. Symptoms usually resolve on their own with adequate rest.

3. Gastrointestinal symptoms: A small number of vaccine recipients may develop mild gastrointestinal symptoms such as nausea, vomiting, diarrhea, or abdominal pain. These symptoms are usually mild and short-lived. A bland diet and appropriate hydration can help alleviate them.

4. Allergic reactions: Very rarely, some individuals may experience allergic reactions, such as rashes or hives. In severe cases, symptoms may include difficulty breathing or facial swelling. Although such reactions are rare, prompt medical attention is required. It is recommended to remain under medical observation for 30 minutes after vaccination.

5. Muscle and joint pain: Some vaccine recipients may experience soreness in the arm where the injection was given or mild joint pain throughout the body. These symptoms typically resolve spontaneously within a few days. Avoiding strenuous exercise and getting adequate rest can help alleviate discomfort.

Prior to vaccination, individuals should truthfully inform healthcare providers of their health status. After vaccination, follow the guidance of medical staff. If severe or persistent adverse reactions occur, timely communication with the vaccination center is advised.