Adverse effects and warnings
According to safety studies performed with the hepatitis A vaccine, the most common adverse events are:
- Tenderness in the site of injection
- Erythema or redness in the area of injection, usually with swelling and warmth
- In some patients, irritability
Other relatively common side effects include:
- Anorexia (loss of appetite)
- Headaches and drowsiness
- Fever of 100.4 ºF or higher
We also have a list of uncommon side effects that show up in less than 10% of patients:
- An upper respiratory infection
- An infection in the middle ear (otitis media)
- Diarrhea
- Rhinorrhea (nasal mucus) and sometimes cough
- Skin rashes
- Fatigue or muscle weakness
- Vomiting
Very rare side effects that show up in less than 1% of patients include:
- Photophobia
- Hematoma
- Vertigo
The only absolute contraindication to the administration of hepatitis A immunizations is a documented hypersensitivity to any vaccine component. It is also important to note that the prefilled syringes are in contact with natural rubber latex, which sometimes causes an allergic reaction.
The pregnancy category of the hepatitis A vaccine is C. This means that this vaccine should be used with caution in pregnant women. It is only used when the benefits outweigh the risk. There are no studies in humans, but animal studies show some risks to administering the vaccine to pregnant women. However, there is no direct evidence of human fetal risk.
