Havrix (Hepatitis A Virus (Inactivated), Aluminium Hydroxide)

Havrix is indicated for the prevention of hepatitis A infection in individuals who are at risk of exposure.

• Adults and children aged 12 months and older who require hepatitis A prophylaxis.
• Travelers to regions where hepatitis A is endemic or where outbreaks have occurred.
• Persons with occupational exposure to hepatitis A virus, such as laboratory workers.
• Individuals with chronic liver disease who need additional protection against hepatitis A.
• Close contacts of patients with confirmed hepatitis A infection.

The safety profile of Havrix includes both common, mild reactions and rare, serious adverse events.

Common

• Mild pain, redness, or swelling at the injection site that usually resolves within a few days.
• Low‑grade fever lasting 24‑48 hours after vaccination.
• Headache that is transient and improves without medication.
• Fatigue or general malaise that may last one to two days.

Serious

• Severe allergic reaction (anaphylaxis) presenting with difficulty breathing, hives, or swelling of the face and throat.
• Guillain‑Barré syndrome, a rare neurological disorder that can develop weeks after vaccination.
• Persistent high fever that continues beyond 48 hours and is not responsive to antipyretics.
• Seizures (rare) occurring shortly after immunization.

Before administering Havrix, healthcare providers should consider several precautionary measures to ensure safe use.

• Avoid vaccinating individuals with a known severe allergy to any vaccine component, including aluminium hydroxide.
• Postpone vaccination in persons with an acute moderate or severe illness until they recover.
• Use caution in patients who have previously experienced hypersensitivity reactions to other vaccines.
• Assess the need for vaccination in individuals with chronic liver disease, as they may benefit from protection.
• Consider deferring the vaccine in pregnant or breastfeeding women until a risk‑benefit evaluation is completed.
• Observe the injection site for at least 15 minutes after administration to detect immediate allergic reactions.

Havrix generally has a low potential for drug interactions, but certain situations warrant attention.

Avoid

• Do not co‑administer with other live vaccines in the same injection site, as it may affect immune response.
• Avoid simultaneous administration with immunoglobulin products intended for passive immunization against hepatitis A, which can interfere with vaccine efficacy.

Use with caution

• Concomitant use of immunosuppressive therapy (e.g., corticosteroids, chemotherapy) may reduce antibody response; monitor serology if needed.
• Patients receiving blood products or plasma derivatives should be evaluated for timing relative to vaccination.
• Individuals on antipyretic or analgesic medication may experience masked fever; assess clinical status accordingly.