 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  vaccination schedule, which must be followed closely for best effectiveness. If you have an illness with fever at the time a vaccination is scheduled, your health care professional may choose to delay the injection until you are better. The dosage is based on your age. Different brands of hepatitis A vaccine are available and may be given differently. Make sure that you receive the same brand for each injection. For people who cannot get the vaccine before traveling or for whom the vaccine might not work, your health care professional may also give an injection of immune globulin. Immune globulin contains antibodies against the hepatitis A virus and will immediately help protect you from developing an infection. However, these antibodies last only a few months. For proper protection, it is important to carefully follow your vaccination schedule.The side effects of Havrix (PF) Intramuscular: Pain/redness/swelling at the injection site, fever, tiredness, headache, nausea, and loss of appetite may occur. If any of these effects last or get worse, tell your health care professional promptly. Rarely, some people have symptoms such as fainting, dizziness, vision changes, or ringing in the ears just after getting a vaccine injection. Tell your health care professional right away if you have any </s>