If you’re leaving the US, visit the Center for Disease Control (CDC) travel page before you do anything else. The CDC will tell you what immunizations you should have and other precautions you should take while at your destination. Some things, like hepatitis B shots, should be started months before you leave, so check the site early in the trip planning stage. When you know what you need, go to your local health department for the shots they can give you for free or cheap. Then visit a travel clinic or your regular doctor for any other shots or medications recommended by the CDC.