However, PEP is not guaranteed to work, and the medicines that are used cause some unpleasant side effects, such as nausea , vomiting, diarrhoea , and headaches.

• 不过，PEP的是不能保证工作，以及药品使用造成一些不愉快的副作用，如恶心，呕吐，腹泻和头痛。