At the beginning of taking emergency contraceptive pill, there may be nausea and vomiting in the stomach and other adverse reactions, at this time, you can take vitamin B6 to reduce these adverse reactions of the drug. But the main side effect of emergency contraceptive pill is to change the normal endocrine secretion, irregular vaginal bleeding or irregular menstruation, most of them can recover after 2-3 months, you can drink more water after taking the pill, which is good for the discharge of the drug. However, if you still have irregular vaginal bleeding or irregular menstruation after 2-3 months, you need to have a sex hormone test and use the medication according to the test results.