Side Effects and Tolerability

When taken as directed, Plan B One-Step® is generally safe for women. Some women will have side effects that include:

  • Menstrual changes
  • Nausea
  • Lower stomach (abdominal) pain
  • Tiredness
  • Headache
  • Dizziness
  • Breast tenderness
  • Vomiting

Some women taking Plan B One-Step® will have menstrual changes such as spotting or bleeding before their next period. Some women may have a heavier or lighter next period, or a period that arrives earlier or later than usual. If the patient's period is more than a week late, she may be pregnant and should be tested.

If the patient has severe abdominal pain, she may have an ectopic pregnancy, and should get immediate medical attention.

If the patient vomits within 2 hours of taking the Plan B One-Step® tablet, the patient should immediately contact a healthcare provider to find out if she should repeat the dose. It is up to the healthcare provider's clinical judgment whether or not the patient should repeat the one-tablet dose.

Plan B One-Step® does not protect against HIV/AIDS or other STIs.