Question: are plan b pills effective?
Answer: The sooner you take plan B®, the more effective it is. It can prevent pregnancy if taken within 72 hours and preferably within 12 hours of unprotected sex. If you take it within 24 hours of unprotected sex, it is 95% effective. If you take it between 48 and 72 hours of unprotected sex, the efficacy rate is 61%.