Is it safe for a 15 year old to take emergency contraception? how long do the side effects usually last? how effective are these pills?

Safe, effective for: Safe for OCCASIONAL use. EC pills are used after sex to lower the chance of pregnancy by about 70-80%. EC is a high dose of birth control. Abnormal bleeding or spotting is a common side effect. Nausea, abdominal pain or cramping, and fatigue may occur, but symptoms resolve in a day or two as the drug leaves the body soon. Women may also get breast tenderness, headache, dizziness, or vomiting.