Medically reviewed by Alan Lucks | MD, Alan Lucks MDPC Private Practice - New York on January 23rd, 2026.
• Prevents pregnancy when taken within 72 hours of unprotected sex • Available over-the-counter for all ages and genders • Reduces pregnancy risk by 75-89% when used correctly • Does not protect against sexually transmitted infections
Emergency contraception is a critical reproductive health option for individuals seeking to prevent unintended pregnancy. The Plan B morning-after pill provides a safe, accessible method for reducing pregnancy risk after unprotected sexual activity or contraceptive failure.
Plan B contains levonorgestrel, a synthetic hormone that primarily works by delaying or preventing ovulation. Unlike abortion medications, Plan B prevents fertilization from occurring and does not terminate an existing pregnancy. If fertilization has already happened, the medication will not be effective.
The medication works through multiple mechanisms to reduce pregnancy risk. Primarily, it delays the release of an egg from the ovary, preventing potential fertilization. If ovulation has already occurred, Plan B can also thicken cervical mucus, making it more difficult for sperm to reach an egg.
Timing is crucial when taking emergency contraception. The effectiveness dramatically decreases with each passing day after unprotected sex. Within the first 24 hours, Plan B can be up to 95% effective, but this rate drops to approximately 89% by day three and continues to decline.
Most Plan B packages contain a single tablet that should be taken orally as soon as possible after unprotected intercourse. Refilling a prescription is not necessary, as Plan B is a one-time emergency contraception method.
Important considerations for use include:
Take within 5 days (120 hours) of unprotected sex
Effectiveness decreases with time
One tablet is typically sufficient
No prescription required
While generally safe, Plan B can cause temporary side effects. Common experiences include:
Slight changes in menstrual cycle
Mild nausea
Headaches
Breast tenderness
Potential slight dizziness
Cramping
If vomiting occurs within two hours of taking the pill, you're taking a medication that may require a repeat dose. Consulting a healthcare provider can provide personalized guidance.
Brand |
Average Cost |
Availability |
|---|---|---|
Plan B One-Step |
$40-$50 |
Over-the-counter |
Generic Options |
$11-$45 |
Pharmacies, online |
AfterPill |
$25 |
Online |
Certain medications can reduce Plan B's effectiveness. These include:
Rifampin antibiotics
Some HIV medications
Anti-seizure drugs
St. John's Wort supplements
Individuals weighing over 165 pounds may find reduced effectiveness with levonorgestrel-based emergency contraception.
No, Plan B prevents pregnancy and does not terminate an existing pregnancy.
Yes, Plan B is available to all genders without age restrictions.
While safe, it's not recommended as a regular contraception method. Consult a healthcare provider for ongoing birth control options.
No, Plan B only prevents pregnancy and does not protect against sexually transmitted infections.
No, Plan B is available over-the-counter without a prescription.
Emergency contraception provides an important reproductive health option. Care you can trust. Doctronic is clinically validated with 99% treatment plan alignment.
• Prevents pregnancy when taken within 72 hours of unprotected sex • Available over-the-counter for all ages and genders • Reduces pregnancy risk by 75-89% when used [...]
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