A 40-year-old member asked:
how long after taking plan b until the side effects start?
1 doctor answer • 1 doctor weighed in

Dr. Yash Khannaanswered
Family Medicine 57 years experience
Within 24 hours: Some side effects may start as early as 1 hour like vomiting and headache, and allergic reaction to the medicine and others may come within 24 hours and mestrual changes if any at next period
but not every one who takes Plan B gets the all or some of the side effects.
5.3k viewsAnswered >2 years ago
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Similar questions
A 47-year-old member asked:
Is Plan B safe?
2 doctor answers • 13 doctors weighed in

Dr. Dennis Higginbothamanswered
Obstetrics and Gynecology 30 years experience
Yes: Plan b is safe and effective - it works over 85% of the time if used within 72 hours (3 days) of unprotected sex and about 80% if used within 120 hours (5 days). There are few complications, but there are side effects occasionally, like nausea and headache.
6.1k viewsReviewed >2 years ago
A 31-year-old member asked:
Could you describe how do you use plan b?
2 doctor answers • 6 doctors weighed in

Dr. Meena Khandelwalanswered
Obstetrics and Gynecology 35 years experience
Just take the 1 pill: Soon after unprotected sex, take the 1 pill. Do not use this as the method of birth control - it is only for emergency in case of an oopsy! try to use condoms or birth control pills or iud or injectables etc.
5.5k viewsReviewed >2 years ago
A member asked:
Is it bad to take Plan B once in awhile?
1 doctor answer • 1 doctor weighed in

Dr. Heidi Fowleranswered
Psychiatry 25 years experience
It is far better: to use a consistent form of birth control than to use emergency contraception repeatedly.
670 viewsAnswered >2 years ago
A 18-year-old female asked:
How long you should wait to take plan b?
2 doctor answers • 2 doctors weighed in

Dr. Meena Khandelwalanswered
Obstetrics and Gynecology 35 years experience
As soon as possible: If you do not want to get pregnant, take it as soon as possible after unprotected sex but definitely within 3days or is useless.
5.5k viewsAnswered >2 years ago
Edgewater, NJ
A 18-year-old male asked:
What medicines should I not be taking in order to take plan b?
1 doctor answer • 3 doctors weighed in

Dr. Heidi Fowleranswered
Psychiatry 25 years experience
Agree w Dr. Collins: No absolute contraindications. Plan B One-Step is up to 89 % effective when taken within 72 hours (3 days) after unprotected sex. It can reduce chance of pregnancy by up to 95% if used within 24 hours. It continues to reduce the risk of pregnancy up to 120 hours (5 days) after unprotected sex, but is less effective as time passes.
667 viewsReviewed >2 years ago
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Last updated Jun 30, 2014
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