Do You Need To Retake Your Birth Control Pill When You Have Diarrhea?
In our latest question and answer, the pharmacist discusses what to do if you have diarrhea when taking oral birth control pills.
I am on Aubra 28 birth control pills for a month now and I am on my second pack. I had sexual intercourse at 2:30 PM without a condom on April 6, 2018. However, I never miss a pill and I took mine at 11:30 PM every day. But ten minutes later I had slight diarrhea once. Today I asked planned parenthood if I should take another birth control just in case. They said to do it just in case and keep taking regular birth control. I did it at 3 pm. I spoke to my university pharmacist and said it was a mistake and this wasn't necessary. Who is right here? I will not have sex for 7 days and use backup.
Sep 27, 2022- You do not need to retake your birth control pill if you have diarrhea lasting less than 24 hours, according to most health authorities including the CDC.
- If diarrhea continues for more than 48 hours, you should use backup contraception for 7 days after the diarrhea stops while continuing to take your pills as usual.
- Taking an extra birth control pill as a precaution will not harm you or lower your pregnancy protection, though it may cause mild side effects like nausea or spotting.
Answer
Recommendations for whether or not you need to take an additional birth control pill (or when to use backup contraception) when you have diarrhea are mixed. However, most health authorities, including the CDC in the United States and the United Kingdom National Health Service state that additional measures are only necessary if you have had diarrhea for over 24 hours.
Now, the prescribing information for most oral birth control products, such as Aubra, state the following:
"If you have diarrhea or if you take some medicines, including some antibiotics, your pills may not work as well"
This statement is fairly ambiguous in terms of what you should do if diarrhea occurs when taking birth control pills. Some birth control products do recommend that additional contraceptive measures should be taken in cases of severe diarrhea, due to altered absorption, but specific recommendations are lacking.
Recommendations
Several health authorities give recommendations for what to do if you have diarrhea and are taking birth control pills.
What Does The CDC Say?
The recommendations from the Centers for Disease Control are more specific than the product information for your birth control. They state:
- If you experience vomiting or diarrhea within 24-48 hours of taking your oral contraceptive, it is not necessary to re-dose with another pill nor is it necessary for emergency contraception. Continue to take your birth control as directed at the same time every day.
- If the vomiting or diarrhea continues for more than 48 hours, continue taking pills at your usual time and use backup contraception for 7 days after the vomiting and diarrhea have stopped.
- If the vomiting and/or diarrhea have continued for more than 48 hours and occurred in the last week of hormonal pills (days 15-21), omit the hormone-free pills of the current pack and start with the first week on a new pack. If you do not have a new pack of pills use backup contraception until the hormonal pills of a new pack have been taken for 7 consecutive days.
- Emergency contraception is considered an option if the vomiting or diarrhea has occurred for more than 48 hours within the first week of hormonal pills and unprotected sex has occurred within the previous 5 days.
The following graphic from the CDC shows the recommendations given above in a flow-chart format:

Source: Centers For Disease Control
It should be noted that Planned Parenthood provides the same advice as the CDC in regard to having diarrhea and whether or not to re-dose if you are taking birth control pills.
Other Health Authorities
The United Kingdom National Health Service is a little more conservative than the CDC.
They state that if you continue to have diarrhea for more than 24 hours, count each day with diarrhea as a day that you have missed your pill. If you follow these recommendations, be sure to follow the procedures for missed birth control pills as directed by your specific product.
The United Kingdom National Health Service also provides more conservative recommendations for vomiting.
They state:
- If you're sick (vomit) within 3 hours of taking a combined pill, or within 2 hours of taking a progestogen-only pill, you should take another pill straight away.
- Take your next pill at the usual time.
Additional Information
Having said all of the above, you can't really go wrong taking an additional dose of your birth control pill. Taking an extra dose as a precaution after vomiting or diarrhea may slightly increase the risk of nausea, headache, and spotting due to the excess hormones, but won't have any other effects. It will not lower the concentrations of hormones from your other birth control pills and you are still protected from pregnancy.
Lastly, your chances of getting pregnant are very low as you have taken your birth control around the same time every day, have not missed a dose, have taken an additional hormonal pill, and have taken emergency contraception. You may experience irregular menstruation and breast tenderness due to the extra hormones from the additional birth control pill and the emergency contraception.
In regard to 'who is right' in your situation, having only had one instance of diarrhea (less than 24 hours), you generally would not have to retake a dose of birth control pills.
Final Words
To summarize:
- Recommendations vary in regard to taking additional birth control doses when you have diarrhea.
- Most birth control products state that the efficacy of birth control pills may be affected if you have severe diarrhea.
- However, the CDC recommends no additional dosing unless diarrhea occurs for more than 48 hours. Planned Parenthood echoes this recommendation.
- Taking an additional birth control pill regardless will not put you more at risk for pregnancy, but you may experience some mild side effects.
References & sources
Glossary — Terms in This Answer
- Oral contraceptive
- A birth control pill taken by mouth that contains hormones to prevent pregnancy.
- Absorption
- The process by which the body takes in and processes a medication through the digestive system.
- Re-dose
- To take an additional dose of a medication after the original dose may not have been fully effective.
- Backup contraception
- An additional birth control method used alongside your primary contraceptive to reduce pregnancy risk.
- Emergency contraception
- A medication taken after unprotected sex to prevent pregnancy.
- Progestogen-only pill
- A birth control pill containing only the hormone progestin, without estrogen.
- Efficacy
- The ability of a medication to produce the desired effect or outcome.
- Hormonal pills
- The active pills in a birth control pack that contain pregnancy-preventing hormones.