Did you know that antibiotics could affect the menstrual cycle? Indeed, most of them can have an effect on menstrual periods, with some reporting delays. Find out more about the connections between antibiotics and the menstrual cycle below.
Your Regular Cycle
During the first 14 days of a 28-day menstrual cycle, your follicle will start to grow and kick-start the initial production of additional estrogen. It will start to make the endometrium lining thicker. When ovulation commences, the estrogen hormone will be joined by the progesterone hormone from the corpus luteum to make the endometrium mature and thicker.
How Antibiotics Affect the Normal Cycle
Antibiotics can interfere with your body’s mechanism, which secretes the human chorionic gonadotrophin hormone (hCG) and cause uterus shedding to delay your period. This will happen mainly because the available estrogen will be reduced to cause a change in your cycle for it to become irregular.
A study done in 1947 shows that Penicillin caused heavier bleeding, changes in pain and PMS symptoms and the start of the cycle itself, but they stated that they weren’t able to find any correlative information regarding that.
There are actually two ways antibiotics could affect the estrogen metabolism. Most antibiotics are metabolized in the liver, and when they are present, the metabolism rate of estrogen as well as progesterone will be affected. This can interfere with the estrogen supply that is in the blood and causes an irregularity of the menstrual cycle.
In order for the follicular phase of menstruation to occur, the estrogen is needed to stimulate the ovaries and thicken the uterine wall. Without this, ovulation doesn’t happen or it happens late, which obviously affects when your period will arrive.
Other Issues with Antibiotics
There are some antibiotics that will cause diarrhea-like symptoms when they interfere with the stomach flora.
Even though it’s supposed to kill the bad bacteria in the body, it also affects and kills the good bacteria as well, which is why some women report yeast infections as well after their use of antibiotics.
The entero-hepatic circulation will be affected and cause a reduction of estrogen levels in the blood. It’s becausegut bacteria that usually re-activates small amount of estrogen in intestine are no longer available [1].
When the estrogen levels change in the blood, your cycle will be affected low estrogen levels fail to stimulate pituitary release of hormones. Your body actually ovulates based on the pituitary gland’s ability to identify that sufficient estrogen is in the blood, and then cause LH surge which causes ovulation on 14th day of cycle. So antibiotic treatment can affect these delicate hormonal balances.
So your body doesn’t have enough estrogen to regulate normal menstrual cycle.
Another important point to note is that antibiotics change your body’s metabolic performance and the ability to sustain a steady hormone level.
Use the Second Form of Protection if you are Not Trying to Get Pregnant
Antibiotics can also affect the estrogen as well as progestin levels in oral contraceptive pills. Estrogen is actually an active ingredient in these pills and the antibiotics will affect how it’s metabolized in the body.
Rifampicin and Rifabutin are liver enzyme-inducing drugs and can clear the estrogens from blood at faster rate thereby reducing the contraceptive benefit anticipated from contraceptive pills.
You should get medical advice if you are taking antibiotics in the first seven days of a new pill packet and you engage in sexual intercourse in the last five to seven days. The antibiotics could disrupt the normal protection that the pills provide and cause you to get pregnant.
So if you are taking antibiotics, ensure that you are also protecting yourself as well if you are not looking to have another child right now.
Reasons other than antibiotics that affect your period
While antibiotics get a bad rap regarding the effect on the body and the menstrual cycle, there can be other potential issues and situations that can go on with the body during the time frame. When sick, antibiotics or not, the body is being stressed to the max.
It is trying to accommodate for being sick and the stress of still having to maintain a home, a job, children, a spouse (because you know, moms don’t take sick days). So take into consideration that it can be affected by the meds or by stress, weight loss or gain, usage of birth control, and PCOS or thyroid conditions.
How to Prevent Antibiotic Related Period Issues
One way to help balance your hormones while you are on antibiotics could be to switch up your diet while you are taking antibiotics (and after as well if you are looking to maintain a healthy balance).
In order to balance the estrogen levels, you can add some fish oil, vitamin D, and vitamin B to your diet as well as probiotics, which can help balance that gut bacteria in a beneficial way.
Plus you’ll want to get enough sleep (which helps so many bodily systems) and be stress free (see above).
In general, antibiotics can affect so many bodily systems. Know that they shouldn’t be something that you take on a regular basis because it can cause antibiotic resistance in the body.
Take them only if necessary and ensure that you take the proper precautions for preventing pregnancy and keeping your other systems in balance.
If your period is still late, however, take a test and be confident with the results. But if you are still concerned with what is going on, be sure to talk to your doctor if you need more information on the effects of antibiotics and menstrual cycle.
References
- Estrogen-gut microbiome axis: Physiological and clinical implications. https://www.ncbi.nlm.nih.gov/pubmed/28778332
Hi,
I took ciprofloxacin for two days and was getting too weak that I’ve to stop it, now my period came earlier than expected hope this won’t be any side effect because have I been trying to get pregnant for while now.
Hi there Bunmi, please take a pregnancy test to confirm if you might be pregnant. All the best.
I have been getting penicillin shots for tonsillitis since Monday. I’ve been on a pill and had unprotected sex last Friday, 2 days before starting taking penicillin. Do you think there is a chance of pregnancy (I haven’t had sex ever since) and should I expect a missed or late period this month?
Hi there Olivia, having unprotected sex does provide a risk for pregnancy, please take a pregnancy test to confirm if you might be pregnant or not.
Hi. I am 3 days delayed. I had a pulling out method at the end of the month of April. And also, on the 2nd week of May I took anti-biotics for 1 week prior to my expected period to treat swollen lymph nodes. I already did 2 tests, and it both came negative. I was never late until I took this treatment. Am I pregnant or it’s just the effect of anti-biotics? Looking forward to a positive feedback.
Hi there Letizia, anti-biotics over the years have been known to delay periods. This seems to be the case for you. It should show in a couple of days, all the best.
Hi, after Two Days of my menstrual cycle,I took ampiclox to prevent a pain on my finger. At midnight when I woke up, I observed my pant have soaked with a liver-like and thick Blood. It happens that when it’s Coming out double pad cannot hold it. This became severe that I was afraid to step out of the house. Now, the heavy flow have stop but I’m Still having an Irregular spotted discharge with pains for Like two weeks. What’s the cause, and how do I stop this blood spot discharge.
Hello there Nescyy, there might be quite a number of reasons why this has happened. I would advise however that you see your doctor as soon as you can.
Can a period’s timing be messed up for more months than the one that got messed up while taking antibiotics? I had to take two rounds of antibiotics in April and it through my period off by a week. Since I’ve been very regular, I figured it would go back to normal after that one month, but it hasn’t. This is my second period to be late.
Hello Mikkij611, yes this can happen and is normal with the taking of anti-biotics. All the best.
Hi I am expecting my period last Monday 8th of May but due to my sore throat and fever I have to take antibiotic. My period didn’t start and now I am delayed 4 days. I have pelvic pain on the right side and feel bloated. is this normal or am I pregnant? please help
Hello there Mary, taking anti-biotics has been known to throw off ones cycle, this happened and all should return to normalcy soon. All the best.
Hello there.
I had my period for around 10 days and it stopped for around 3 days. Then I start taking amoxicillin and started to bleed again. I accidentally skipped a dose yesterday and my bleeding stop.
Today in the morning I continued to take the antibiotic as per normal and found that my panty liner is covered with blood.
Is it the side effect of amoxicillin or is it just my period?
Should I be worried? PLEASE HELP D:
Hi there Samash, the taking of anti-biotics can interrupt/alter the regular flow of a period. This might or might not be the case for you. Observe how this progresses. All the best.
I took 4 tablets of phenoxymethylpenicillin a day for 6 days to treat tonsillitis, my last period ended February 28 and I started taking tablets at the end of march I still haven’t had my period yet , there is no chance of being pregnant
Hello X, not sure what your question is but if you think you might be pregnant then do not hesitate to take a pregnancy test.
Hi,I took Azithromycin 500mg for 3 days.I was supposed to get my period on april 25. and received all the normal signs but till now I have not gotten my period.I did a pregnancy test today and it came back negative.My period was regular and this is my first time that my period is getting delayed.Is this normal????
Hello Anns, the taking of this drug has been shown to alter a menstrual cycle. Kindly give it some more time. All the best.
Hi I’m taking antibiotic due to skin allergy on my face, the antibiotic is tetra and I took it since April 18, 2017. My period has a 30 day cycle. Should it be on April 21, 2017? Its been 5 days ago since my expected menstrual cycle. Is the antibiotic I took causing my delay? How many days delayed should it be?
I am hoping for your positive feedback.
Hi there Marlyn, yes the taking of antibiotic has been known to delay periods. If your period does not return in 3-5 days then take a pregnancy test. All the best.
I been taking penicillin for about 8 days ( today is my last day) I had got my period on the 21st for about two hours then it stopped. This have never happened to me before could the medicine be causing this ? Or could I be pregnant?
Hello there Shameka, this might not have been your period…if you keep having occurrence of this consistently then see your doctor who advised the taking of penicillin. Also if you think you might be pregnant then take a pregnancy test.
My period is suppose to come on the 27th. If it doesn’t then I could be pregnant? I know it’s too soon to test. I have been having bad cramps and lower stomach pain since the first day of bleeding ( really was a few hours and it was very light) I know something is wrong because I never miss a period and it’s always normal. I stopped taking the medicine it was only for my throat.
Hello Shameka, please take a pregnancy test if you think you might be pregnant.
Hi
I took ciprolex-tz for infections, and I have not seen my period. I’m seven days late. Could it be it or I’m pregnant
Hello Nabby, the medication you are taking could be the cause for your missed period, however if it it does not return normally then take a test. All the best.
I started taking metronidazole the day that my period was due, could that amount of time cause it to be late ??
Hi there Andi, seems as though you are late, please take a pregnancy test to confirm that you are not pregnant. All the best.
Hi there, I have been on the birth control pill for over 2 years now. For the past two weeks I have been on APO-ITRACONAZOLE taking 2 pills a day for 2 weeks. I had to switch from generic brand antibiotics to a name brand for the second week. I was supposed to get my period on march 22 and received all the normal signs I usually get before my period (acne, hunger, bloating and some cramps). I was wondering if these antibiotics are messing up my cycle. It is almost 7 days late and I’m a little worried.
Hi there Unknown, yes the taking of anti-biotics have been known to alter a menstrual cycle and delay a period. Give it a couple of days and all the best.
I took ampliclox few months ago and my my menstrual flow won’t stop wt thick blood…. This abnormality has affected me psychologically
Hello Fatimah, sorry to hear about this, please see your general practitioner.
Hi I have been taking Sumapen for 10 months. My period never came last December up to now.
Hello there Hannah, if you have any concerns re the taking of Sumapen see you doctor to prescribed the medication. All the best!