niacin and spotting in between periods

I’m 26. I started taking Niacin (250 mg per day) about 8 days ago. Today I started spotting (coincidentally it’s also my ovulation day). However, it is not typical for me to spot in between periods. My period is due 2 weeks away. It must be Niacin. Damn. But if it helps me acne improve, I guess I won’t complain.

This happened to me yesterday. I have a history of severe menstrual cramping, which I can prevent by taking a heavy dose of NSAIDs (like Ibuprofen) just prior to and during the first couple of days of my period. Yesterday, however, I was not even close to being due for my period. I had just finished it a week prior, actually. I took Niacin for the first time ever, 500mg, and had the expected flushing symptoms. Just as the flush was starting to calm down a bit, though, I started having extreme abdominal pain that felt like menstrual pain. It was really bad, though. I felt like I was having a baby (I had an unmedicated birth, so I know what I’m taking about here). I was in so much pain that I couldn’t speak and could only moan, and I ended up calling 911 and going to the ER! It took three doses of heavy duty narcotics to even touch the pain. Later, when I went to the bathroom, I saw that I had had some vaginal bleeding. While I was recovering, I did a bit of reading on Niacin. It turns out that Niacin causes a massive release of prostaglandins into your bloodstream. Prostaglandins are the same chemical messengers that cause menstrual cramping and uterine contractions during labor.

It’s crazy to me that you can’t find any info. on this potential side effect of Niacin online! Even the doctor in the ER had never heard of it, but, when I told him about the prostaglandins and my bleeding, he agreed with me that it was uterine contractions caused by the Niacin!

This is just another example of how much BS it is that almost all medical studies have been done on men and not women. I have a feeling no one has ever even checked to see if Niacin might effect women differently than men.

I’m curious how long your bleeding lasted. I’m 36 and haven’t had spotting in years. Last Tuesday I accidentally took 500 mg of niacin instead of 250 and started bleeding that same day even though my cycle was just two weeks prior. It is now a week and a day later and I’m still having a full blown period that won’t stop. I’m worried I messed something up.

Im 54 and havent had a period in almost 2 years. Started taking niacin 3 weeks ago and started cramping and spotting a couple days ago. I stopped taking it and am wonderung how long this will last.

Thank you ladies for your comments because now I know it is the Niacin that has caused me to start my period about a week and a half early. I have only taken one dose of it. Wonder if I keep taking it, will it level out my menstrual cycle back to normal or will I have spotting every day?

Im not sure. I quit taking it,but I had spotting off and on for about 2 weeks. Still have muscle cramps after almost 4 weeks.

Well thank you all for your stories. I haven’t had a period in almost a year and started tonight. I started using a small dose of niacin a few weeks because read some good reports on taking supplements of it, and I agree 100%, why isn’t there something medically researched about this? It’s very obvious we aren’t doctors or specialists and we have figured it out. Thanks again for sharing your stories

This is happening to me right now. Took niacin for the first time ever on Thursday. Friday had a small amount of bleeding - Saturday there was slightly more but then I woke up in the night with a large amount of blood. 2 weeks after my first period.

I started taking Niacin 500 mg twice a day for Raynaud's syndrome and I started spotting in between periods. I did not think much of it because I'm in perimenopause and figured it might be hormonal. But then I started having a serious heavy period that seemed unending. I stopped taking niacin and it's slowed down the hemorrhage. There is defiantly a correlation between menstruation and the consumption of Niacin! This should be on a warning label because I really thought I would have to go to the ER since I was loosing so much blood.

Thanks for this because I was so scared I started cramping and then had bloody like discharge but my period was 2weeks ago and I just took a niacin about 3 hrs ago

My wife started taking niacin and she told me her cycle was 10 days earlier, she is taking 1000mg a day