The People's Perspective on Medicine

Niacin Side Effects: Hot Flashes Are Nasty

Slo niacin, cholesterol, HDL,

Q. I am taking niacin 1000 mg to improve my good cholesterol. I get a hot flash about 20 minutes later that lasts about 15 minutes.

Is this normal? My doctor recommended niacin since the bad LDL cholesterol is fine but the good HDL is too low.

A. Niacin (vitamin B3, or nicotinic acid) has been prescribed for more than 50 years. (At the doses required to produce results, niacin must be considered a medicine and its use should be supervised by a physician.) A landmark study published in 1986, the Coronary Drug Project, tracked heart attack victims for 15 years. Men who had been prescribed niacin had substantially fewer repeat heart attacks and 11 percent fewer deaths. The benefit persisted for many years, even after they stopped taking the niacin.

Despite the fact that niacin has been prescribed for decades to improve lipid profiles, researchers still do not understand exactly how it works this magic. Niacin lowers bad LDL cholesterol by anywhere from 15 to 40 percent. Triglycerides also come down significantly. Niacin is one of the few compounds that reduces Lp(a) and raises good HDL cholesterol by 10 to 20 percent.

Best of all, niacin is inexpensive. Compared to today’s powerful prescription drugs, niacin is a steal. A 2-month supply can cost one-tenth as much as the same amount of a statin-type medication. Of course, at the doses that are required to lower cholesterol and reduce the risk of heart disease, medical supervision is essential. Liver function must be monitored periodically to detect any enzyme elevation that might signal damage. Doses that are prescribed range from 300 to 500 milligrams at the low end to up to 3,000 milligrams at the high end. Only a physician can determine the most appropriate dose and supervise safe treatment.

Niacin frequently causes flushing, itching and tingling about 20 minutes after swallowing it. Some doctors suggest taking a low-dose aspirin 30 minutes before niacin to diminish the hot flashes. Food may also slow absorption and reduce the discomfort.

To learn more about natural approaches to cholesterol control and triglyceride management we suggest our book, The People’s Pharmacy Quick & Hand Home Remedies from National Geographic. It discusses the benefits of cinnamon, Certo and grape juice, oatmeal and barley, red yeast rice, vinegar and walnuts. You will also get a recipe for an unusual smoothie containing orange juice, diced banana, frozen berries, raw rolled oats and flaxseed meal. One woman reported that this recipe lowered her son’s total cholesterol as well as his bad LDL cholesterol while raising his HDL cholesterol.

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About the Author
Terry Graedon, PhD, is a medical anthropologist and co-host of The People’s Pharmacy radio show, co-author of The People’s Pharmacy syndicated newspaper columns and numerous books, and co-founder of The People’s Pharmacy website. Terry taught in the Duke University School of Nursing and was an adjunct assistant professor in the Department of Anthropology. She is a Fellow of the Society of Applied Anthropology. Terry is one of the country's leading authorities on the science behind folk remedies. .
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I took Slo Nicin 500mg with a meal. About 2-3 hours later I was burning up, body all red, hot, flush, throbbing. It was terrible and I don’t know what to do about it as my doctor wants me to take 1 tablet a day. It doesn’t happen all the time but seems to build up in my system and then let go all at once? Occasionally I forget to take it every day so this maybe a problem? I am thinking of breaking the tablet in half and then take it twice a day?

I noticed a direct correlation between eating sugary foods and getting flushes from my Niaspan. I got more frequent flushes from niacin, so Niaspan seems to have helped with that as long as I’m not eating something sweet. Niacin has also been shown to cure schizophrenia, and hey, since they are out to get me, I might as well know it’s them and not some brain malfunction, LOL!

I am taking Niacin also for cholesterol reasons. I get a hot flash about 10 to 15 minutes after I take the pill, but it does not happen everyday. Is the niacin still working good in my system if I do not have a hot flash everyday after taking the pill?

They are flushes, not hot flashes. Taking the niacin on a full stomach and with plenty of water prevents them for me. Helps a lot if either your doctor or pharmacist warn you about the flashes and how to prevent them and start you on them gradually, building up to your full dose over a week or two. Mine didn’t and I freaked when the first flush hit me. Had no idea what was going on, even my brain burned like it was on fire! Couldn’t reach my dr or pharmacist as they were both at lunch, so I went on line and researched it. That’s where I learned that taking a Benadryl a little while before the niacin helps prevent the flushes. After you’ve been on it a while, your body should adjust and you should have less reaction.

For what it is worth: the flushing effect from Niacin usually diminishes as your body becomes accustomed to taking it, then becomes a very minor and occasional mild sensation. At least that was my experience, and from what I understand — most others (from my doc).

My insurance plan pharmacy raised the price of Niaspan and substituted me with Niacin ER. I take this 1000mg tablet after dinner along with an aspirin. I now wake up at around 4AM feeling and looking like a frigging shrimp in the frying pan. This Niacin ER stuff is awful.
I’m surfing the internet trying to find something to help reduce the flushing while drinking a tall glass of ice water. No way am I taking this again. !

I take 1500 mg a day of slow release Niacin in 500 mg tablets 3 times a day. I would never take 1000 mg of Niacin in a single dose. I am able to prevent flushing by eating 2 slices of whole grain bread and a third of a banana just prior to taking the 500 mg Niacin tablet with water. I also started adding a few whole grain blue corn chips. This kind of food prevents the Niacin from rushing into you bloodstream all at once and causing a flush. If I slip up on the no flush regimen, I am lucky, since the only place I flush is on the underside of my arms, not all over like you. By the way, the reason I take Niacin is that Statins give me some memory loss. Good luck!

Hot flushes it just a symptom of elimination, so this is not to be worried about. I had these quite often, after taking niacin, and now much less. The fact that I have been mostly on organic food these last few years may also be an explanation.
I hope this helps.

I had all kinds of MEMORY LOSS problems with Simvastatin and stopped taking even though my Cardiologist told me I was going to die.
I started taking NIACIN –the regular kind– two pharmacist tole me the SLO-RELEASE & NO-FLUSH Niacin do not work like the straight Niacin

Why didn’t you recommend FLUSH-FREE NIACIN? It is manufactured by Finest, and I purchase it at Walgreens. My doctor recommended it — I was not aware it existed and stopped taking the ‘regular’ Niacin because of the flushing. My cholesterol went down about 52 pts in 3 months!

I’ve been taking crystalline niacin (e.g. immediate release) for over 8 years and I wouldn’t switch to a statin. I’m fair skinned and when I started taking it, I would turn beet red and experience very intense itching. Taking aspirin in the beginning helped a little bit. I’ve tried taking it two times a day and three times a day, and twice daily works best for me. Every time I switched to three times a day dosing, I developed elevated liver enzymes. Never had that problem with twice daily dosing. I’ve been on 2 g twice daily for at least 7 years. The extended-release form of niacin has a much higher incidence of adverse liver reactions.
The flushing caused by niacin is a result of two different pathways. The primary pathway is by a niacin-induced release of prostaglandin D2 which occurs primarily in skin cells. Aspirin helps to reduce the effects of the prostaglandin. The other mechanism is via serotonin release in platelets. The only way to block this is using drugs such as Periactin or Thorazine, both of which turn you into a zombie.
I take two different formulations. Right before my morning workout, I take niacin capsules (Twinlab). For some reason, the flushing is much less noticeable when the flush occurs during strenuous exercise. Right before bedtime, I take a delayed-release (not time- or extended- release) tablet that takes an hour to dissolve before the niacin hits my system all at once. By that time, I’m asleep.
It’s also important to take niacin continuously. Missing several doses in a row resets the tolerance to flushing to a much lower level.
After my older brother’s second major heart attack, I went to a cardiologist for an evaluation and an EBCT and it turned out that I had mild calcification in two of my coronary arteries. The doctor added simvastatin to my niacin and during that period, my total cholesterol dropped to 97, which is dangerously low. After developing elevated liver enzymes, I had to stop both niacin and simvastatin for a month to give my liver a break. I had an NMR lipoprotein test performed during this time, and although my HDL was 52 and triglycerides 50, the test showed that I had predominantly small, dense LDL particles. I then restarted niacin and saw my cardiologist 4 months later. He was adamant about putting me back on simvastatin since my LDL was elevated… 80!
I fired him.
Two years later, I had a second EBCT to check for coronary artery calcification. My calcium score had decreased, something that would never happen if I had been taking only a statin.
Niacin had been in use for over 50 years and the side effect profile is well established. Not so with statins.

My husband and I worked up, slowly, to 1500mg of Flush Free Niacin. We take an 81mg aspirin one hour before taking the Niacin and then after taking the Niacin we go to bed. All has gone well and we are free of ill effects. I was not able to take his brand of Niacin (I still flushed), so I found one that I could tolerate. We have our kidneys and liver checked 2 times a year. Our HDL & LDL numbers are in the normal range now. All of this is under the supervision of our physician.

My Doctor has me on prescription Niaspan. She has me taking a baby aspirin (81mg) about 30 minutes before the niaspan. It has to be as close to 30 minutes as possible. If I take it too soon or too late after sometimes I get the flashes. It almost eliminated the flashes. I only get them 1 time a month or less, sometimes it`s a couple of months before I get one, I can take that, at least it`s not everyday.

My HDL is 100, about the same as my triglycerides. I have heard Mary Vernon say that the ratio of Triglycerides to HDL is the most important indicator of health. I keep the tri down by not eating many carbs, especially flour or sugar, and limit fruit. I am convinced that my HDL is from eating coconut fat and cooking with it, and using all the butter I want. I suggest you listen to The Oiling of America by Sally Fallon. God made us with cholesterol, and only the drug companies benefit by making our livers stop producing it. I think drugs make more people sick than well.

Vitamin C is also effective for reducing the flushing and itching from niacin. I recommend the crystalline or powdered form so you can take a very small dose – like 1/8 tsp. in a 4 of water to start and go up from there. Vit. C can be diuretic for some people.

I have found that half an regular aspirin about 20 minutes before taking 1500 mg Niaspan generally alleviates my flushing. Consuming alcohol even one beer or glass of wine will magnify the flushing for me.

I’d like to hear more about hot flashes and what they are and what causes them. I am wondering how they relate to thyroid.

Why didn’t you mention “niacinamide” which supposedly delivers the niacin without the flushing?

I take 1,000 mg of FLUSH FREE NIACIN or NO FLUSH NIACIN & my doctor was **ADAMANT* about NO FLUSH or FLUSH FREE Niacin.
I have no problems with this, but a good brand from a health food store would be best.
I can’t believe any doctor would prescribe pure NIACIN! And I can’t believe PP didn’t suggest this.

I have been taking high-dose niacin (regular, not slow-release or niacinamide) for about 30 years because of low HDL-C and high Lp(a). Although people have different tolerance levels to niacin, as judged from many friends and family members, most do okay if the dose is raised slowly, beginning at 50 mg twice a day and increasing at intervals of a week or two and always taking the niacin after meals. If flushing is a problem at a given dose, it is then easy to either maintain the dose for a longer period or drop back slightly until symptoms are gone. I have never taken aspirin (or other NSAIDS) before my niacin and have taken a gram (1000 mg) 2 or 3 times a day with only occasional mild flushing–perhaps once or twice a month.
Although niacin is inexpensive, high doses if bought from retail channels can cost quite a bit, and most insurance policies consider it a supplement rather than a drug and will not pay for it–even if ordered via prescription. Some discount online companies like VitaCost carry high-quality niacin preparations at reasonable cost.

When my Dr. (an internist) and I decided to try to get my HDL up from about 35 (total cholesterol was 135), she asked me to try 10 mg Lipitor instead of the 40 mg Zocor (generic) I had been taking for years. I quickly developed leg pains so we agreed to try only niacin – first 500 then, if no flash problems, up to 1000 mg.
I used a OTC Niacin product from Target which says it doesn’t cause flash, and it didn’t for me. After 6 weeks, my HDL was up to 50 but my total was way up to 245, so we agreed I needed the statins. I suggested trying only 20 mg of the Zocor generic with the 1000 mg niacin and she agreed. After 6 weeks, my total was 159 and my HDL was 42. We are both happy with this compromise (although I wish I could have kept my HDL of 50).

Often, after a period of time, the Niacin flushing will diminish or stop. I have taken it for some period of years now, and in the beginning, often “flushed” but at this point rarely does it happen.

I had not only flushing from the prescription form of Niacin, but it caused my liver function test to spike quite dangerously. This stuff isn’t to be taken lightly!

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