The dreaded niacin "flush"

As most anybody who takes niacin knows, it can cause a hot flushed feeling over the chest and face that is generally harmless, though quite annoying.

Many doctors are frightened by this response and will warn patients off from niacin. Some people who take niacin are so annoyed that they find it intolerable.

However, a very simple maneuver can relieve the hot flush in over 90% of instances: Drink water. Let me explain.

I usually instruct patients to take niacin at dinnertime. That way, food slows absorption modestly. I also ask them to drink water with dinner. If the flush occurs after dinner (usually 30-60 minutes later), then drinking two 8-12 oz glasses of water immediately breaks the flush within 3 minutes in the great majority of people. It's quite dramatic.

Doing this around dinner (lunch works just as well) allows sufficient time to clear the excess water from your body before bedtime and spare you the aggravation of disrupted sleep to urinate. Drinking plenty of water works most of the time. Only an occasional person will need to take a 325 mg uncoated aspirin to more fully break the flush. I generally suggest that patients keep the uncoated aspirin in reserve if the water doesn't provide relief within a few minutes.

Thankfully, the intensity of the niacin flush lessens, often disappears, with chronic use.

Why do some people develop the flush and other don't? It is believed that some people metabolize niacin more rapidly to a compound called nicotinuric acid, a niacin metabolite that causes dilation (relaxation) of skin capillaries--thus the flush. The rapidity of converting niacin to nicotinuric acid is determined genetically.

An occasional person really struggles with niacin to the point of intolerance. However, on the positive side, these people may also be "hyper-responders" to niacin, i.e., they show exagerated benefits in raising HDL, reducing small LDL, etc., from small doses such as 250 mg per day.

If you experience the hot flush of niacin, think water to put out the fire.

Comments (55) -

  • Anne

    5/18/2007 3:17:00 AM |

    I had a severe reaction to my first dose of niacin - wish I could remember what dose was prescribed. I not only had a flush, but I itched all over and my face and mouth swelled up. Was that an allergy or can the niacin flush get that bad.

  • Dr. Davis

    5/18/2007 11:29:00 AM |

    Your reaction is a rare variety that I've seen only a handful of times. There's no such thing as allergy to niacin itself, though someone rarely can be allergic to another component in the capsule. It is possible to take niacin after such a reaction, but you need to work with your doctor. I've re-introduced niacin after such reactions at very small doses of, say, 50 mg (immediate-release) and built up very slowly over months, even years. This has worked out well.

  • Anne

    5/19/2007 10:08:00 PM |

    Thank you for your answer. The niacin I was prescribed was Niaspan. I can ask my cardiologist if there is a gentler brand and a lower dose.

  • Kathy and Wes

    7/26/2007 10:42:00 PM |

    My reaction to 500mg of niaspan was burning from head to foot 2 1/2 hours after taking it. In addition, my heart was beating so fast I couldn't believe it.  If felt like I was being burned with a curling iron all over my body.  The only thing I could do to relieve it was to splash cold water all over me.  My Dr. wants me to try it again. taking a baby aspirin an hour before hand.   I only had this twice out of four times.  But I am very afraid to try it.  It lasts almost an hour.

  • Kathy and Wes

    7/26/2007 10:48:00 PM |

    My Dr. put me on 500mg of Niaspan. I have taken it 4 times and twice had the worst reaction.  I became beat red from head to toe, and my skin felt like I was being burned with a curling iron.  The only relief I could get was to splash water on my skin.  This lasted almost an hour.  My heart was also pounding at an excelerated pace.  My physician would like me to try it one more time with a baby aspirin, which I did once.  Are you sure that it is safe with a reaction like that?



  • Dr. Davis

    7/27/2007 12:05:00 AM |

    Plenty of water--meaning 16-24 oz, if okay with your doctor--with your niacin can be very helpful in the beginning. In my experience, people who live with chronic dehydration (there's lots) struggle the most with niacin.

  • Dr. Davis

    7/27/2007 12:07:00 AM |


    I can NEVER offer medical advice online.

    I can only tell you that I've had many people navigate through these feelings just by paying attention to hydration. Only an occasional person is truly unable to tolerate it.

    Another option I use in my patients is to induce "tolerance" by accepting a small dose, e.g., 250 mg SloNiacin (Upsher Smith) for several months, and increase it very slowly. But you need to discuss this with your doctor.

  • Doris

    7/28/2008 3:50:00 PM |

    I have taken Niacin for over two years. By brother-in-law was in the emergency room with flushing. The doctor had given him Niacin and told him to take a big dose daily. I can't remember if it was 2000mg for sure, but I think it was. I began at 100 mg and on the fifth day went to 200 mg. After taking that for 4 days I upped it to 300 mg. You get the pattern. I eventually made it up to 3000 mg. I buy it at the health food store in the mall because the Niacin in the discount stores tend to be nonflushing. I still flush occasionally, but not severely. I enjoy the flush as I know, or pretend,that is where the little niacin crumbles are eating up the cholesterol. Ha. Good luck. I found this suggestion online posted by a doctor.
    btw, I have itched a bunch for maybe 10 minutes while it flushed. My flushes are not too severe to continue. I did go off Niacin and am restarting because I looked online for Niacin overdoses and I had some of the symptoms. I decided I had got too high on dosing.

  • Jenn

    8/22/2008 1:31:00 PM |

    Why is Niaspan considered a better medication (at least by my doctor) than over the counter niacin, when it causes so much more flushing? On regular Niaspan, I don't flush every day, but if I do, it's anywhere from 2-18 hours after I take it. My doctor started me on the Niaspan-Crestor combination, and I can set my watch by it- 8 hours after I take it, every day.
    It's hard to get ready for work, when my face is blotchy and puffy and it hurts to apply makeup or comb my hair. Is flushing connected to diet and exercise? That is, is it supposed to make you flush if you eat the wrong things or don't exercise? I can't understand why my doctor would insist on my using Niaspan unless he's trying to use the flushing as a behavior modification program.

  • Anonymous

    9/1/2008 9:22:00 PM |

    I had an odd reaction to Niacin.  After eight wonderful days of taking it, I woke up one evening with a feeling that my body was on fire from head to toe.  Remembering that I needed to take an aspirin when flushing had occurred, I went to the kitchen where I had a series of seizures.  Upon eliminating everything in me, we called an ambulance.  
    The ER physician said it was a normal reaction and to continue to take the medication as prescribed.  I called my family doctor the next morning and he said I did have a reaction, which I stopped at that moment.  
    So, did I have an allergic reaction to the medication or just a seizure out of no where?


  • Murf from WA

    10/13/2008 8:20:00 PM |

    this doc is cool but u guys are all a bunch of little whiners! Niacin flush is such a rush I can literally feel all the toxins leaving my body and it feels GREAT. so quit complaining. this "flush" is doing you good. I assure you. The whole point is to flush. calling the ER because you are flushing may be a sign that you are a hypochondriac. maybe u should see a therapist?

  • Anonymous

    10/18/2008 2:56:00 PM |

    I agree w/"murph" but not so aggressively--the flush is good, good, good.  You are just freaking out a little but because it's odd and unusual to you, at first.  You should be flushing, it's increased blood flow that is getting all the nasty stuff out of your system and after the pinkness subsides I have been asked about what I'm doing with my skin because it's glowing!  I swear my skin looks clearer and more youthful.  I take it when I wake up, before breakfast & a shower and by the time I get to work my pink is gone, I'm more awake & my skin is glowing.  LOVE IT, DON'T FEAR IT.

  • PinkyTink

    10/30/2008 4:37:00 PM |

    I used to work in a pharmaceutical - packaging niacin. I would have my hands gloved, my arms covered, my hair in a net and wearing scrubs with a lab coat over them - just inhaling the niacin while working with it in raw form left me very sensitized to niacin reactions, which I attribute more to a feeling of a bad sunburn for about an hour. I too have had difficulty breathing and swelling of my esophagus during a reaction after higher doses or inhalation during the time I worked in the lab.
    I do not feel those who are speaking here are hypochondriacs and unless you've gone through something, you should really not judge others their symptoms - clearly the seizure person would argue you that their issue was not in her mind, do you not agree?
    I personally just find the reaction plain annoying, but have had to adhere to my doctor's warning of being wary of certain forms and doses of niacin due to my persistent reaction post-contact... those who do not understand this, i have no worries; nor am I whining or complaining - facts are facts - they are what they are - I make no apologies for stating them. Enjoy your day Smile

  • New to Niacin

    11/6/2008 2:45:00 AM |

    I agree with PinkyTink that the feeling most like a niacin flush is like a sunburn. Here's my account for those interested in case studies. I tried niacin (250mg) for the first time two days ago and thought "well, this feels nice; it's kind of hot and tingly as if I were blushing over my entire body." If some is good, more is better, right? Wrong! Yesterday I tried 500mg, encouraged by the fact that the recommended dose is 1-2 grams, and determined to fix my cholesterol problem all in 1 day. Nope. I spent about 3 hours with what felt like the worst sunburn that I've ever had (and being a native to SoCal, I've had a few). The burn started on my face, which was fine since it doesn't touch anything. It then included my face, shoulders and upper torso, which was moderately annoying but I was able to continue working. At the 1 hour mark or so, the fire had engulfed my lower torso and my buttocks as well so I kneeled in front of my computer (the prickling and burning too intense to put pressure on) to work. About a half an hour after that, my entire body was on fire and I just gave up and paced around until the intensity was bearable at about the 2.5 hour mark. It was incredibly itchy from the 1.5-2.5 hour mark, and I did rub and put an ice pack on excessively itchy spots occasionally, which relieved a bit of the discomfort. (I didn't know about the dehydration fix, so I'll try that next time.) I am planning on continuing with niacin, but with a slower increase to get my tolerance up, YMMV. To those who don't think the flush is a big deal or pretty debilitating, we may be describing different levels of intensity.

  • headlightsonthehighway

    11/28/2008 6:28:00 AM |

    I've taken half of a 100mg dose and it usually causes just a bit of flushing for around 15 minutes. But tonight I decided to take the whole 100mg and my face not only felt like it was on fire, it went to my hands, then arms, neck, shoulders, then my legs. My face (mostly my nose and upper lip) swelled up and I looked like I had fallen asleep at the beach for 8 hours. My heart raced and I was afraid that maybe I was having an allergic reaction, but after about an hour, it subsided. I will only take the smaller doses from now on. The flushing isn't so bad, but the swelling scared me a little.

  • Anonymous

    3/17/2009 12:03:00 PM |

    I had an intense, long-lasting niacin flush similar to the worst mentioned on here. I also have some menopausal flushing (even with estrogen), rosacea, and migraines. People with any of those conditions should be careful about niacin. I don't think it is all that rare to have a very bad reaction to it, because there are a lot of people who have one or more of these conditions.

  • Kaylin

    5/1/2009 4:25:00 AM |

    I took 500mg of niacin today and had quite a flush!  It was a very good thing that I happened to be at my parents' house with my three young children instead of driving, because after my skin felt sunburn-hot and turned beet-red all over, everything started looking very bright and I would have passed out if my mom hadn't led me to a bed to lay down.  I am so thankful she was there because she had to take care of my kids while I laid on the bed for a couple of hours recovering.  Almost passing out is not a hypochondriac invention, people!  I thank the good doctor for his information as I am encouraged to continue taking niacin, but at much smaller doses until my body gets used to it.

  • Michele

    5/18/2009 3:03:00 PM |

    Hi. I was doing fine on 500 mg of time-released niacin twice a day for five months with only minor flushes. Yesterday, about four hours after taking the first 500 mg pill, my face flushed beet red and got very hot. Ditto for my upper back. Can this be due to the niacin, even though I didn't just start taking it and the flush occurred hours after I took one?

  • Anonymous

    5/29/2009 11:09:11 PM |

    I just bought a new multivitamin at a health store and didn't notice it's huge level of niacin and I had a severe reaction like some of you described...full body sunburn, itching, rash, burning, and swelling of upper lip. My heart raced. I had to run home from work and take a Clonidine that I had for rosacea flushes and a benedryl (probably a bad idea, but I was desperate for relief) and am still waiting for some relief. I would beware of the flushes...those of us with rosacea know, with every flush comes inflammation and capillary damage which can age you and ruin your complexion.

  • Cookie

    6/12/2009 2:43:40 AM |

    Be careful advising people that there is no such thing as a niacin allergy. I cannot even tolerate 2 bites of food that has been supplemented with it, without my lips swelling and burning and itching starting. I first discovered my allergy to it by taking it as a supplement by itself. I broke out in hives and itched terribly for a few days. I didn't want to believe it, so I took it again a month later. Repeat, only worse this time. I can't even take it in any form, energy drinks, cereal bars or B100. I drink 2 quarts of water daily, and as much as I can more,
    when I realize I have eaten it in something by accident. This is the most serious itching and welts I have ever experienced. Hoping this helps someone else, Laura

  • Dr. William Davis

    6/12/2009 7:37:47 PM |


    You do NOT have a niacin allergy. If you did, you would not be alive. Niacin is required for human life.

    What you have is an unusual idiosyncratic reaction. This does not mean that niacin is safe. It means that you are among the rare exceptions in tolerance to greater than pellagra-preventing doses of this B vitamin.

  • Cookie

    6/20/2009 3:57:39 PM |

    Hi Dr Davis,
    I do believe you may be right that the allergy is not just Niacin alone. I have found I have severe reactions to Niacinamide, but not Niacin alone. I looked up the difference on Wikipedia and they are very close in their chemical makeup and definition. But, they are not the same.
    The bond is N,O,NH2

    Whereas, the bond for Niacin is N,O,OH.
    I am no scientist, but my body certainly knows the difference.
    I hope this helps someone else.

  • Anonymous

    7/26/2009 3:54:52 AM |

    A doctor told me to take a baby asprin and 500 mg of niacin for one week then increase it to 1000 mg.  Presently, I am on my third day of 500 mg, here is my experience with flushing.  The first day was no problem.  I took one baby asprin before my meal and the 500 mg of niacin after my meal. I felt like I had a bad sunburn, but everything was fine. I noticed I didn't turn red where I was sitting, but everywhere my skin was exposed was red and hot.  Day 2 - I took 2 baby asprins before my meal and 500 mg of niacin after my meal. The flushing was almost unbearable.  Quite different from day 1.  I stripped my clothes off because I couldn't stand anything on my skin, stood in front of a fan, and iced my body.  Then I remembered about yesterday the parts of my body that were covered did not have a bad sensation, so I put clothes back on and jumped in bed with covers.  That did help relieve the symptoms.  Today is day 3.  I was scared because I didn't want a repeat of yesterday.  I thought about reducing my dose, but I had a plan.  I took 2 baby asprins before my meal and 2 motrin and 500 mg of niacin after my meal. I put on long pants and a long sleeve turtleneck sweater, and had an ice pack ready for my face and hands. The flushing episode went really well. I didn't even have a bad sunburn feeling.  It was just slight.  I don't know if this will work for anyone else or on day 4.

  • Anonymous

    7/27/2009 1:54:58 AM |

    Day 4 - I did the same thing as day 3.  I took 2 baby asprins before my meal and 2 motrin and 500 mg of niacin after my meal. I put on long pants and a long sleeve turtleneck sweater.  I had very slight hotness in my hands and face.  That is it.  I didn't need an ice pack today. I don't know why this method works, but if it will help anyone else I'm glad I posted my comments.

  • Laxana's World

    8/7/2009 3:28:40 AM |

    I had never been told about any reaction to Niacin...I took it before dinner and thought I was on fire...I found this site and drank water and took helped, but a cool water bath w/ baking soda and time finally made it better (it's been three hours and my skin is still extremely sensitive and somewhat flushed)...this has been one of the more unpleasant side effects to any medication.  I want to continue to lower my cholesterol, and already take red rice yeast and fish oil...I don't know if I can continue the fun.

  • Phil5115

    8/22/2009 9:55:04 AM |

    I get the itching and burning as well, but the worst is a swelling sensation in my ears.  Not pleasant, but my triglycerides are improving.

  • Anonymous

    8/31/2009 6:56:12 PM |

    Being flushed is nothing.  I took an over the counter niacin tablet and besides turning as red as a lobster (no exaggeration--I was the color of a stop sign) my blood pressure fell fast and I landed on the floor unconscious.  There are those of us with a severe reaction to niacin supplements; it is not trivial and it is well worth thinking about.  Having such a precipitous drop in pressure is dangerous.

  • robert

    9/2/2009 11:08:39 PM |

    Hmmm...I take niacin like this - 0500- 500mg SloNiacin; 0900- 500 mg Miacin; 1200- 500 mg Niacin; 1600- 500mg Niacin: I rarely flush and when I do, it is extremely mild and does not even register. I don't know what all the fuss is about. Maybe I am taking it incorrectly?

  • Kris

    10/17/2009 12:59:22 AM |

    The only time I get a flush is when I have eaten garlic and then taken the niacin.  It is not pleasant and scared me very badly the first time.  I do not know why this happens.  Has anyone else had a similar experience?

  • Anonymous

    10/26/2009 7:26:52 PM |

    My experience was extreme. I have been taking the Niacin with Crestor for 3 days. When I sat down to lunch today I suddenly felt warm and took off my sweater. within 2 minutes I was burning in agony from head to foot and my body was shaking. I was itching, shaking and burning while my heart was racing. I was beyond beat red and it was far more painful than any sunburn I had ever experienced. I was in tears and scared witless. I am a 40 year old ex football player. I am not afraid of a little pain, this was torture! I felt like someone was burning every inch of skin from my body all at once and I could do nothing but lie down and scream. My Wife called the doctor who said it was normal and would pass. My triglycerides were about 108 but my doctor wants to see them at 80. For those who think it's just whining, I hope you never have to experience what I have just gone through! I wouldn't put that on anyone no matter how cluless they were. Until you've experienced a severe reaction, do not even try to minimize the pain. It is beyond belief. That was 4 hours ago and I am still itching.

  • Doug

    11/17/2009 7:24:50 PM |

    I have used Efudex and fluoruracil for treatment of Actinic Keratosis with the last treatment 2 years ago.  Since then, my arms barely show any signs of damage, but my legs still showed the damage which would be more prevalent when I got hot and sweaty.  I took my first 500 mg dose of Niacin 4 days ago at night.  I only felt a little flushing and tingling, and didn't think it was bad at all.  The next day, my legs looked as bad as they did after using the fluoruracil for 4 weeks.  I have not taken another dose of Niacin and my skin has not improved at all.  I think the Niacin is telling me that the Actinic Keratosis was not destroyed on my legs.  Do dermatoligists use Niacin to make AK's more pronounced so that they can find them?  Will my current condition get better?

  • John

    12/20/2009 2:18:28 AM |

    Hello, all! I have been taking Niacin daily for more than 30 years. I don't take it for cholesterol but rather as a treatment for Meniere's Disease but that's another story entirely. I believe because of the length of time that I've been a Niacin user that I have more experience with it than perhaps anyone, anywhere. I can go months without a flush and then I can experience a mild flush eveery day for a week. I flush much more with non-timed release forms than with timed release forms. Some times I experience a really bad flush. I mean REALLY bad. Not just the feeling that's akin to the worst sunburn that I've ever experienced but the feeling that the skin on my face weighs many pounds more than it possibly could and if it gets REALLY bad, my stomach tightens up as though it wants to screw itself into a tiny, tiny ball, nearly doubling me over. Twicee in my life I have come perilously close to passing out during a flush. Once while driving and the second just about an hour ago tonight. Tonight's was the worst that I have ever experinced by far. It got so bad that I actually feared that I was on the verge of dying. This flush lasted far longer than any before it. Usually they pass in 15-20 minutes for me but tonight's effects have drawn out for more than an hour. As I type this post, my hands are still shaking as I am "coming down" from the flush. The thing of it is though that I knew it was going to be bad tonight, just not this bad. You see, I usually take my Niacin in the form of a timed-release caplet (Slo Niacin) early in the morning and if I forget to take it early in the day, the likelihood of a bad flush increases the later that I take it. Yesterday I realized at 3PM that I hadn't taken my Niacin so, fearing the severee flush, I simply didn't take it at all. Today, I once again forgot to take it early and risked taking it at 4PM. The flush didn't hit me until 7 but when it did, it grew slowly and to a height I had never experienced. WOW!I'm just about back to normal after an hour and a quarter!!! I just read the advice about taking an aspirin and I will keep some on hand in case it gets this bad again. I also think I'll make a SERIOUS effort to remember to take it first thing in the morning from now on!

  • Bram

    1/26/2010 1:50:43 AM |


    I really had to post a comment too.
    After reading John's post I felt a lot better. I also had the worst flush ever today. Normally i take 1000 Mg Niacin twice a week, but last week I skipped my doses, just to give my body a little time for itself. Normally the flush starts after 1-1.5 hours and than slowly my body starts to feel a little bit hot from top down, not too bad, kind of nice even. Today after 20 minutes or so, in one second my head became SUPERHOT, my lips and my facial muscles felled paralized, my heart started racing (maybe because of the new strange experience) I looked in the mirror and my complete face was hanging down. I've never seen this before so my heart started beating faster and I started hyperventilating. At that moment I really thought it was the end of my life. It was really bad. But now I know I'm not alone so we'll see what happens next time;
    Maybe a smaller dose, this was really scary.

  • Anonymous

    1/30/2010 9:07:17 PM |

    I started taking niacin yesterday (250 pil per day), no flush, but today I experienced it.  Ears got hot, then face then upper body.  Slight itching.  it lasted about 30 minutes.  Nice.
    I wonder if it is ok to have a glass of wine while taking niacin pills?

  • Anonymous

    2/17/2010 3:48:50 AM |

    Anonymous don't drink wine.  I had the swelling of the lips, face, I looked like my face was about to explode, it was tightened and my face looked like a 20 year olds skin, I itched for 2 hours scratching my arms raw.  I laugh about it now when I read your post, but I was scared.

  • Barbara

    3/28/2010 10:05:40 AM |

    So my cardiolgist told me to take 1 325 mg aspirin 30 minues before bed & 2 Niaspan at bed time.  twice now I have been up for 3-5 hours with the flushing reaction from hell. The thing is I get hives when I get hot. The itching from the flush coupled with the itching from the hives caused by the heat is unbearable. I burn from  head to toe & even went outside to cool off, in just a tank top, in Colorado, with a foot of snow on  the ground. Still burning. The water does seem to be helping. From now on I'll eat at bedtime & dring 24 oz of water to help. I have to work 7 hours today with no sleep.  This stinks.

  • Anonymous

    7/4/2010 10:40:02 PM |

    Hey, I have no problem with the niacin flush (actually feels good -- and I feel great afterwards). However, I stupidly tried the non-flush niacin (because the pharmacist recommended it) which also contained inositol... I had an allergic reaction for the first time in my life (lasted six hours). Had to go to the hospital. Never touching no-flush or inositol supplements again. Real niacin only (you have to ask for it over the counter here).

  • Anonymous

    7/4/2010 10:47:47 PM |

    To continue previous post: I would avoid Niaspan or extended-release niacin or inositol if you have the allergic reactions as posted above (unbearable hives, itching and heat). Real niacin effects lasts about a half an hour and feel good -- and if you don't like that feeling just use an aspirin half an hour before taking it. The actual allergic reaction I experienced with inositol or "no-flush" niacin (as others above obviously have) is hell. Besides, scientifically, only real niacin works for cholesterol or depression (no-flush and time-release are an upselling marketing scam). There is a HUGE difference between the allergic reaction (to inositol, no-flush, and time release) and the normal real niacin flush.

  • Anonymous

    7/4/2010 10:56:53 PM |

    Addendum to previous two posts: the allergic reaction I had started a few hours after I too the no-flush/inositol. The redness and hives covered my entire upper torso, the unbearable itching appearing in random places. The hives and itching became so bad I jumped in a cool shower for over 2.5 HOURS because I was worried that just scratching myself would leave scars. I finally went to the hospital and was given benadryl. Took another hour to go away. Avoid no-flush or inositol or time-release if you have the allergic reactions.

  • Anonymous

    7/20/2010 9:32:53 PM |

    I was taking a rather small dose, a 100mg mega B vitamin. I got the flushing red response, but then my breathing got rather weak and I had to lie down. I tried another pill a week later and exactly the same thing happened. I got really light headed and was forced to lie down.

    Allergy? I see you guys trying 1000mg... how can I react so strongly to 100?

  • Newton Kinglsley IV

    9/29/2010 3:39:50 PM |

    You're probably right about that water. I took 200 mg today with breakfast, a dose that usually doesn't cause me grief. But damn was I baked today. Felt like I was being burned alive and my skin filleted off with razor sharp steel wool dipped in acid.

    But I drank 16 oz of water and that sure seemed to help. Usually I drink a few glasses of water but today I didn't and I bet that's what did it.

    I also took some asa but there's no way that was absorbed quite so quickly. The worst of the flushing stopped in 5 minutes. It's still present, but tolerable.

  • Venkat

    10/1/2010 10:21:57 PM |

    I had been asked to have 500mg Niacin with 350mg asprin first once a day for 2 weeks then twice a day. I never felt much other than a stuffy nose which I didn't know was related but then one night I woke up feeling hot and uncomfortable. Drank water and had an asprin and slept. I stopped taking it after that. My doctor recommended I continue so I started today by having the slow release Niacin in the morning around 10am after breakfast. At 2:30pm while I was driving suddenly I felt hot in the face, hands, body and legs. I realized I was having the flush but didn't know how to control it hence I looked up online and I am glad I stumbled on to this blog. Can't believe that it is just a vitamin causing all this. Side effects seem to be worse than most drugs.

  • Anonymous

    10/22/2010 12:18:26 PM |

    Thanks folks...I have been taking Niaspam for a while now...6 months...working up to 1500 mg a day (taken at night with aspirin). What's funny is in general I tolerate it okay, with only minor flushing, but today I had an ATTACK like many of you describe that was so debilitating I felt like jumping out the window to get our of my own skin. Even getting the water into my system wasn't so easy because I was so uncomfortable. Between the water and aspirin, I'm back to the managable "light sunburn" itch level. I think 1500 mg may just be too large a dose for me and I may need to cut back to 1000 mg. Also, I do occassionally drink, and since I know the reaction between alcohol and niacin is bad, I don't take it on nights where I've had a couple. Anyway, it's some relief to know that the reaction I had today isn't that uncommon, miserable as it is. I appreciate the tips on dealing with this strange medication and will continue to follow posts here...

  • Anonymous

    10/28/2010 4:51:40 AM |

    Great article Doc, thanks. I just flushed now, felt like a bad sunburn, and your water trick helped!

    I have been on Niaspan for a while, usually avoiding the flush with some tips from my heart Dr. He recommended two things that help me: take at bedtime, so if the flushing happens I am probably asleep, and also take my daily aspiring about 30 minutes before the Niaspan, which he says helps avoid the flush.

    Problem is, I usually end up taking the aspirin at the same time as the Niaspan for convenience, and that might not give thye aspirin enough time to help. Tonight, I took the pills at bedtime as usual, but ended up staying up later.

    One time when first on Niaspan, my heart raced like crazy with the flush, like another writer had. Anyway, thanks for great info.

  • Lemia

    12/20/2010 10:12:47 PM |

    Dr. Davis,
    Po"tay"to, Po"tah"to, with regards to allergy or sensitivity.  Particulary with lay people, if it causes an anaphalactic reaction (or even Hives, for that matter), might as well call it an allergy.  People also naturally need iodine in their bodies, and while "technically" you would say I have an iodine "sensitivity", that does not (and did not) stop me (nor many of my patients in the Cath Lab) from having an allergic reaction to IV iodine (and forget about topical betadine!)  

    To argue with someone about whether it is called an allergy or not, may give a non-medical person the idea that a sensitivity to something naturally occurring is therefore nothing to worry about.  In my case, and many others, it would mean death.  I think the nomenclature should be changed personally - if something can end up causing an anaphalactic reaction it SHOULD be called an allergy.

  • Lemia

    12/20/2010 10:14:34 PM |

    Correction: I meant to say "Anaphalactic reaction" and not "Allergic reaction"

  • Lemia

    12/20/2010 10:25:59 PM |

    As a side note:  I recently had what would be seen as a typical "allergic" reaction after taking just 250 Niacin - (this was Slo-Niacin) which I have been taking for years - as a matter of fact, I have gone down from 500mg.  Never had a problem with it before today.  Throat, tongue and lip swelling, wheezing, hives and a raised rash over full head and torso, front and back.

    My curiousity is over whether high levels of HDL itself may be a factor in such a severe reaction.  I already have an extremely high HDL and wondering if increasing an already high HDL was the culprit.  I would like to hear your thoughts on that and if you know of any such studies.  My own physician would like me on a statin, which besides giving me many side effects (all of them), I am doubtful as to their need with a normal ratio.  Despite having a high total cholesterol (ranging any given time from 275 to 325) , my ratio is absolutely fine.  Again, I am interested in hearing your thoughts on the subject.
    Thanks greatly.

  • Anonymous

    2/3/2011 3:49:55 AM |

    I am so relieved to read about others' experiences. I have been taking Niaspan 500mg for about 6 months with fairly mild flushing. Last night I had a severe reaction. I turned bright red, rapid heart rate, shortness of breath. I was burning up from the top of my head to the top of my thighs ( my legs were fine ). I am a RN and worked ER for 20 years and never knew that these symptoms could occur after many months of the same dosage. It was a relief to hear that it was not just me! I will continue to take the Niaspan but am taking the night off tonight!

  • Elizabeth Dugan

    2/27/2011 3:44:45 AM |

    I took Niacin (500mg) for a couple of days and am going insane with the itching.  I haven't taken it for 2 days now but I am still itching.  Does anyone know how long the Niacin stays in one's system?  Thank you.

  • Anonymous

    3/15/2011 4:25:50 AM |

    im twelve and my dad made me eat a i feel like im right in front of a 450 degree oven and i also feel like theres spikes protruding out of my body and my heart is beating like 5 time per secend

  • Anonymous

    3/30/2011 8:06:04 PM |

    The first time I took straight Niacin, not in a B-Complex, I got the flush severely. It actually started INSIDE my chest, it suddenly felt like there was cold water suddenly inside of my lungs, and I burst into a coughing fit. From there it spread. If it had stayed on my skin, it would have been fine. But it was inside my ears, and my whole sinuses puffed up so much I could barely breathe. I got VERY dizzy. I was on my way to the gym, and walked up 3 flights of stairs. By the time I got to the top of the stairs, my blood pressure had dropped so much I didn't make sense when talking, and then I promptly passed out. An ambulance was called, and after I came to and threw up, my BP was at some ridiculously low rate, like 55/40 or somewhere around there. VERY bad reaction, will not be taking again.

    And for those of you dismissing extreme reactors as "hypochondriacs", the flush is subjective, and how is passing out hypochondria?

  • Anonymous

    4/8/2011 12:26:17 AM |

    I have been taking niacin for years...I have found it to be the cure to brain know when you brain goes on vacation for like 3 seconds. I can't have that, I play bullet chess for several hours on end. That is where the whole game is played in a minute or less. Three seconds is an eternity. Anyway, I just had a massive flush; it happens once a year or so.  What usually triggers it for me is eating something with white bread.  They add niacin to it.  It is just enough to push me over the edge and instant beet.  You have to wait a few hours before having any white bread after taking niacin. Burger buns and pizza crust are the worst. It was Pizza this time. Intense exercise can also trigger it. But burger buns that is the biggie. I don't drink, so I have no familiarity with that interaction.
    One thing I did not see here is that afterword for a few days I feel really run down.  I either get the flush or not and when I do it is head to toe fire and itch, and I need several aspirin (I am 290 lb with a good deal of muscle)and lots of water and like three or more hours before it goes down.  I don't get a racing heart rate though. I don't want to cast any aspersions, but that sounds like panic ;). Oh, and scratching makes it worse for me, when it starts. I avoid that. I also sit down and do some mental relaxation exercises. I get dizzy if I stand up so I don't ;) I also think the shivering is just from having so much blood at the just pulls the heat from the core. I only shiver if I sit in front of a fan...still...I prefer the fan and shivers to fiery skin. But when I have not had access to a fan or cold water, I haven't had a shiver. I am not suggesting people take a lot of aspirin that is just me.
    Hmm, I like the dehydration explanation. When I exercise I do so intensely and for at least an hour...I suppose dehydration could be the reason exercise can trigger it in me.  I'll have to try extra water an hour before exercise. I may have been a little dehydrated this morning too as I awoke with both arms asleep and I was not sleeping on them. When that happens or if I have cramps when sleeping or on getting up, I have made the connection that I am generally dehydrated.

  • Anonymous

    4/9/2011 4:52:51 AM |

    I have been taking Niaspan for about 4 months. At first I had anxiety and flushing.  Now I just have the flushing and not daily. My doctor recommended that I take it with applesauce or apricots.  Pharmacist told my to take it with a low dose aspirin. Spicey food also seems to cause a reaction. I don't always get a flush and it only lasts about 20 minutes. My doctor also suggested I not use the aspirin because I won't get the full benefits. I am being monitored with blood tests and cholesterol is better. I also take Crestor.  I am a 51 year old post menopausal female with a family history of heart problems which I would like to avoid

  • Robin Ireland

    3/14/2012 3:34:40 PM |

    I stumbled upon a cure for the flush a few years ago. I was searching online and wound up at a drug reps site. Apparently one of their companies was doing a study on the Polyphenol Quercetin, and its natural ability to stop flushing. There were talks of combining Niacin with Quercetin to prevent it. So, being that it is a Polyphenol, and good for you, I thought I''d try it. It worked the very first time, and has worked for years since. I''ve been on up to 2G of Niaspan a day, and I take 2.5 G of Quercetin about 20 minutes beforehand and I almost never flush at all. If I do I just take a couple 500mg capsules of Quercetin and it goes away within 20 minutes. So, while I get a great dose of healthy Polyphenols I fight the flush too. I wish more people knew about this. Smile Just a word of wisdom though. Get the Quercetin alone. Some brands package it with Bromelain, which I found to upset my stomach over time.

  • Dr. William Davis

    3/16/2012 12:32:57 AM |

    Excellent find, Robin!

    You sure you need that much niacin, however?