Niacin Flush Explained: Why Your Skin Turns Red and What to Do
What it is
Nicotinic acid triggers release of prostaglandins that dilate skin blood vessels, producing warmth, redness and itching on the face and chest. Nicotinamide does not usually cause it. The seller does not state which form HoneyPezil uses; read the bottle.
How long it lasts
Usually 15 to 30 minutes after a dose and often fades with regular use. It is not an allergy.
The upper limit
The NIH Office of Dietary Supplements sets the tolerable upper intake at 35 mg a day for adults from supplements and fortified foods, mainly because of flushing. Prescription niacin uses far larger amounts under medical supervision and carries liver and other risks.
Ways to reduce flushing
- Take with a meal or water.
- Avoid hot drinks and alcohol around the dose.
- Talk to a clinician before taking aspirin for it.
- Discuss lower-flush forms if you flush often.
When it is not just a flush
Seek care for hives, swelling of lips or face, trouble breathing, dizziness, jaundice or dark urine.
Medicine and condition cautions
People with liver disease, gout, ulcers, diabetes, or on statins or blood-pressure medicine should ask first.
Flush versus allergy
A flush starts within minutes, affects the face and chest and fades; an allergic reaction may cause hives, swelling, wheeze or faintness and requires urgent care. If you cannot tell the difference, treat it as an allergy and seek help.
Why different forms behave differently
Nicotinic acid triggers flushing; nicotinamide generally does not; inositol hexanicotinate is marketed as "no-flush" with debated effects. The seller does not say which form HoneyPezil uses, so check the label.
Doses to be careful about
The upper limit for supplements is 35 mg a day in adults. Higher amounts are used only under medical supervision for blood lipids and can affect the liver, blood sugar and uric acid. See the ODS fact sheet.
Timing and triggers
Hot showers, spicy food, alcohol and exercise around the dose can amplify flushing. Taking the capsule with food and water tends to soften it.
Tolerance
Flushing often lessens within weeks of regular use, though not for everyone.
Know your form
If flushing bothers you, ask the seller which form of niacin is used and discuss alternatives with your clinician, rather than buying a different high-dose niacin product on your own.
What to do during a flush
Sit or lie down, drink water, avoid hot drinks and alcohol, loosen tight clothing and wait. It usually fades in under half an hour. Note the time after the dose and what you ate. If you flush every day and dislike it, ask the seller about the niacin form and talk to your clinician about alternatives. Do not respond by taking more aspirin or other products without advice. Seek urgent care if you have difficulty breathing, facial swelling, hives, chest pain or fainting. Over several weeks, track whether flushing lessens. If it persists or worsens, stop and ask for medical advice. Keep the label amount in mind and avoid additional niacin from other supplements while you work out the cause.
Frequently asked questions
Sources
General information, not medical advice. Offer details were checked on November 10, 2026; confirm on the order page and read the label on your bottle. See our disclaimer and how we research.