Niacinamide Side Effects
For the Consumer
Applies to niacinamide: tablets
Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur while taking niacinamide:
Diarrhea; dizziness; headache; itching; nausea; stomach upset; temporary feeling of warmth or flushing of the skin.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); black, tarry, or bloody stools; changes in vision; dark urine; decreased urination; fast or irregular heartbeat; loss of appetite; muscle pain or weakness; numbness or persistent tingling of the skin; persistent nausea, vomiting, or general "unwell" feeling; severe or prolonged flushing of the skin; stomach pain; swelling of the hands, legs, or feet; vomit that looks like coffee grounds; yellowing of the skin or eyes.
For Healthcare Professionals
Applies to niacinamide: compounding powder, oral tablet
Cardiovascular side effects are rare and mild and have included tachycardia.[Ref]
Metabolic side effects have included hyperglycemia and hyperuricemia.[Ref]
Nervous system side effects have included headache.[Ref]
Gastrointestinal side effects have included bloating, flatulence, diarrhea, stomach upset, and nausea.[Ref]
Dermatologic side effects have included increased sebaceous gland activity, dry skin, itching, and rash.[Ref]
1. Baumgartner TG, ed. "Clinical Guide to Parenteral Micronutrition." Gainsville, FL: Fujisawa (1991):
2. Sugar AM, Liu XP "Efficacy of voriconazole in treatment of murine pulmonary blastomycosis." Antimicrob Agents Chemother 45 (2001): 601-4
It is possible that some side effects of niacinamide may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.
More about niacinamide
- Side Effects
- During Pregnancy
- Drug Interactions
- Support Group
- 1 Review – Add your own review/rating
- Drug class: vitamins
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