Which B Vitamins Cause Acne? And What to Do If It Won't Stop
Short answer: vitamin B12 is the B vitamin most clearly linked to breakouts, especially at high doses or as injections. Vitamin B6 has been reported alongside it, and biotin (B7) is one of the most common supplements people suspect. If you started breaking out after a new supplement, it may be part of the picture. But acne is different for everyone, and a breakout that doesn't settle once you adjust your supplements usually points to something internal, like hormones or blood sugar. The only way to know what's driving your acne is to test.
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Why B vitamins matter for your skin
Most people take B vitamins for a reason: they feel tired and suspect a deficiency, a "hair, skin and nails" blend promised better skin, or a B-complex came in a supplement made for acne. A B-complex is in fact one of the most common ingredients in supplements marketed for acne (Vaidya et al., 2024).
That's the catch. Supplements are often a guess at what your body needs. Sometimes the guess adds a trigger. And sometimes it covers up the real question: why your skin was struggling in the first place.
Which vitamin B causes acne?
Here's how each B vitamin relates to breakouts.
| B vitamin | Link to breakouts | What's been reported |
|---|---|---|
| B12 (cobalamin) | Can trigger sudden, uniform breakouts | Case reports going back decades, mostly with high doses or injections, plus a study showing how B12 changes acne bacteria |
| B6 (pyridoxine) | Flares or an acne-like rash | Reported in patients taking B6, often together with B12 |
| B7 (biotin) | Widely suspected | Many personal reports, with a popular theory that high doses compete with B5 |
| B5 (pantothenic acid) | Sold for acne | One small trial found fewer lesions than placebo |
| B3 (niacinamide) | Used on the skin for acne | A common topical skincare ingredient |
Does B12 cause acne?
It can, and there's a clear reason why. A 2015 study found that when healthy volunteers took B12, the acne-linked skin bacterium C. acnes changed its activity. In lab cultures, extra B12 pushed the bacteria to make more porphyrins, compounds that drive inflammation in acne. One of the ten volunteers broke out about a week after starting B12 (Kang et al., 2015).
Case reports describe the same pattern, mostly in people on high-dose shots for a deficiency (Owen et al., 2025; Bahbouhi et al., 2023). Many people take B12 with no change at all, which is exactly the point: how your skin responds depends on you. For more, read our guide to vitamin B12 and acne.
What does B12 acne look like?
Vitamin-triggered acne tends to look different from everyday acne (Braun-Falco and Lincke, 1976; Kazandjieva and Tsankov, 2017; Owen et al., 2025):
- It starts suddenly, after a new supplement or shot.
- The bumps all look alike: small red papules and pus bumps.
- Blackheads and cysts are usually missing.
- It can spread beyond the usual spots, onto the forehead, chin, chest, back and upper arms.
- Some cases itch, which is less typical of ordinary acne (Bahbouhi et al., 2023).
If your breakouts look like this and started soon after a new product, a supplement is a strong suspect. If they look like your usual acne, the cause is likely deeper.
Does vitamin B6 cause acne?
It's been reported. German dermatologists described 14 patients whose acne worsened, or who developed an acne-like rash, while taking vitamin B6 and/or B12. Most were women, and the rash generally faded soon after the vitamins were stopped (Braun-Falco and Lincke, 1976). Because B6 so often comes packaged with B12, it's worth checking both doses on your labels.
Does biotin cause pimples?
Biotin is one of the supplements people most often suspect, usually from a "hair, skin and nails" blend. The popular theory is that a large biotin dose competes with vitamin B5 for absorption, and that this can affect the skin. If your skin changed after starting biotin, the timing is worth writing down.
One practical point: biotin can interfere with some blood tests, including vitamin D, so tell whoever runs your bloodwork that you take it (Shing et al., 2025).
Wait, isn't vitamin B5 sold for acne?
Yes. In a 12-week trial of 41 adults, a pantothenic acid-based supplement reduced lesion counts more than placebo (Yang et al., 2014). And niacinamide (B3) is a familiar acne skincare ingredient. To check a product for niacinamide or common pore-cloggers, paste its ingredient list into our free acne-safe ingredient checker. So "B vitamins cause acne" is too broad. It's mainly about B12, and how your body responds.
B-complex and multivitamins: the stacking problem
B-complexes usually contain B12 and B6, the two B vitamins with acne reports. The bigger issue is stacking. Many people take several products that each contain B12 and never add them up:
- A multivitamin
- A B-complex or "energy" supplement
- Energy drinks or shots
- A "hair, skin and nails" blend
- B12 injections or high-dose sublingual B12
The published cases mostly involve high doses or injections, so list everything you take and add up the B12 and B6. Our guide to supplements that can cause acne covers other common triggers.
How long does B12 acne take to go away?
Case reports are the best guide. In the 1976 series, the rash generally faded within a short time once the B6 or B12 was stopped (Braun-Falco and Lincke, 1976). In a more severe 2023 case, the breakout began 6 weeks after weekly B12 injections started and cleared within 3 months after they stopped, with acne treatment added (Bahbouhi et al., 2023). Reviews of drug-induced acne agree that removing the trigger should lead to improvement (Kazandjieva and Tsankov, 2017).
A reasonable expectation is a few weeks for a mild flare and up to a few months for a severe one.
Still breaking out weeks after you cut back?
Then the supplement probably wasn't the whole story. Persistent acne can trace back to hormones, blood sugar swings or low vitamin D, and you can't see any of those in the mirror. BreakoutLabs checks them from home in one sample.
What to do if you think a B vitamin is breaking you out
- List everything with doses. Include drinks, shots and blends, not just bottles labeled "vitamin B".
- Line up the dates. A sudden crop of look-alike bumps within days to weeks of starting something is the classic pattern.
- Don't stop prescribed B12 on your own. If you get B12 for a deficiency, you need it. Your doctor can adjust the dose or treat the breakout.
- If acne was there before the supplement, or doesn't settle after, test. A vitamin can make acne worse without being the reason you have it.
Why test with BreakoutLabs
A supplement trigger is something you work out from your labels and your timeline. What's underneath your acne is something you can only see in your blood. The BreakoutLabs Acne Root Cause Test checks the internal drivers that matter most for acne: hormones, blood sugar, metabolism and vitamin D.
You could ask your doctor for bloodwork, but that usually means booking an appointment, getting a lab slip, traveling to a lab for a needle draw, and waiting for results that aren't read with your acne in mind. BreakoutLabs is built for one question: what's driving your breakouts.
- At home, no lab visit: a painless device on your upper arm, no appointment needed.
- 19 biomarkers across hormones, blood sugar, metabolism and nutrients, including Free and Total Testosterone, SHBG, DHEA-S, HbA1c and Vitamin D.
- Results in 5 business days after the lab receives your sample.
- A personalized Clear Skin Blueprint that explains your results for your skin.
- $199, HSA/FSA eligible, and backed by our 30-day guarantee.
Get your Acne Root Cause Test →
Frequently asked questions
What does B12 acne look like?
Usually a sudden crop of small, similar-looking red bumps and pus bumps, with few or no blackheads. It often shows up on the forehead, chin, chest or back within days to weeks of starting high-dose B12.
How long does B12 acne take to go away?
In published cases, it fades after the high dose stops, often within a few weeks. One severe case took about 3 months to clear with treatment. If it doesn't settle, look for an internal driver.
Does the BreakoutLabs test measure B vitamins?
No. It checks hormones, blood sugar, metabolism and vitamin D, the internal drivers that matter most for acne. Supplement triggers are best worked out from your labels and timeline.
Sources
- Kang D, Shi B, Erfe MC, Craft N, Li H. Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis. Science Translational Medicine. 2015.
- Braun-Falco O, Lincke H. The problem of vitamin B6/B12 acne. A contribution on acne medicamentosa. MMW Münchener Medizinische Wochenschrift. 1976.
- Owen JJ, Youssef RM, Altman K. Vitamin B12-induced acneiform eruption. Baylor University Medical Center Proceedings. 2025.
- Bahbouhi I, Aboudourib M, Hocar O, Amal S. Vitamin B12 induced acneiform eruption. Heliyon. 2023.
- Kazandjieva J, Tsankov N. Drug-induced acne. Clinics in Dermatology. 2017.
- Shing V, Aragon Sierra A, Shah AA. Benefits and risks of hair, skin, and nail supplements in older adults. International Journal of Women's Dermatology. 2025.
- Yang M, Moclair B, Hatcher V, et al. A randomized, double-blind, placebo-controlled study of a novel pantothenic acid-based dietary supplement in subjects with mild to moderate facial acne. Dermatology and Therapy. 2014.
- Vaidya T, Hoffman L, Chapas A. Evaluating common ingredients contained in dietary acne supplements: an evidence-based review. Journal of Clinical and Aesthetic Dermatology. 2024.
This article is for educational purposes and is not medical advice. Talk to your healthcare provider about testing and treatment.
