Most people think a 10% niacinamide serum is the fastest way to clear pores and stop breakouts. I thought the same thing. So I bought a bottle of The Ordinary Niacinamide 10% + Zinc 1% Serum ($6.50, 30ml) and used it every single morning for 30 days. Here is exactly what happened — the good, the bad, and the unexpected.
Day 1 to Day 7: The Purging Phase Nobody Talks About
I applied two drops to clean, damp skin every morning. No other new products. By day 3, my chin erupted. Not a full breakout — just four small, red bumps that looked like clogged pores pushing up.
What niacinamide actually does to your skin
Niacinamide (vitamin B3) works by increasing ceramide production and calming inflammation. At 10%, it also speeds up cell turnover. That turnover pushes existing congestion to the surface fast. This is not a bad reaction — it is the serum working. But nobody warns you about it.
By day 7, those bumps flattened. My skin texture on my nose looked smoother. No irritation, no stinging. Just a few days of minor purging.
The texture issue
The serum has a slightly tacky, gel-like feel. It dries down in about 90 seconds, but if you layer moisturizer too fast, it pills. I learned to wait 2 full minutes before applying CeraVe Moisturizing Cream ($16, 539ml). After that, no pilling.
Week 2: Oil Control Kicked In — But Not For Everyone
By day 10, my T-zone looked noticeably less shiny by 2 PM. Normally, I blot twice during the workday. During week 2, I blotted once. That is a 50% reduction in visible oil.
But here is the catch: if you have dry or dehydrated skin, this serum can feel tight. My cheeks, which are normal-to-dry, felt slightly pulled after 4 hours. I had to switch to a richer moisturizer on those areas — La Roche-Posay Cicaplast Baume B5 ($16, 40ml) — to balance it out.
Who should NOT use this serum
- Dry skin types using it all over the face without a heavy moisturizer
- Anyone with active, broken skin (niacinamide can sting on wounds)
- People sensitive to zinc — it can cause mild flaking in some users
For oily and combination skin, this is a solid oil-control tool. For dry skin, look for a 5% niacinamide formula instead — like Paula’s Choice 10% Niacinamide Booster ($44, 20ml) which has a more hydrating base.
Week 3: Pore Size — The Real Test
Pores do not open and close. They stretch out when filled with oil and debris. Reducing that oil keeps them looking smaller.
By day 18, my nose pores looked visibly less noticeable. Not gone. But the dots that usually showed through makeup were 60% less visible. This is the serum’s strongest benefit in my opinion.
How I applied it for maximum pore results
- Cleanse with La Roche-Posay Toleriane Purifying Foaming Cleanser ($15, 200ml)
- Pat face damp — not dry
- Apply 2 drops of serum to nose, chin, and forehead only
- Wait 2 minutes
- Apply moisturizer
Using it on damp skin helped spread the thin formula more evenly and reduced the tacky feeling.
Week 4: Breakout Reduction — The Numbers
| Week | Active breakouts | New breakouts | Oil blotting sessions per day |
|---|---|---|---|
| Baseline | 3–4 | 1–2 per week | 2 |
| Week 1 | 5 (purging) | 4 | 2 |
| Week 2 | 2 | 1 | 1 |
| Week 3 | 1 | 0 | 1 |
| Week 4 | 0 | 0 | 0–1 |
By day 28, I had zero active breakouts for the first time in 6 months. No new cysts. No whiteheads. My skin stayed calm even during my period — which normally triggers at least one deep pimple.
This serum is not a spot treatment. It prevents breakouts by controlling oil and reducing inflammation over time. If you have cystic acne, this alone will not clear it. You likely need prescription retinoids or benzoyl peroxide.
Two Common Mistakes That Ruin Results
I see these mistakes in skincare forums constantly. They make the serum less effective or cause irritation.
Mistake 1: Mixing with vitamin C in the same routine
Niacinamide and vitamin C do not cancel each other out. But applying both at once can cause flushing in sensitive skin. I used Timeless Vitamin C Serum ($25, 30ml) in the morning and this serum at night. Zero issues. Do not layer them together — alternate AM/PM instead.
Mistake 2: Using too much
More than 3 drops is wasteful. The serum spreads easily. I used 2 drops total for my entire face. Using 4+ drops caused pilling and a sticky film that caught lint from my pillow.
Week 5 (Bonus): What Happened When I Stopped
I stopped using the serum for 5 days after the 30-day mark. By day 3, my oil production returned to baseline. By day 5, I had one new small whitehead on my chin.
This tells me the serum works by actively managing oil day-to-day. It does not permanently change your skin. You need to keep using it to maintain results.
If you stop, the oil comes back within 72 hours. Plan to use this as a maintenance product, not a fix-it-once solution.
Final Verdict: Worth It or Skip It?
For oily, combination, or acne-prone skin: buy it. At $6.50 per bottle, it is the most cost-effective oil-control serum available. It reduced my breakouts to zero, shrunk pore appearance by 60%, and cut oil production in half.
For dry, sensitive, or rosacea-prone skin: skip it. The 10% concentration is too high for you. Try The Ordinary Niacinamide 5% + HA ($7.50, 30ml) instead — it has a gentler dose plus hyaluronic acid for hydration.
The serum is not a miracle. It will not erase scars, fix hormonal acne, or replace sunscreen. But for exactly what it claims to do — reduce oil, refine pores, and calm breakouts — it delivers. That is rare for a $6 product.