Colgate’s Optic White Express Pen is one of the best-selling whitening pens on the market, but for many users, the results fall far short of expectations.

While the brand claims you can see results in just one day, most users saw little to no difference even after completing the full 7-day regimen. The pen contains a hydrogen peroxide gel and features a precision applicator, but the formula tends to rub off easily before it can do much whitening — especially once your lips touch your teeth.

Even though it’s advertised as enamel-safe and sensitivity-free, multiple testers reported burning, lip irritation, and heightened tooth sensitivity after using it.

If you’re hoping for fast, effective, and hassle-free whitening, this pen likely won’t deliver.

The Moon Whitening Pen, promises a premium whitening experience with a sleek, minimalist look. It features a vegan formula with urea peroxide, light-reflecting pigments, and natural extracts like strawberry, lavender, and honeysuckle.

Despite its elegant packaging, the actual whitening performance was underwhelming. Users consistently reported minimal to no results even after consistent use. Several reviewers complained that the pen dispensed little to no product, requiring excessive clicks for just a trace of gel. Others noted that even when applied correctly, the formula rubbed off quickly or failed to make any visible change.

While the pen is marketed as gentle, some users experienced gum irritation. Add in the bitter taste and high price for what amounts to only a few applications, and it’s clear this pen falls short of expectations.

If you’re looking for noticeable whitening, Moon’s pen is more aesthetic than effective.

Crest is one of the most trusted names in oral care, but this whitening pen fails to deliver on its promise. While the product is marketed as quick, easy, and enamel-safe, many users found the whitening results minimal at best, even after a full week of consistent use.

One of the biggest frustrations is the application. The gel is difficult to apply evenly, and keeping your mouth open for 60 seconds while avoiding saliva contact is harder than it sounds. Many users reported the gel sliding off their teeth, drying poorly, or being accidentally swallowed. Several reviews also noted that the twist mechanism was unreliable, and the pen often ran out after just a few uses.

While it may work as a mild touch-up tool for people who already have white teeth, Crest’s pen simply doesn’t live up to its name for anyone seeking visible results.

ARC’s whitening pen looks like a smart and affordable choice on the surface. It features a precision brush tip and hydrogen peroxide formula, all packed into a sleek, travel-sized applicator under $10.

But for many users, that’s where the positives end.

Multiple reviewers described frustrating experiences with leaking pens, broken twist mechanisms, and inconsistent texture. Instead of a whitening gel, some users received a watery liquid that failed to stick to the teeth. Others reported barely any gel coming out at all or the pen being nearly empty from the start.

Even when it worked, the whitening results were faint and short-lived. Several users said it left a chalky or cakey film on their teeth that faded within hours. While marketed as gentle, it failed to make a visible difference for those with moderate or deeper stains.

ARC may be cheap and portable, but the quality control and whitening power just aren’t there.

Lumineux offers a peroxide-free, plant-based whitening pen powered by coconut oil, Dead Sea salt, sage oil, and lemon peel. The pen works in two modes: stain repellent (apply 60 seconds before meals) or whiten (leave on for 30 minutes). It’s crafted for sensitive users and designed to protect enamel while brightening teeth.

Some users reported visible brightening within 3‑7 days and no sensitivity, a win for mild cases. The application process is simple: twist to dispense gel, brush two coats, and wait. The dual-function makes it flexible for both whitening and stain prevention.

However, reviewers consistently noted the results are mild and slower than peroxide-based pens. A few users mentioned mold growth on the brush after several uses, raising concerns about packaging and hygiene. Others on Reddit criticized poor adhesion and goopy residue that required brushing off.

Lumineux is a gentle, clean-label option for everyday maintenance or rinsing before a coffee. But for deeper stains or faster whitening, stronger options like ShinePen remain more effective.

Snow’s pen is part of the DiamondSeries whitening system that includes enamel-strengthening ingredients like hydroxyapatite and potassium nitrate. The pen is designed for precision application, often paired with Snow’s LED mouthpiece kits, though the pen itself can be used separately for spot touch-ups.

When used with the LED kit, testers noticed a visible improvement of one to two shades after a few uses, and reported minimal sensitivity. As a standalone pen, it provides light surface stain removal, but without the light activation, results were more modest and slow to appear.

Though Snow promotes it as part of a complete system, users who purchased only the pen noted that results were seasonal and not long-lasting unless used regularly. There were also remarks that instructions were confusing and that the pen didn’t deliver the dramatic results seen in clinical tests.