
The hair and beard dyes of today—whether chemical- or plant-based—are safer than those of even the 1980s and are generally well-studied by experts (including via the Hair Dye Substance Database); longer-term study results of some of the more problematic ingredients are pending.
Many of these additives are also regulated by the Food and Drug Administration (FDA) in the United States. Although “organic” hair dye is a myth, in that even plant-based henna, cassia, and indigo extracts contain heavy metals leached from the soil, it is possible to be both safe and environmentally conscious about hair-dye use, down to time of contact. (Source)
Chemists and colorists alike offer many safety tips, including never wearing any hair dye (except permanent) overnight, because of health issues (e.g., eye or skin irritation) and permanent staining of bedding or clothing. Safety experts recommend reading the ingredients prior to use and staying away from problematic chemicals such as ammonia and paraphenylenediamine.
Other hair-dye safety tips include the following:
- Do a 24- or 48-hour behind-the-ear patch test for skin sensitivity before first use; proceed only if no skin or eye irritation results (Source)
- Wear gloves and an old shirt while applying. You can also wrap your neck and safeguard your floor preparation area with old towels
- Before application, rub petroleum jelly as a barrier around the hairline
- Use a brush for precise, safe dye application, and don’t mix dyes unless you’re very experienced
- Forgo coloring for as long as you can. If you do decide to dye, leave either natural or inorganic/chemical hair dye in for as short a duration as possible per the instructions (Source)
- Rinse your scalp with cold water after dye use (Source)
How Long Can You Leave Semi-Permanent Hair Dye in?
Follow the directions for time to leave in semi-permanent hair dye, whether you use a boxed dye or something from your salon. L’Oréal Paris offers this advice for its Colorista Semi-Permanent Hair Color: “You should leave the dye on your strands for 15 to 30 minutes.” This Sally Beauty Pro-Colorist mostly concurs, recommending that you “allow the [semi-permanent dye] color to sit for at least 30 minutes” then rinsing your hair “until it runs clear.”
What if you don’t have instructions or know what type of dye you have? The chemist behind Lab Muffin Science explains how temporary, semi-permanent, and permanent hair dyes work: “The difference between permanent and temporary dye is the all-important cuticle opening/closing process. With temporary dyes, the cuticle isn’t opened. . . . Semi-permanent dyes open the cuticle slightly.” (Source)
Also, semi-permanent dyes, unlike permanent, do not contain the often-cited-as-problematic chemicals ammonia or peroxide. (Source)
Can You Leave Arctic Fox Hair Dye in Overnight?
The makers of Arctic Fox say that its various shades will not harm your hair, even if left on for longer than the recommended time, which is at least 30 minutes. They write that their hair color “has added conditioner, so leaving it on for longer will not hurt a thing.” (Source)
However, they also offer the following tips, which indicate NOT leaving the dye in overnight: “Rinse hair in tepid H2O thoroughly, until the water runs clear. . . . To prevent color bleeding, make sure hair is completely dry before sleeping.”
I personally love using Artic Fox Hair Dye to color my hair. I always find the cheapest price on Amazon – Artic Fox Hair Dye.
Can you Leave Manic Panic in Your Hair Overnight?
Both the company that makes Manic Panic and regular users say it can transfer to bedding. “I used Manic Panic for a while when I first started out, but it transfers to my pillow so easily.” (Source)
As for Manic Panic Amplified Spray, the directions are pretty explicit that it should never be worn overnight: “Be sure to wash your hair thoroughly before going to bed to avoid staining your linens & fabrics”. They are also careful to advise doing a patch test before first use and NEVER applying it to eyebrows or lashes because it could cause blindness. (Source)
Does Hair Dye Get Darker the Longer You Leave It in?

The easy answer is that it depends on the type of dye. Professional stylist Chelsey Pickthorn notes that progressive dyes by their nature “keep getting darker and darker” as they stay on. (Source)
Leaving dye in/on too long is a common issue seen in the salon. According to styling expert Tabitha Mitchell, this typical at-home mistake could create dry, brittle—that is, damaged—hair. (Source)
The key with darkening is understanding that your hair will not turn out like the photograph on the packaging, and that many instructions are written for the hair of Caucasians. Jaxcee, the color director of Hair Rules, says you should manage your expectations by understanding what your base hair color is and what it’s likely to become via coloring.
“For someone who wants to do their hair at home, you definitely have to pay attention to how dark your hair is and realize that you’re probably not going to get a result that is any more than three levels lighter than your hair, if you’re trying to lift it.” (Source)
Likewise, if your hair comes out too dark, you probably should not try to correct it at home. Colorist Leanne Chadwick notes that you cannot lighten up a really dark shade by coloring it again with another, lighter shade.(Source)
How to Prevent Hair Dye from Bleeding on Your Pillow

Again, you should always read the instructions included with your dye. Chances are good they will tell you how to minimize discoloration to your clothing and area where you apply the coloring (e.g., using old or dark-colored towels, as Lab Muffin recommends, or plastic-wrapping the sink, except the drain, as well as how to prevent skin or eye irritation. (Source)
Some dyes—e.g., Manic Panic—are widely reported as transferring stains to bedding, and the manufacturers themselves are up-front about this risk. Take steps, then, to never leave any dye, other than permanent, in your hair overnight.
You might also try applying a cap over dyed hair, but those who are active sleepers report that caps or towels fall off or have gotten tangled in bed—with bedding still getting stained. Another tip that might work for you, however, is to sleep with a towel or T-shirt over your pillowcase. (Source)
I personally recommend using a waterproof pillowcase to help protect my pillows & pillowcases from getting ruined. Here is the one I’ve been using for a few years – UltraPlush Premium Waterproof Pillow Protectors (link to Amazon).
Connect with a Colorist
With hair-coloring comes a lot of questions, and we can’t answer them all here. But there’s hair help on the way in the form of a sparkly new start-up from L’Oréal. Color&Co promises technology that connects you with pro-colorists who will help you to build a custom hair color at home that will be direct-mailed to you. The consultation is free, but the dye will cost you, of course! (Hair Consultation)
Dye on the Hair-izon
Someday we might all be able to use artificial melanin on our hair. “Scientists . . . have developed a new type of hair dye that could be healthier than traditional chemical hair dyes known to cause allergic reactions, swelling, and a potential increased risk for cancer in some people.” (Source)
Wouldn’t that be a hair-raising breakthrough?