Allergic reactions after coloring your hair; accidental ingestion
What are the symptoms of allergic reactions caused by oxidative hair dyes?
The main symptoms of allergic contact dermatitis, which is caused by an allergic reaction to oxidative hair dyes, are itching, redness, swelling, and bumps (papules or blisters) on the scalp, hairline, eyelids, forehead, behind the ears, neck, and other areas that come into direct contact with coloring mixture or rinse water.
Allergic contact dermatitis begins with an itching sensation in the 12 hours after application. It is followed by the onset of symptoms such as itching, redness, swelling, and bumps, with the most severe symptoms occurring 48 hours after application. If reactions are more severe, the entire face may swell, exudate may be emitted from your scalp, or the dermatitis may spread to areas that have not been in contact with the coloring mixture.
Continued use oxidative hair dyes despite developing such allergic reactions is dangerous, as the symptoms can become more severe and cause sudden and serious allergic reactions (generalized hives, difficulty breathing, drops in blood pressure, etc.).
Why do oxidative hair dyes sometimes cause an allergic reaction?
Oxidative hair dye contains oxidative dyestuff, alkaline agents, and hydrogen peroxide, which can cause reactions in some people. There are two types of reactions that can occur: irritant contact dermatitis and allergic contact dermatitis.
Which ingredients in oxidative hair dyes cause allergic reactions?
In the case of allergic contact dermatitis caused by oxidative hair dye, the cause is generally its active ingredients, oxidative dyestuff.
What kind of allergic reactions are caused by oxidative hair dyes?
Allergic reactions caused by oxidative hair dyes can be broadly classified into delayed hypersensitivity reactions and immediate hypersensitivity reactions.
Delayed hypersensitivity reactions typically begin with itching and other dermatitis symptoms in the 12 hours after application. Symptoms are the most severe 48 hours later.
Immediate hypersensitivity reactions are where severe symptoms such as generalized hives, difficulty breathing, and loss of consciousness due to low blood pressure occur suddenly during application or within 30 minutes after application. Immediate hypersensitivity reactions can be extremely dangerous.
Repeated use while failing to notice an allergic reaction after application, repeated use due to mild reactions, or reuse after reactions have subsided can gradually lead to severe reactions and, in rare cases, immediate hypersensitivity reactions.
What should I do if I develop an allergic reaction because of oxidative hair dye?
Discontinue use, wash off the coloring mixture, and seek immediate medical attention.
Do not leave the allergic reaction untreated or use any medications you may have on hand at your own discretion. When seeking medical attention, inform the doctor that you have used oxidative hair dyes. Whenever possible, bring the product you used with you. Medical attention should begin as soon as possible, as delays in proper treatment may result in prolonged symptoms.
I have experienced an allergic reaction because of oxidative hair dye in the past. What happens if I continue to use it?
Repeated use while failing to notice an allergic reaction following application, repeated use due to mild reactions, or reuse after reactions have subsided can be dangerous because your reactions can gradually become more severe. In rare cases, a serious allergic reaction known as anaphylaxis (generalized hives, difficulty breathing, etc.) may occur suddenly. Persons who have experienced allergic symptoms should never use any oxidative hair dyes.
I have experienced an allergic reaction because of oxidative hair dye in the past. Can I use a product from a different manufacturer?
Persons who have had reactions to oxidative hair dye should never use any oxidative hair dyes in the future.
In the case of allergic contact dermatitis caused by oxidative hair dyes, the cause is generally its active ingredient, oxidative dyestuff.
As oxidative dyestuffs are contained in all oxidative hair dyes, you should not use a product with a different color number or color shades or a product by a different brand or manufacturer. Try using a hair coloring product other than oxidative hair dyes, such as a hair manicure instead. Even if a product is intended for use at hair salons, you should not use oxidative hair dyes.
Why do hair bleaching agents and dye removers cause an allergic reaction?
Some hair bleaching agents and dye removers contain persulfates, which can cause allergic reactions in certain people.
What should I do if I develop an allergic reaction because of hair bleaching agents or dye removers?
Discontinue use, wash off the coloring mixture, and seek immediate medical attention.
Do not leave the allergic reaction untreated or use any medications you may have on hand at your own discretion.
When seeking medical attention, inform the doctor that you have used hair bleaching agents or dye removers. Whenever possible, bring the product you used with you.
Medical attention should begin as soon as possible, as delays in proper treatment may result in prolonged symptoms.
What should I do if I accidentally ingest oxidative hair dye, hair bleaching agents, or dye removers?
Because oxidative hair dyes and hair bleaching agents contain highly irritating ingredients, if any amount is swallowed, do not vomit. Rinse out your mouth, drink milk or water and seek medical attention at a nearby medical facility. Be sure to bring the product with you. Vomiting may risk injury to the esophagus or mouth. The oxidative hair dye may also accidentally enter the trachea. The recommended amount of milk or water to drink is 1–2 glasses (120–240 mL for adults or 15 mL or less per kg of body weight* for infants).
*Source: Japan Poison Information Center
Recommendation to color your hair
Can I use hair coloring products or hair bleaching agents on my child?
We recommend that children do not use hair coloring products or hair bleaching agents. Children are not able to judge their own scalp and skin conditions or accurately communicate them to their parents or guardians. It is also difficult to have children perform a skin allergy test (patch test) properly for oxidative hair dyes. A child’s scalp and hair are more sensitive than those of adults and are said to be more susceptible to irritation from alkalis.
I have a wound on my head, face, or neck. Can I still use hair coloring products or hair bleach agents?
You should not use hair coloring products or hair bleach agents.
Those with swelling, wounds, or skin diseases on their head, face, or neck are more susceptible to irritation. Do not use hair coloring products immediately after shaving your face, as the skin may be damaged and easily irritated.
Can I use hair coloring products if I have an illness, am recovering from an illness, am menstruating, or am pregnant?
You should not use hair coloring products.
If you have an illness, are recovering from an illness, are menstruating, or are pregnant, your skin and scalp are often hypersensitive and you may develop an allergic reaction. In addition, the medications used to treat allergic reactions during pregnancy may be limited and it may take a long time to heal.
Warnings and cautions at the time of use
Will hair coloring products color differently depending on my type of hair?
Softer and finer hair color more easily, while stiffer and thicker hair is more difficult to color.
The finished color greatly depends on your hair and your original color. Not everyone will see the same finished color. This is because different hair textures and damaged hair will react to hair coloring product and color differently. Therefore, it may be necessary to adjust how long you leave the coloring mixture on and the amount of coloring mixture you apply depending on your type of hair and how damaged it is. In addition, because coloring is difficult in colder environments, we recommend using hair coloring products somewhere with a temperature of 20-30°C
Which should I do first, color or perm my hair?
Choose the order that best suits the intended use of the product. However, to reduce the burden on your skin and hair, you should allow at least one week between hair coloring and perming.
When getting a perm after coloring your hair, the color will tend to come out and the finished color may fade or change. On the other hand, if you color your hair after getting a perm, the perm may come undone to a degree. Therefore, we recommend you choose the order that best suits your desired outcome, such as whether you want to put more emphasis on coloring or the perm. If you are having it done at a hair salon, please consult your beautician.
Is there a way to make it easier to remove the color mixture stains on my skin?
To make it easier to remove the color on your skin, we recommend that you apply an oil-based cream (such as cold cream) to the ears, hairline, and around your face before coloring your hair. If the coloring mixture gets on your hands or face, immediately wash it off with water or wipe it off with a moist cotton pad.
The instruction leaflet says not to apply to wet hair. Why not?
Wetting your hair before coloring may cause the coloring mixture to drip more easily and get into your eyes.
If a hair coloring product or a hair bleaching agent gets into your eyes, they can cause severe pain and in some cases damage your eyes (e.g., inflammation of the cornea), which is extremely dangerous.
The oxidative hair dye instruction leaflet says that the 1st agent (colorant) and 2nd Agent (oxidant) should be mixed just prior to use. Why is that?
When the 1st and 2nd agents are mixed, a color reaction begins. If the color reaction continues, it will lose its dyeability, so you should always mix the agents immediately before using them.
Where should I color or bleach my hair?
Some people may feel ill because of the smell, so we recommend coloring your hair in a well-ventilated area.
If the coloring mixture get on your clothes, floor, carpet, walls, it may not come off, so be careful. To prevent stains, we recommend that you cover the floor with newspaper.
Can I take a bath while coloring or bleaching my hair?
Do not take a bath with the coloring mixture in your hair, as perspiration or dripping may cause the solution to get into your eyes. Getting it in your eyes may cause severe pain, and in some cases may damage your eyes (inflammation of the cornea, etc.), which is extremely dangerous.
Also, when washing out the coloring mixture, be careful not to get it in your eyes.
What should I do if I feel sick while coloring or bleaching my hair?
Discontinue use, wash off the coloring mixture, and seek immediate medical attention. When seeking medical attention, bring the product you used with you whenever possible.
What should I do if the coloring mixture from a hair coloring product or a hair bleaching agent gets in my eyes?
If it gets in your eyes, do not rub your eyes. Immediately rinse thoroughly with cold or lukewarm water for at least 15 minutes. Seek medical attention from an ophthalmologist immediately. Also, when washing out the coloring mixture from your hair, be careful not to get it into your eyes.
What should I do if the mixture from a hair coloring product or a hair bleaching agent gets on my hands or face?
Do not rub forcefully; immediately wash the area gently with soap.
The coloring mixture on your hands or face becomes more difficult to remove as time passes. If the coloring mixture gets on your ears and hairline, wipe it off immediately with a moist cotton pad.
Can I color my hair with a hair coloring product and then color my eyebrows with it as well?
Hair coloring products and hair bleaching agents should not be used on eyebrows. These are for the hair on your head only. If you accidentally get a product in your eyes, it may cause severe pain and in some cases may damage your eyes (inflammation of the cornea, etc.), which is extremely dangerous.
The color of the 1st agent or coloring mixture from the oxidative hair dye is different from the finished color. Why is this?
The 1st agent or coloring mixture from the oxidative hair dye is not necessarily the same as the finished color.
Even if the color of the 1st agent or the color of the coloring mixture differs from that of the finished color, your hair should be colored like the finished color if you use the product correctly by following the instruction leaflet.
Will my hair color better or lighten more if I leave it longer after application?
The appropriate amount of time is included in the instruction leaflet for each product. Adjust the amount of time you leave in within that time range.
The result will vary from person to person depending on the thickness, stiffness, and degree of damage to your hair. Although leaving it in for a longer period of time will result in more colored or lightened hair, leaving it in longer than necessary may damage your hair and scalp.
If my hair does not turn out the way I want, can I color it again right away?
To avoid damaging your hair, we recommend allowing at least one week before coloring your hair again. Note that repeated use may damage your hair. We also recommend consulting a hair salon.
When I colored my hair, the skin on my hands and face was also stained. Is there a way to remove the stain?
Even if your skin stained because of oxidative hair dyes, hair color rinse, or hair manicure, it is stained only on the surface of your skin. Most of the stain can be removed by taking a bath, showering, or washing your hair several times. Do not try to remove it by rubbing forcefully, as this may damage the skin.
If I have any leftover mixture, can I store it until the next time I want to use it?
Leftover mixtures cannot be kept or stored. They will lose their ability to color or lighten hair. Also, if a container with leftover mixture is tightly closed, it may be dangerous because the pressure of the gas generated may cause the container to burst. Always wash off and dispose of any leftover mixture.
Can I save unused un-mixed agents?
Tube products (creams) can be stored if each is closed tightly with a cap and kept in a cool place away from direct sunlight. Single-use products should not be stored because they will lose their efficacy to dye hair.
Skin allergy tests
Why is a skin allergy test (patch test) needed before coloring my hair?
A skin allergy test is the most effective way to find out whether you will develop an allergic reaction when you color your hair. There is currently no known alternative testing method. To determine if you will have an allergic reaction, it is necessary to examine both reactions that occur soon after the test (immediate hypersensitivity reactions) and those that occur sometime later (delayed hypersensitivity reactions). It is therefore necessary to observe the test area twice, once about 30 minutes after application to the test area, and again 48 hours later. Perform a skin allergy test every time 48 hours before coloring your hair by following the instruction leaflet.
Why is a skin allergy test (patch test) needed every time before coloring my hair?
It is impossible to predict when allergic symptoms will occur, just as hay fever can develop suddenly. A skin allergy test is therefore needed each time.
I have never had dermatitis after coloring my hair. Is a skin allergy test (patch test) needed?
Yes, a skin allergy test (patch test) is needed.
Even those who have safely colored their hair numerous times in the past may suddenly develop allergic reactions one day, just as hay fever can develop suddenly. A skin allergy test should always be performed, even when using the same color number by the same manufacturer used in the past.
Skin allergy tests (patch tests) are annoying to perform. Is there an easier way to test?
Currently, there is no easy alternative to skin allergy tests.
A skin allergy test is currently the most effective way for customers to confirm in advance whether or not they will experience an allergic reaction when coloring their hair. To ensure safe use, perform a skin allergy test every time 48 hours before coloring your hair according to the instruction leaflet, even if it is annoying.
Why should I do a skin allergy test (patch test) 48 hours before coloring my hair?
To accurately determine whether you are not allergic to the product, it is necessary to observe the test area twice, once about 30 minutes after application to the test area, and again 48 hours later. Therefore, a skin allergy test should be done 48 hours before you plan to color your hair.
With a skin allergy test (patch test), why do I need to observe the test area twice, once after 30 minutes and once 48 hours later?
Two types of allergic symptoms are known: immediate hypersensitivity reactions, which occur during and/or immediately after applying, and delayed hypersensitivity reactions, which occur approximately 48 hours later after coloring. To be sure that neither allergic reaction occurs, it is necessary to observe the test area twice during a skin allergy test, once about 30 minutes after application to the test area and the other 48 hours later.
Can I take a bath or shower during the 48 hours of the skin allergy test (patch test)?
We recommend you not to take a bath or shower during the skin allergy test to avoid getting the test area wet.
For better results from the skin allergy test, you should not get the test area wet, rub the test area, or cover it with a bandage during this 48-hour period. If you must take a shower, be careful not to get the test area wet.
I performed a skin allergy test (patch test) and I experienced redness and itching, so I decided not to color my hair that day. Can I color my hair on a different day?
You should not color your hair with the hair coloring product you purchased, even when on a different day.
If a skin allergy test indicates skin reactions, you may be allergic to the product. Allergies like this are said to last your whole life, so once a reaction occurs, you should never use the same type of hair coloring product thereafter, even on a different day. Skin reactions observed at the test area of a skin allergy test (patch test) include itching, redness, a rash (papules or blisters), or swelling. Severe skin reactions may expand to areas around the test area.
I did a skin allergy test (patch test) and I experienced redness and itching, so I decided not to color my hair that day. Can I do the skin allergy test again on a different day and color my hair if I don’t experience any reactions?
If you ever experience any skin reactions with a skin allergy test, you should not use the hair coloring product you purchased, even if a test done on a different day does not result in a reaction.
If a skin allergy test ever indicates skin reactions, you may be allergic to the same type of hair coloring product. Even if a skin allergy test is done again on a different day and it does not result in any skin reactions, the product may cause an allergic reaction. Therefore, if you ever experience any skin reactions with a skin allergy test, never use any oxidative hair dyes. This includes different oxidative hair dyes for which skin allergy tests have not been done. Do not perform a skin allergy test either.
I have experienced an allergic reaction after coloring my hair in the past. Can I perform another skin allergy test (patch test) and color my hair if I do not observe any skin reactions?
Never use the same type of hair coloring product if you have ever developed an allergic reaction after coloring your hair with a particular product. Do not perform a skin allergy test either. If you ever develop an allergic reaction after coloring your hair, you may be allergic to it. The next time you color your hair, the dermatological symptoms may get worse, and you may experience a more severe allergic reaction.
What specific skin reactions occur with a skin allergy test (patch test)?
Itching and irritation may occur, as well as redness, swelling, or a rash (papules or blisters). In severe cases, reactions may also occur around the test area where the test solution was applied.
Fading and staining
How do I remove stains made by hair dye mixtures on clothes, the floor, carpet, walls, the sink, or the bathtub?
Be careful not to get it on clothes, the floor, carpet, or walls, as the coloring mixture will stain and become difficult to remove. If the coloring mixture does get on clothes, the floor, carpet, or walls, wipe it off quickly and wash the area with soap or another detergent. The more time passes, the harder it becomes to remove. Also, it may not be possible to remove it from some materials even if wiped off immediately.
We recommend that you cover the floor with newspaper when coloring your hair.
After coloring my hair, will the color come off in the rain or with sweat? Will the color stain my clothes?
Please note that using hair care products containing a lot of alcohol or sweating immediately after coloring your hair may cause the color to come out and stain clothes and/or pillowcases.
After coloring my hair with a color shampoo, color treatment, or hair manicure (semi-permanent hair dye), will the color come off in the rain or with sweat? Will the color stain my clothes?
Yes, the color may come off due to rain or sweat. Also, using large amounts of hair tonic, setting lotion, styling foam, or other hairstyling products can cause the color to come off.
After coloring my hair with a hair coloring spray, hair mascara, or other temporary hair dye, will the color come off in the rain or with sweat? Will the color stain my clothes?
Yes, the color will come off due to rain or sweat. Be careful not to stain your clothes.
After coloring my hair, if I sleep without drying my hair, will I get color on my pillowcase?
If you do not wash your hair thoroughly immediately after coloring, the dyestuff remaining on the surface of your hair may come off and stain your pillowcase and other bedding. Hair coloring manicures (semi-permanent hair dye) and hair coloring sprays and hair mascara (temporary hair dye) will come off with sweat and moisture left in the hair. After coloring your hair, shampoo your hair, use a hair conditioning product thoroughly, and dry your hair carefully before going to bed.
Will the color come off if I use hairstyling products or hair growth products?
Because the color may come off for several days after coloring your hair, we recommend that you check how the color comes off on an inconspicuous area before using the product.
Choosing suitable hair coloring products
What is the difference between gray hair dyes and fashionable hair dyes?
Gray hair dyes are made to match the color of gray and black hair, whereas fashionable hair dyes are made to be suitable for black hair or hair that is lighter in color.
Can I use fashionable hair dyes on gray hair?
Yes, you can. However, note that your result may differ from the desired finished color.
I have used hair color for women but would like to try using hair color for men. What is the difference?
If you like the finished color and ease of use of the product, you can use either products for men or women. For more information, please consult the manufacturer. There is no difference in the basic ingredients for both men’s and women’s products, but the color tones and fragrances may differ. In addition, because men tend to have shorter hair than women, many products for men use brushes, combs, and other application tools that are easier to use on shorter hair.
Can I use oxidative hair dyes on hair colored with hair manicure?
Yes, you can. However, it may be more difficult for dyestuff to penetrate into your hair. This may result in an uneven or poor-quality coloring. Depending on the number of times and amount of hair manicure used, you should shampoo your hair once every one to two days for three weeks to one month after coloring with hair manicure before using an oxidative hair dye.
I heard that there is a hair dye (cosmetics) with a plant ingredient called henna. What is it like?
Henna is a shrub in the Lythraceae family whose sun-dried leaves are used for coloring hair. There are documents proving it was used for coloring hair in Egypt and India more than two thousand years ago. If hair is colored with henna alone, the finished color will be light red to light brown. Even when using hair coloring products that contain henna as an ingredient, you should always perform a skin allergy test (patch test) every time according to the instruction leaflet.
In rare cases, henna products that color hair darker shades close to black, may be available. However, these products may contain other dyestuff or oxidative dyestuff, which can cause skin reactions in some people.
I hear that there are hair creams that color gray hair when exposed to light. What are these like?
There are hair creams for coloring gray hair containing silver salts, which gradually develop color and cover gray hair when repeatedly applied to the hair and exposed to light. Please note that if oxidative hair dye is applied to hair that has been treated with such products, both the silver salts and the oxidative dyestuff will become discolored, and the hair may not be colored to the desired outcome.