Introduction

A tattoo ink allergy happens when an individual is allergic to the tattoo pigment, mostly commonly occurring when red pigments are used.¹ However, this does not mean that a tattoo ink allergy only occurs due to red pigments. The allergy has been reported due to other pigments, including yellow, green, violet and purple.¹ Approximately 10% of those who receive a tattoo report an adverse reaction, which can include itching, swelling or rash formation. 

Typically, allergic reactions to tattoo pigments are uncommon, with 90% of individuals experiencing no adverse reaction. This lack of reactions is due to the ink pigment quickly becoming encapsulated in fibrous tissue, where it becomes less reactive and therefore the chances of an allergic reaction are much lower.²  

In the following sections, we will explore how such reactions take place.

Types of tattoo ink allergy

Immediate hypersensitivity

Immediate hypersensitivity is described as an immune response to the allergen, which in this case is the tattoo ink ingredients, and occurs within minutes of exposure to the allergen.³ Here, the body recognises the tattoo ink ingredients as foreign to the body, in a similar manner as if a threat such as a virus were present within the body.

Symptoms of immediate hypersensitivity include:

• Sneezing
• Nasal congestion
• Coughing
• Skin rashes
• Watery eyes
• Swelling of the face, lips and tongue

These ingredients in tattoo ink can cause immediate hypersensitivity:

• Aluminium
• Brazilwood
• Cadmium sulfide
• Iron oxide

Delayed hypersensitivity

Delayed hypersensitivity is also described as an immune response to tattoo ink ingredients, and is similar to immediate hypersensitivity. The way it differs from immediate hypersensitivity is that this type of allergic reaction usually occurs 12 hours after exposure to the allergen, but it can also occur later than that.⁴ Delayed hypersensitivity reactions include contact dermatitis.

Symptoms of delayed hypersensitivity include:

• Fever
• Wheezing
• Angioedema

Causes include:

• The impact of sun exposure to the tattoo ink over time may induce the photochemical breakdown of tattoo pigments. This typically occurs with yellow pigments.
• Metabolism of a tattoo pigment over time.

Risk factors

Ink composition

Different tattoo inks are composed of colourants, which can be either organic or inorganic pigments. These pigments can be responsible for delayed hypersensitive reactions that are seen with tattoo ink allergy, due to the organic pigments slowly degrading, and releasing products which may act as potential allergens.⁵ 

Heavy metals present in tattoo ink, such as cadmium and mercury, are associated with causing allergic reactions.⁵ Mercury is particularly potent in red ink, with red ink inducing the most allergic reactions.⁵ Cadmium is present in yellow ink and is responsible for photo-toxic reactions when in contact with the sun.⁶

Skin sensitivity

Skin sensitivity, which may be caused by skin conditions such as eczema and psoriasis, can cause an increased risk of tattoo ink allergy.

Tattoo aftercare

Allergic contact dermatitis can be also contracted from applying scented lotions to a healing tattoo.⁷ Scented lotions contain potential allergens, which can result in the healing tattoo also developing an allergic reaction.⁷ Photoallergic reactions can occur due to tattoo overexposure to sunlight.⁸ This is particularly common with yellow-pigmented tattoos.⁸ 

Therefore tattoo aftercare should involve avoiding sunlight and scented lotions. If sunlight exposure cannot be avoided for fresh tattoos, sun lotion should not be applied either, as you have to remember that a fresh tattoo is an open wound, and it would therefore be exposed to chemicals and minerals that could cause damage.

Diagnosis

Clinical examinations can reveal the following features which indicate an allergic reaction to tattoo ink:⁹

• Looking for ulcerations on the skin that has been tattooed
• Appearance of sarcoidosis
• Flattened popular lesions
• Eczematous lesions

Challenges in establishing a diagnosis

Establishing a diagnosis is difficult as the different clinical lesions are non-specific.⁹ Therefore the doctor may look at a variety of factors when looking for a diagnosis, including medical history questions and questions about the tattoo itself. 

The doctor may ask the following medical history questions:

• Do you have a history of contact allergies?⁹
• Do you have any previous dermatoses? These can include eczema and psoriasis.⁹
• Do you have any previous infections, such as hepatitis and human immunodeficiency virus (HIV)?⁹

The doctor may also request more details regarding an individual’s symptoms, including the following:

• How much time has passed since you got tattooed and the formation of the lesions on/around the area that has been tattooed?⁹
• Does exposure to sunlight seem to aggravate or accelerate the development of the condition/lesion?⁹
• Have the lesions you describe happened when you have been tattooed previously?⁹

The doctor may also ask questions relating to the tattoo:

• Is this the first time you have been tattooed with this type of ink? (as different inks contain different ingredients, and only particular types of ink may trigger an allergic reaction in an individual).⁹
• Is this your first tattoo?⁹
• Can you get a sample of the ink used for your tattoo?⁹
• Was the tattoo artist a professional in this field? (inexperience may result in poor inks being used, which have unregulated substances that may cause an allergic reaction).⁹

Patch testing

Patch testing is a technique used to study allergic contact dermatitis and to test for allergic reactions on your skin.⁹ A small amount of the allergy-inducing substance is applied to a patch, which is then applied to your skin. Positive reactions to the substance can occur either immediately or can be delayed, and thus many individuals are instructed to wait for 48 hours before removing the patch. 

Patch testing is done with the ink that is supposed to have caused the reaction, but in many cases, the test is negative.⁹ On several occasions the culprit may not be a substance in the ink itself, but a metabolite (a product of metabolic actions) that is produced when the ink is broken down by the body,⁹ suggesting that patch testing is not the best approach to diagnosing tattoo ink allergy.⁹

Treatment options

Topical steroids

Topical steroids are used to treat tattoo ink allergy as a first-line treatment, and may help aid to alleviate local inflammation induced by tattoo ink allergy. However, they are usually used temporarily and the results are unsatisfactory.¹⁰

Topical steroids are a versatile treatment that can be used in the following forms:

• Creams
• Lotions
• Gels
• Mousses
• Solutions
• Ointments
• Tapes and bandages

Topical steroids range in strength from mild to very potent. 

Examples of topical corticosteroids are listed below:

• Mild:  hydrocortisone skin cream and clobetasone
• Strong: betamethasone and mometasone

Corticosteroids can be also used to treat allergic (or contact) dermatitis, which can be caused due to tattoo ink allergy. 

Photoallergic reactions can occur when a tattoo is applied using red or yellow ink and the tattoo is overexposed to sunlight, and these reactions can be treated with topical steroids.¹¹

Oral antihistamines

Antihistamines reduce the symptoms of allergic reactions and can be used in the following forms:

• Lotions
• Gels
• Eye drops
• Nasal sprays
• Liquids
• Syrups
• Tablets
• Capsules

Antihistamines are divided into two sub-groups: those that cause drowsiness, and those that do not. Those that cause drowsiness include chlorphenamine, whereas those that do not include loratadine.

Antihistamines work by blocking the effects of histamine. Histamine is a chemical that is released from some cells when the tattoo ink is recognised as being a foreign presence in the body by the immune system.¹² The immune system releases a type of antibody known as immunoglobulin E, which binds to mast cells, a type of immune cell, causing them to release histamine.¹² Increased histamine levels in the blood cause blood vessels to dilate, resulting in swelling, a main characteristic observed during an allergic reaction. Antihistamines aim to block the effects of histamine, and can therefore reduce effects such as swelling.

Tattoo ink removal

Whilst photoallergic reactions caused by yellow and red tattoo ink can be treated with topical corticosteroids, another line of treatment is tattoo ink removal. Tattoo ink removal is a process that can delay the potential allergic reaction induced by these ink pigments.¹¹ 

Removal of the allergen-causing pigment via laser removal has been shown as a promising treatment, especially for those who have had failed treatments with topical corticosteroids.¹⁰ CO₂ laser therapy has proven to be effective, with 33.3% of those using this treatment achieving full remission, and with only 16.7% of lesions showing no improvement after this therapy.¹⁰

Prevention

Several ways through which tattoo ink allergy can be prevented are listed below.

Researching a tattoo artist

Ensuring that a tattoo artist is reputable is important by checking their customer reviews. It is also important to know that they adhere to health and safety regulations to prevent tattoo ink allergy.

Consultation with a dermatologist

A dermatologist can diagnose conditions such as eczema and psoriasis, which can increase the likelihood of adverse reactions to tattoo ink. Dermatologists can also provide advice on what to avoid, and what to look for when getting a tattoo, when you are prone to dermatoses, therefore reducing the likelihood of tattoo ink allergy. For example, research has shown that eczema flare-ups are less common when black ink is used, and dermatologists usually advise waiting until eczema flare-ups have passed before tattooing.

Ink sensitivity testing

Patch testing can be used to determine whether there is an allergic reaction to an ink sample and to identify what the allergens are before tattooing.

Complications and long-term effects

Scarring

In most cases, if the infected area that is experiencing the allergic reaction is properly taken care of, typically through the treatment options mentioned in this article, there will be no scarring. However, untreated allergic reactions may cause tattoo disfigurement and scarring. 

Reccurrence

Reccurrence of a tattoo ink allergy may happen due to delayed hypersensitivity. This means that the allergic reaction’s symptoms may manifest days, months or even years after the individual has been tattooed.⁴ Recurrence may also happen if the tattoo is unprotected by SPF in direct and prolonged exposure to sunlight, resulting in phototoxic reactions.⁶

Impact on future tattoos

If you have a tattoo ink allergy and plan on getting another tattoo, an allergy patch test can be conducted to see which ingredients in the tattoo ink you are allergic to. These ingredients can be then avoided for future tattoos. Many may also decide not to get tattooed again if they have had an adverse allergic reaction.

Summary

Tattoo ink allergies occur in approximately 10% of those who decide to get tattooed and the ink colour that causes the most allergies is red. Tattoo ink allergies may occur immediately or may be delayed, occurring possibly years after the individual has been tattooed. Treatments include topical corticosteroids, oral antihistamines, and possibly tattoo ink removal. Making an informed decision about where to go for your tattoo is important to reduce the risks of tattoo ink allergy; going to a reputable artist who is knowledgeable about tattoo ink ingredients and has good knowledge of health and safety guidelines can help avoid the development of a tattoo ink allergy. Ensure that after the tattoo procedure is finished, correct aftercare will follow, by avoiding sunlight and using SPF where necessary, whereas avoiding scented lotions. If you have any dermatoses seek advice from a dermatologist before getting tattooed, as certain dermatoses such as eczema can be a risk factor for tattoo ink allergy.