What are the other Names for this Condition? (Also known as/Synonyms)

• Phototoxic Dermatitis due to Topical Applications
• Topical Phototoxic Reaction
• TPD (Topical Phototoxic Dermatitis)

What is Topical Phototoxic Dermatitis? (Definition/Background Information)

• Photosensitivity can be described as an allergic reaction of the body (or skin) on exposure to the sun (ultraviolet light). This immune reaction may also occur on the usage of certain drugs, medications, creams, or chemicals, with subsequent exposure to sunlight (or ultraviolet light). This condition is termed as drug/chemical induced photosensitivity. The condition can be phototoxic or photoallergic
• The signs and symptoms of phototoxic drug (or chemical) induced photosensitivity can be local (confined to an area of skin) or systemic (widespread in the body). Thus, not only the skin, but other body parts and organs can also be affected
• Topical Phototoxic Dermatitis (TPD) is caused by a variety of cosmetics, therapeutic drugs, or industrial chemicals, and the signs and symptoms are normally limited to the skin area of application/exposure
• It can result in burning/itching sensation, skin rashes, and formation of blisters. In some individuals, the skin lesions due to Topical Phototoxic Dermatitis can last for a long duration
• The primary treatment for Topical Phototoxic Dermatitis is discontinuation or stoppage of the offending ointment/drug/chemical. In a majority, the prognosis of the condition is typically excellent with suitable treatment

Who gets Topical Phototoxic Dermatitis? (Age and Sex Distribution)

• Topical Phototoxic Dermatitis is an uncommon condition caused by a variety of topical agents (that may be used for other underlying conditions, or when there is an unintentional contact with the chemical) with subsequent sun exposure. Any individual, of any age, may be at risk for the condition
• It can affect both males and females
• The condition occurs worldwide; individuals of all racial and ethnic background may be affected

What are the Risk Factors for Topical Phototoxic Dermatitis? (Predisposing Factors)

• The key risk factor for Topical Phototoxic Dermatitis is the use of certain drugs, applications, or the contact with certain chemicals that can cause the condition as a side effect
• There a variety of medications, drugs, and chemicals observed to induce this condition

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Topical Phototoxic Dermatitis? (Etiology)

Topical Phototoxic Dermatitis occurs as an adverse reaction of skin to certain applications, medications, or chemicals.

• The topical creams or lotions may be used for various conditions. A chemical exposure may also occur from an industrial or agricultural source. This is then followed by an exposure to ultraviolet light (either from the sun or from other sources)
• These drugs/chemicals cause the formation of free radicals, which when exposed to UV light causes the release of certain chemicals such as serotonin, prostaglandins, tumor necrosis factor alpha, and cytokines
• The offending drug/chemical potentially causes an abnormal cell-mediated immune response in the skin, resulting in the associated signs and symptoms of the condition. However, sometimes, the appearance of signs and symptoms due to the drug or chemical may not be observed immediately

Note: Both Topical Phototoxic Dermatitis and systemic phototoxic dermatitis are forms of phototoxic drug (or chemical) induced photosensitivity.

What are the Signs and Symptoms of Topical Phototoxic Dermatitis?

The signs and symptoms of Topical Phototoxic Dermatitis occur at the area of drug/chemical exposure (where creams and lotions are applied or due to an unintentional chemical contact) and following an interaction with UV light or sunlight.

• The condition is also termed ‘local’ and the signs and symptoms are mostly confined to the area of exposure
• It may have a slow onset. In some cases, the appearance of the signs and symptoms is not immediately observed following exposure to the drug or chemical; it may take weeks and months for them to develop

The signs and symptoms of Topical Phototoxic Dermatitis may include:

• Itching all over the body; burning sensation
• Fever
• Redness of skin
• Blister formation (vesicles and bullae)
• Hemorrhage can occur under the nails (subungual hemorrhage)

The severity of the condition may vary; it is difficult to predict who will get mild or severe symptoms.

How is Topical Phototoxic Dermatitis Diagnosed?

The following are the diagnostic methods and tests that may be used for Topical Phototoxic Dermatitis:

• A complete physical examination and a thorough medical and occupational history (which includes the use of any drugs, nature of occupation, etc.) are very important
• Dermoscopy: Dermoscopy is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination, who examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. A biopsy is performed to rule out other similar conditions

Note: In most cases, a diagnosis can be made by the dermatologist through a physical examination, signs and symptoms study, and medical history assessment, without resorting to a biopsy.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Topical Phototoxic Dermatitis?

The complications of Topical Phototoxic Dermatitis may include:

• Bacterial and fungal infections: The condition may cause continuous itching and scaling of the skin, which creates skin moistness, providing a suitable environment for bacteria and fungi to grow and thrive
• The skin heals with increased or decreased pigmentation
• In some individuals, the skin lesions can last for years resulting in self-image issues, emotional stress, and psychological trauma (depression)

How is Topical Phototoxic Dermatitis Treated?

The treatment of Topical Phototoxic Dermatitis may include:

• Discontinuing the topical ointment or cream responsible for the side effect may result in a cure
• In case the condition is due to an industrial or agriculture exposure to a certain chemical, then suitable protective measures may be taken to avoid contact with the offending chemical. This may also result in a cure
• Topical treatment includes cooling the skin using moist towels and moisturizing creams to soothe the condition
  • Use of topical ointments, lotions, and creams - these may be antiseptic and anti-inflammatory applications
  • Topical steroidal creams can help reduce inflammation
• Systemic treatment may be required in some cases
  • It may include medications, such as aspirin, non-steroidal anti-inflammatory drugs, and over-the-counter painkillers
  • In severe cases, oral steroids and IV fluids may be necessary
• Providing reassurance and helping with feelings of stress and anxiety
• Follow-up care with regular screening and checkups are important, since the condition may last for many months and years

A few self-care tips and home remedies that may prevent aggravation of the condition may include:

• Completely avoid scratching the affected areas
• A comfortable, cool bath may help soothe the skin; but, avoid excessive washing and scrubbing of the skin
• Wear smooth cotton clothes
• Use only mild perfumes, soaps, and detergents
• Drinking lots of water or fluids

How can Topical Phototoxic Dermatitis be Prevented?

Currently, it is not possible to prevent Topical Phototoxic Dermatitis.

• Stopping the topical application or cream causing the condition as early as possible is important. The healthcare provider may prescribe alternative medications to treat the existing, underlying condition
• If the allergic reaction is following an exposure to industrial compounds or chemicals, then suitable protective or safety gear may be used to prevent any further contact with the chemical
• Periodic monitoring or follow-up of the condition with the healthcare provider is recommended

What is the Prognosis of Topical Phototoxic Dermatitis? (Outcomes/Resolutions)

• The prognosis of Topical Phototoxic Dermatitis is excellent with appropriate treatment, in most cases
• In general, it is easier to treat topical or localized conditions than systemic or widespread conditions

Additional and Relevant Useful Information for Topical Phototoxic Dermatitis:

Cleaning the skin too hard with strong chemicals or soaps may aggravate the skin condition. Care must be taken avoid strong soaps and chemicals that can potentially worsen the condition.