Corticosteroids for Poison Ivy, Oak, or Sumac - Topic OverviewSee related handout on contact dermatitiswritten by the authors of this article. Contact dermatitis is a common inflammatory skin condition characterized by erythematous dsoe pruritic skin lesions that occur after contact with treatment poison ivy prednisone dose foreign substance. There are two forms of contact dermatitis: Irritant contact dermatitis is caused by the non—immune-modulated irritation of the skin by a substance, leading corticoides ejemplos skin changes. Allergic contact dermatitis is a delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin; skin changes occur after reexposure to the substance.
Diagnosis and Management of Contact Dermatitis - American Family Physician
See related handout on contact dermatitis , written by the authors of this article. Contact dermatitis is a common inflammatory skin condition characterized by erythematous and pruritic skin lesions that occur after contact with a foreign substance. There are two forms of contact dermatitis: Irritant contact dermatitis is caused by the non—immune-modulated irritation of the skin by a substance, leading to skin changes. Allergic contact dermatitis is a delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin; skin changes occur after reexposure to the substance.
The most common substances that cause contact dermatitis include poison ivy, nickel, and fragrances. Contact dermatitis usually leads to erythema and scaling with visible borders. Itching and discomfort may also occur. Acute cases may involve a dramatic flare with erythema, vesicles, and bullae; chronic cases may involve lichen with cracks and fissures.
When a possible causative substance is known, the first step in confirming the diagnosis is determining whether the problem resolves with avoidance of the substance. Localized acute allergic contact dermatitis lesions are successfully treated with mid- or high-potency topical steroids, such as triamcinolone 0. If allergic contact dermatitis involves an extensive area of skin greater than 20 percent , systemic steroid therapy is often required and offers relief within 12 to 24 hours.
In patients with severe rhus dermatitis, oral prednisone should be tapered over two to three weeks because rapid discontinuation of steroids can cause rebound dermatitis. If treatment fails and the diagnosis or specific allergen remains unknown, patch testing should be performed. Contact dermatitis is a common inflammatory skin condition characterized by erythematous and pruritic skin lesions after contact with a foreign substance.
The condition can be categorized as irritant or allergic. Irritant contact dermatitis is caused by non—immune-modulated irritation of the skin by a substance, leading to skin changes. In patients with contact dermatitis, the priority is to identify and avoid the causative substance.
On areas with thinner skin e. If allergic contact dermatitis involves extensive areas of the skin greater than 20 percent , systemic steroid therapy is often required and offers relief within 12 to 24 hours.
For information about the SORT evidence rating system, go to https: Occupational skin diseases rank second only to traumatic injuries as the most common types of occupational disease. Chemical irritants, such as solvents and cutting fluids used in machining, account for most cases of irritant contact dermatitis. One study showed that hands were primarily affected in 64 percent of workers with allergic contact dermatitis and 80 percent of those with the irritant form.
Irritant contact dermatitis is caused by skin injury, direct cytotoxic effects, or cutaneous inflammation from contact with an irritant. Symptoms may occur immediately and may persist if the irritant is unrecognized. Allergic contact dermatitis is caused by a type IV, T cell—mediated, delayed hypersensitivity reaction in which a foreign substance comes into contact with the skin and is linked to skin protein, forming an antigen complex that leads to sensitization.
Upon reexposure of the epidermis to the antigen, the sensitized T cells initiate an inflammatory cascade, causing the skin changes associated with allergic contact dermatitis. Common substances that cause contact dermatitis include poison ivy, nickel, and fragrances.
Nickel is a component of many different types of metals, including white gold, German silver, nickel and gold plating, solder, and stainless steel. Of the approximately 2, fragrance ingredients currently used in perfumes, at least are known contact allergens. Fragrance mix produces a patch testing reaction in about 10 percent of patients with eczema; 1. Neomycin is a common over-the-counter topical antibiotic.
Because of the antibacterial and antifungal properties of organomercurials, thimerosal has been used as a topical disinfectant and preservative in medical preparations. The clinical presentation of contact dermatitis varies based on the causative allergen or irritant and the affected area of skin.
Table 1 summarizes the features that help distinguish between irritant and allergic contact dermatitis. Information from reference 1. Contact dermatitis usually manifests as erythema and scaling with relatively well-demarcated, visible borders. The hands, face, and neck are usually involved, although any area can be affected.
Irritant contact dermatitis may occur on the lips with excessive lip licking and in the diaper region irritant diaper dermatitis. Some manifestations of contact dermatitis can be both allergic and irritant. The patient may describe itching and discomfort, but some patients seek medical care based on the appearance of the rash.
Patient history is crucial in making the diagnosis, and the causative substance must be determined to resolve the dermatitis and prevent further damage.
A common cause of allergic contact dermatitis is exposure to urushiol, a substance in the sap of rhus plants e. Rhus plants often brush across the skin causing linear streaks of erythema and vesicles Figure 1. Rhus dermatitis may also cover large areas of the body, including the face and genitals, leading to severe discomfort and distress.
More than 70 percent of persons who are exposed to urushiol can become sensitized. Allergic contact dermatitis caused by metals in jewelry often can be diagnosed with observation of the rash. Less expensive jewelry, and metal belt buckles and pant closures containing nickel commonly cause allergic contact dermatitis Figure 2.
Inexpensive kits that use dimethylglyoxime to test metals for nickel are widely available to consumers online. Common causes of allergic contact dermatitis from nickel exposure. Reaction to metal in A belly-button ring, B earring, C belt buckle, D pant closure. Note the scaling and erythema typical of this reaction. Allergic contact dermatitis from topical products e. Dermatitis of the hand has variable presentations, from mild irritant dermatitis to a more severe allergic contact dermatitis Figure 5.
Dermatitis of the foot is more common on the dorsal surfaces rather than on the soles Figure 6. Allergic contact dermatitis caused by neomycin A on the leg in the pattern of a large nonstick pad used to cover the antibiotic ointment and B under the eyes.
Acute allergic contact dermatitis caused by A topical herbal medicine for a sprained ankle severe reaction , B fragrance in deodorant, and C adhesive tape used after abdominal hysterectomy. Contact dermatitis of the hand. A Irritant contact dermatitis in a health care worker.
B Allergic contact dermatitis in a custodial engineer. Allergic contact dermatitis from new shoes. Note the typical distribution on the dorsum of the feet. The diagnosis of contact dermatitis is most often made with history and physical examination findings. Table 2 summarizes the differential diagnosis of contact dermatitis. More widespread than contact dermatitis and follows a certain distribution involving flexor surfaces. Occurs on the hands and feet with clear, deep-seated vesicles resembling tapioca; erythema; and scaling.
Usually occurs between toes, on the soles, and on the sides of the feet; whereas contact dermatitis is more common on the dorsum of the foot. Irritant and allergic contact dermatitis may be complicated by bacterial superinfection, and bacterial culture should be considered with the presence of exudate, weeping, and crusting. A potassium hydroxide KOH preparation is useful if tinea or Candida infection is suspected, because these fungal infections can have erythema and scaling similar to contact dermatitis.
If the KOH preparation has negative results but a fungal etiology is still suspected, a fungal culture should be sent for laboratory testing. Dermoscopy and microscopy can be used to look for scabies and mites. When a possible causative substance is known, the first step in confirming the diagnosis is observing whether the problem resolves with avoidance of the substance. If avoidance and empiric treatment do not resolve the dermatitis or the allergen remains unknown, patch testing may be indicated.
In one study, patch testing had a sensitivity and specificity of between 70 and 80 percent. Patch testing should not be confused with other types of allergy testing. Skin prick and radioallergosorbent tests are used for the diagnosis of type I hypersensitivity, such as respiratory, latex, and food allergies, but not for contact dermatitis. See Figure 7B for a photo of the panels with a positive reaction for No.
Adapted with permission from T. Accessed April 15, A Allergic contact dermatitis from a chemical in hair dye. B Patch testing in the same patient. See Table 3 for names of each allergen in the panels. If the suspected allergen is not included in the TRUE Test, the patient may be referred to a subspecialist who offers customized patch testing.
Personal products, such as cosmetics and lotions, can be diluted for specialized patch testing. However, because it is difficult to clinically distinguish between allergic and irritant contact dermatitis, these agents are often used successfully for the irritant form.
If the patient is comfortable after this initial therapy, the dose may be reduced by 50 percent for the next five to seven days. The rate of reduction of the steroid dosage depends on factors such as the severity and duration of allergic contact dermatitis, and how effectively the allergen can be avoided.
A steroid dose pack has insufficient dosing and duration and should not be prescribed. There is no evidence to support the use of long-acting injectable steroids in the treatment of contact dermatitis.
In patients with nickel-induced contact dermatitis, it is helpful to cover the metal tab of jeans with an iron-on patch most effective or a few coats of clear nail polish.
Clear nail polish can also be used on belt buckles, but may need to be reapplied often. Some patients may be allergic to preservatives used in the base of steroid creams. Steroid ointment is recommended because it allows the medication to maintain contact with the skin longer and there is little risk of an allergic reaction allergic reaction to the steroid itself is rare.
Also, soaking the affected areas before applying the steroid is thought to help improve penetration and increase its effectiveness. Although antihistamines are generally not effective for pruritus associated with allergic contact dermatitis, they are commonly used.
Sedation from more soporific antihistamines e. Already a member or subscriber? Address correspondence to Richard P.